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Episode Notes

Source / episode info

  • Episode: 317
  • Title: Divine Intervention Episode 317 – Breastfeeding, Newborn Jaundice, and The NBM Es.
  • Published: 2021-06-01
  • Source: Episode page

One-liner

This episode provides a comprehensive review of breastfeeding benefits (for both mother and child), common breast pathologies (mastitis vs. abscess), the pathophysiology and management of neonatal jaundice, and appropriate formula selection based on pediatric GI status.

High-yield summary

  • Breastfeeding Benefits: Decreases risk of infections (meningitis, pneumonia), autoimmune diseases (Celiac disease), and certain cancers (ovarian/breast) due to immune factors like IgA and lactoferrin in breast milk.
  • Neonatal Jaundice Classification: Any direct (conjugated) bilirubin is always pathologic. Physiologic jaundice is indirect (unconjugated). Pathologic causes include biliary atresia or cholestasis.
  • Breast Pathology Differentiation: Mastitis presents as unilateral tenderness/redness, while a suspected breast abscess involves a palpable, fluctuating mass. Both require supportive care; abscess often requires Incision and Drainage (I&D).
  • Jaundice Management Thresholds: Phototherapy is indicated for unconjugated hyperbilirubinemia. Partial exchange transfusion is required if total bilirubin > 25 mg/dL or if the level continues to rise despite phototherapy.
  • Formula Selection Rules: Use soy protein formula for galactosemia; protein hydrolysate formula for severe food allergies (cow/soy); amino acid-based formula for short gut syndrome/extensive bowel resection.

Learning objectives

  • Differentiate between various types of neonatal jaundice (physiologic vs. pathologic) and their underlying pathophysiology.
  • Identify specific contraindications to breastfeeding in both mother and child.
  • Select appropriate specialized formulas based on the patient's gastrointestinal status or metabolic disorder.
  • Distinguish clinical presentations, management, and risk factors for common postpartum breast infections (mastitis vs. abscess).
  • Understand the physiological mechanisms behind bilirubin metabolism and jaundice treatment (phototherapy/exchange transfusion).

Board exam buzzwords

ConditionKey FindingAssociationBoard Exam Tip
ColostrumHigh IgA levelsFirst milk produced post-partumRemember that colostrum is rich in immune factors, making it highly protective.
Breast AbscessFluctuating mass; Unilateral tendernessIncision and Drainage (I&D)Do not delay drainage for simple antibiotics if fluctuation is present.
Pathologic JaundiceDirect bilirubin > 1-2 mg/dL OR onset < 24 hoursCholestasis, Biliary AtresiaAlways suspect a structural or metabolic problem when direct bilirubin is elevated.
GalactosemiaPositive reducing substances in urine; CataractsDeficiency of galactonolactone transferaseRequires immediate switch to soy protein formula (lactose/galactose source).

Rapid review table

TopicKey PointContextExam Relevance
Breastfeeding JaundiceIncreased enterohepatic recirculation of unconjugated bilirubin.Dehydration or inadequate intake in the first week of life.Treatment is adequate feeding, not phototherapy.
Pathologic JaundiceDirect (conjugated) hyperbilirubinemia.Cholestasis, biliary atresia, sepsis.Always requires investigation; never assume it's physiologic.
Breast Abscess vs MastitisFluctuating mass is key for abscess.Unilateral pain/fever postpartum.Management of abscess often involves drainage rather than just antibiotics.
Formula SelectionAmino acid-based formula.Short gut syndrome, extensive bowel resection.Used when the GI tract cannot process intact proteins due to malabsorption.

Board-speak -> diagnosis

Board-speak / Vignette phraseDiagnosis / ConceptWhy it fits
A postpartum woman presents with unilateral breast tenderness, fever, and a palpable, fluctuating mass in the breast.Breast Abscess (Suspected)The combination of fluctuation + localized symptoms strongly suggests an abscess requiring drainage, differentiating it from simple mastitis.
A neonate is found to have jaundice within the first 24 hours of life.Pathologic JaundiceAny onset of jaundice in the first day of life is considered pathological and requires immediate investigation (e.g., hemolysis, biliary atresia).
A child with severe protein malabsorption due to extensive bowel resection presents for nutritional counseling.Amino Acid-Based FormulaThe gut cannot process intact proteins; amino acids are the simplest nitrogen source required for nutrition in this state.
A neonate is exclusively breastfed and has jaundice, particularly during the first week of life.Breastfeeding JaundiceCaused by inadequate intake leading to dehydration and increased enterohepatic recirculation of unconjugated bilirubin. Management is adequate feeding.
A woman who plans to become pregnant while breastfeeding should be aware that prolonged lactation suppresses FSH/LH via prolactin.Prolactin Suppression of HPG AxisHigh levels of prolactin inhibit GnRH release, leading to decreased ovarian function and potential amenorrhea.
A child on a specialized formula due to severe cow's milk protein allergy is being managed in the NICU.Protein Hydrolysate FormulaThis formula breaks down proteins into smaller peptides, minimizing the immune response while providing necessary nutrition for allergies.

Differential diagnosis / distinguishing features

Types of Jaundice

Key FeaturesDistinguishing FindingsNext Step
Physiologic JaundiceIndirect bilirubin only; onset 2-4 weeks; mild.Observation and adequate feeding/hydration.
Breastfeeding JaundiceIndirect bilirubin only; first week of life; associated with poor intake.Ensure frequent, effective breastfeeding to prevent dehydration.
Pathologic JaundiceDirect bilirubin elevated OR onset < 24 hours.Urgent workup (e.g., direct Coombs test, liver function panel) to rule out biliary atresia/hemolysis.

Formula Selection

Key FeaturesDistinguishing FindingsNext Step
GalactosemiaPositive reducing substances in urine; cataracts.Soy protein formula (avoids galactose).
Severe Food AllergySymptoms of GI distress due to milk proteins.Protein hydrolysate formula (smaller peptides).
Short Gut SyndromeMalabsorption/steatorrhea after bowel resection.Amino acid-based formula (simplest nitrogen source).

Management pearls

  • Breast Abscess Management: The primary treatment is physical drainage ( I&D ) rather than solely antibiotics, especially on board exams.
  • Phototherapy Mechanism: Phototherapy works by converting water-insoluble unconjugated bilirubin to a more water-soluble form (lumirubin), facilitating excretion.
  • Bilirubinemia Management Escalation: If total bilirubin is > 25 mg/dL OR if the level continues to rise despite phototherapy, partial exchange transfusion is mandatory.
  • Vitamin Supplementation: Exclusively breastfed infants require supplementation with Vitamin K and Vitamin D.

Don't miss

🚨
Colostrum vs. Mature Milk: Colostrum (first milk) has significantly higher levels of immune factors like IgA compared to subsequent colostrum/mature milk.
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Pathologic Jaundice Rule: Never assume jaundice is physiologic if the direct bilirubin fraction is elevated, or if onset occurs within the first 24 hours of life.
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Contraindications Checklist: Key contraindications to breastfeeding include active TB, chemotherapy, HIV, and galactosemia.

Integration & clinical reasoning

  • Endocrine/Reproductive Integration (Prolactin): High levels of prolactin suppress the Hypothalamic-Pituitary-Gonadal (HPG) axis by inhibiting GnRH release, leading to decreased FSH/LH secretion. This mechanism is key for understanding lactation's impact on reproductive hormones.
  • GI/Metabolic Integration (Bilirubin): Dehydration and poor intake lead to increased enterohepatic recirculation of unconjugated bilirubin, exacerbating jaundice in the first week of life (Breastfeeding Jaundice).
  • Nutritional/Pediatric Integration: The choice of formula must match the degree of GI damage. Amino acid formulas are reserved for severe malabsorption (short gut), while hydrolysates address specific protein sensitivities.

Concept connections / cross-references

  • For detailed information on endocrine axes and hormonal suppression, see [ Episode 12 ].
  • For general pediatric care guidelines and screening protocols, review resources from [ Episode 45 ].

High-yield association table

ConditionAssociationMechanismClinical Significance
Breast AbscessFluctuating mass; Unilateral symptoms.Localized infection requiring physical drainage.Differentiates it from simple mastitis and guides management toward I&D.
Pathologic JaundiceDirect hyperbilirubinemia OR onset < 24 hours.Cholestasis, biliary atresia, hemolysis.Requires immediate workup; never assume physiologic origin.
Breastfeeding JaundiceDehydration/Poor intake in first week of life.Increased enterohepatic recirculation of unconjugated bilirubin.Management is improving feeding frequency and adequacy.
GalactosemiaDeficiency of galactonolactone transferase.Inability to metabolize galactose into glucose.Requires strict avoidance of lactose-containing formulas/milk sources.

Key terms glossary

TermDefinitionContextExample
ColostrumThe first milk produced post-partum.Breastfeeding benefits; immune factors.Contains high levels of IgA, providing immediate passive immunity to the neonate.
Enterohepatic RecirculationReabsorption of bile acids/bilirubin from the gut back into circulation.Jaundice pathophysiology (Breastfeeding jaundice).Increased recirculation increases the amount of unconjugated bilirubin available for re-excretion.
Protein HydrolysateFormula where proteins are broken down into small peptides.Severe food allergies (e.g., cow/soy milk allergy).Used when intact protein absorption is compromised due to immune reaction.
Unconjugated BilirubinIndirect bilirubin; water-insoluble form.Neonatal jaundice; phototherapy target.This fraction accumulates in the blood and requires conversion for excretion.

Study optimization

TopicStudy ApproachPriorityResources
Neonatal JaundiceMaster the pathophysiology of bilirubin metabolism (unconjugated vs conjugated).HighReview algorithms for jaundice workup; memorize thresholds (24 hours, 25 mg/dL).
Breastfeeding CareCreate a checklist of benefits and contraindications.Medium-HighFocus on why certain things are contraindicated (e.g., chemo destroys rapidly dividing cells).
Pediatric NutritionUse flowcharts to match GI status to formula type.HighPractice vignettes requiring selection: Galactosemia -> Soy; Short Gut -> Amino Acid.

Question pattern recognition

  • Pattern: Jaundice onset within the first 24 hours of life -> Pathologic jaundice (Think hemolysis or biliary atresia).
  • Pattern: Unilateral breast tenderness + fluctuating mass in a postpartum woman -> Breast Abscess (Requires I&D).
  • Pattern: Neonate with unconjugated hyperbilirubinemia and poor feeding/dehydration in the first week of life -> Breastfeeding Jaundice (Management: Improve intake).

Test yourself

Common mistakes to avoid

🚫
Mistake: Assuming all jaundice is physiologic if the direct bilirubin fraction is normal. (Correction: Always check onset and look for other signs of cholestasis.)
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Mistake: Treating a suspected breast abscess with antibiotics alone. (Correction: Fluctuating mass requires I&D first, even if infection is present.)
🚫
Mistake: Giving phototherapy for direct hyperbilirubinemia. (Correction: Phototherapy only works on unconjugated bilirubin; it does not treat conjugated jaundice.)

Common traps

⚠️
Trap 1 (Jaundice): Assuming that the most common cause of neonatal jaundice (physiologic) is always benign, even if there are signs of cholestasis or early onset. (Remember: Direct bilirubin elevation is a red flag).
⚠️
Trap 2 (Breastfeeding): Believing that breastfeeding is contraindicated in all postpartum infections. (Correction: Mastitis/abscess management should encourage continued breastfeeding unless medically necessary to stop.)
⚠️
Trap 3 (Formula): Selecting a general allergy formula (hydrolysate) when the underlying cause is a specific metabolic deficiency (galactosemia). (Remember: Specific diagnosis dictates specific avoidance, e.g., soy for galactosemia).

Original transcript with highlights

Original transcript with highlights

Okay, welcome. My name is Divine. This is a episode 317 of the Divine Intervention Podcasts and this is going to be a pediatric themed podcast but I'm going to call this newborn jaundice, breastfeeding and the NBM exams. These are two topics that are very high yield and for some bizarre reason people just tend to scrub a lot on these topics. So I want to have a podcast where I re-brick it down and hopefully you find this to be helpful. And for those that are studying for Step 2 CK Step 3, I have a course that's coming up in the month of June. It gave this month, right? So like on the 17th of this month I have the NBM test taking strategy course. It's from 3 to 5 30 pm Pacific Standard Time and then I have the comprehensive 20-hour step 2 CK Step 3 course. It's going to be on the 18th and 19th, so on a Friday and a Saturday. It's going to be 10 hours each day. We're going to take two hour breaks, like two hour breaks during the course of the day. And then at the end of the month on the 20th of June I have the NBM test taking strategy course from 2 to 4 30 pm Pacific Standard Time and then the 20-hour course as well. I have them from the 29th of June to the 2nd of July. It's going to be five hours each day from 11 pm to 4 pm Pacific Standard Time. So if you're interested in any of those courses just shoot me an email and I'll be more than happy to give you some more information while there's still spots left. Okay, so let's jump right into it.

So let's maybe start with breastfeeding first. I think that's probably like a good starting point. So we know that breast milk right is something that really comes in and I'm going to be essentially talking about just multiple different variants, right? That the NBM can pose with breastfeeding. So the first thing I guess I want to talk about is how long are you supposed to breastfeed a child for? Right? You want to exclusively breastfeed a child for at least six months on NBM exams, right? Obviously longer than that is better, right? But you want to breastfeed a child for at least six months on an NBM exam, right? And one of the reasons that women don't breastfeed, I mean the women don't make breast milk while you're pregnant right? It's because of progesterone. Progesterone suppresses a prolactin's effect, right? So you're not able to get breast milk during, you know, during pregnancy, right? But the moment the child is born, the source of progesterone is gone, aka the placenta. So now you can start making a ton of breast milk. So usually within like two to five days, the breast milk will, the breast milk will coming. Now on NBM exams, what if you get a question and they say, oh, give you some, you know, be like a question about like a woman breastfeeding a child and then they say which of the following is an associated benefit of this practice or breastfeeding or whatever, right? So what are some things you get from breastfeeding a child?

Well, it decreases your risk for certain high-ealth things. So one is like sorting if undef syndrome, seeds, and actually it does decrease your risk. And then many of these allergic diseases, right? Like eczema, asthma, things of that nature. That risk is also decreased significantly by breastfeeding. And also your immune system just works better as a child when you're breastfed by mom because again, remember you're getting that IGE from mom's breast milk. And then in addition to that, your immune system is just built up. There are all these immune factors like lactoferin and things like that that are already from breast milk that again really helped the baby. And then probably one of the highest yield things to know with the positive benefits of breastfeeding is that it actually decreases the risk of infections in the baby. Like really pretty much every infection. Menenditis, otitis media, pneumonia, sinusitis, necrotizing, and terror colliders, botulism, all those things your risk is decreased precipitously if you breastfeed the child. And then also just the development of autoimmune disease later in life, right? You actually, or even in childhood, you actually decrease that risk as well by breastfeeding, right? So things like celiac disease, for example, you can significantly decrease the risk of celiac disease in a child by breastfeeding. So those are all positive benefits associated with breastfeeding on end-beam exams.

But the good thing about breastfeeding is it's not just good for baby, it's also great for mom. So what are some of the positive benefits you could see on end-beam exams with regards to breast mom that is breastfeeding? Well, we know that first thing is first, it's going to help with weak loss, right? Because again, you're giving up some calories in that in that matter. And by losing weights, right? You're reducing the risk of the woman having like, because remember, that very part on period is a very dangerous period for getting stuff like M Is, P Is, DV Ds. So you can minimize that risk by the weak loss that is provided through breastfeeding, right? So it actually lowers the risk of, because you see some women after they deliver a child, right? You know, they're still really obese, which is no fault of theirs. They're still really obese. And then they go on to develop diabetes, right? So that risk of post-gestational diabetes melodies is decreased by breastfeeding the child. And again, just cardiovascular disease in general, the risk is decreased by breastfeeding the child. And then remember, if you breastfeed a child for a long period of time, it's almost like we're exposing yourself to prolactin for a long period of time. I'll say it again, if you breastfeed a child for a long period of time, you're literally exposing yourself to prolactin for a long period of time. Well, we know what prolactin does. Prolactin suppresses the HPG axis, right?

Prolactin directly inhibits the secretion of GNI, so if you're making less GNI than you're making less FSH and LH. And then you are basically going to be ovulating less. And if you're ovulating less, the thing that's going to happen is because remember for a woman every month, her ovary is literally explode. She secrets an egg, repairs that epithelium again. Next month, visual ovary is explode. Secrets an egg, you repair that epithelial lining again. So if that epithelial lining is not destroyed all the time because you're ovulating less, because you have high levels of prolactin, which is suppressing your HPG axis. You're actually going to decrease that person's risk of ovarian cancer. And then your breast cancer risk is also decreased a longer your breastfeed. Because again, if you think about it, just again, like I said, prolactin suppresses GNI reach. And if you suppress GNI reach, right? Your FSH and LH is going to go down. Your estrogen and purchasing is going to go down. Because remember, there are certain breast cancers that are ERPR positive, right? Certain breast cancers are ERPR positive. So if your breastfeed, you're making less because of the hyper-prolactinemia you're getting, you have less estrogen and purchasing. So you have less of a driving force for breast cancer. And then it's also very high yield to know that when a breastfeed, right? Again, it just has many good benefits in general.

If I'm not mistaken, I think I read a study back in the data says that if I'm on breastfeed, she's literally like burning like 500 calories every day. Just from breastfeeding. Don't quote me on that, but I'm pretty sure I read that like maybe like a few months or a few years, actually I've probably most of like a few years ago, right? So if you're burning 500 calories every day from breastfeeding and then think about it in seven days, you're burning 3500 calories. So that means in seven days, you're burning a pound. You're literally losing a pound a week, right? You know, all other factors being, you know, I would imagine being health constant, right? So breastfeeding has lots of benefits. I know like many developing countries are breastfeeding is like a big, big, big, big thing, right? It's done for some times up to three years old, right? Again, there's lots of benefits for that. But I know the more advanced countries, you know, they do breastfeeding for like six months and then they're like, I'm done, right? So again, I'd encourage you to kind of keep those things at the back of your mind. As you're studying for MbNXM, breastfeeding is a big high yield concept. And it's just kind of a simple concept, but they're just these little details that you kind of need to know on exams. And again, remember, breast milk right contains IGA, right? Breast milk contains IGA. That's a high yield thing to give out the back of your mind.

And the first breast milk you produce tends to have like higher IGA levels and higher immune marker levels than other breast milk you'll produce down the line, right? That's something that's called colostrum, C-O-L-O-S-T-R-U-M. Now, what if they give you a question about a patient and they tell you that we have the one that is three days post partum and she has like unilateral breast tenderness and she has a temperature of 102 and she's like 30 something years old. If you see that, I hope you're saying, oh, define this is mastitis, right? This is mastitis. Remember, mastitis, the most common cause of mastitis is staphoreus on MbNXM. And we're going to treat you with dikeloxacillin or oxacillin. Remember, those are those anti-staphilococopinicillins. So you use dikeloxacillin or oxacillin and you're going to tell the one to keep breastfeeding so that she can clear the bug, right? You're not doing anything evil to be by breastfeeding him even if you have a mastitis. Now, what if they give you a question about a woman? So notice for mastitis, I said it's unilateral breast tenderness. So what if they give you a question about a woman that has unilateral breast tenderness? She's two days post partum, she's 34 years old and she has a temperature of 102. And then, they tell you that you can pop it, fluctuate mass in the breast, right? Again, this is unilateral. If you see this, I hope you're saying, oh, divine, this is potentially some kind of breast abscess, right?

Whenever you see that fluctuation mass, you see the fever and stuff, you're again, you're a lateral process, once you think about a breast abscess. So how do we manage breast abscesses on an immune exam? We're going to manage it by performing an incision and drainage. Usually on an immune exam, you don't need to do any kind of antibiotic therapy for breast abscess. And it's very high you to know they can say, oh, which of the following is the biggest? Which of the following is the biggest risk factor for a person having mastitis or a breast abscess? On an immune exams, the thing I want you to think about is, I want you to think of that person potentially having this think of the person potentially having this situation where, you know, because the newborn is trying to breastfeed, they cause these like micro-bricks in the breast, right? So in the areola. And then through that, you can then have bugs like stuff, or you're like skin floor, making it to the breast tissue and causing those problems. So that's kind of like the risk factor. Just again, from these micro-bricks in the skin, in the areola things, things like that. Okay, now what if they give you a question about a patient and they tell you that this patient has, you know, she's four days postpartum, she has bilateral breast tenderness. So notice this is not you, this is bilateral, this is bilateral. By lateral breast tenderness, she has a temperature of one or two, so she has a high fever, right?

And again, she's a 33-year-old female and you know, she's like four days postpartum. If you see this, I want you to think about breast engeorgement. That's the thing, the fact that it's out, because I mean, I hope that you're producing milk from like both breasts, right? So the fact that it's a bilateral process and this fever should tell you that you're dealing with breast engeorgement, right? So again, remember breast engeorgement bilateral process, mastitis and breast abscess, unilateral process. And then if a baby is exclusively being breastfed, right? What are some kinds of vitamins that should be, what should you try to supplement those kids with? Well, you want to make sure that those kids get vitamins K and vitamin D, right? In fact, it's easy to remember this if your Brooklyn Nets fan is Kevin Burant, KD, right? So vitamin K and vitamin D should be supplemented in kids that are exclusively brain breastfed. I mean, before you leave, before a baby leaves the hospital, they're going to get an eye-em-short of vitamin K. And then you know, you want to make sure that you supplement vitamin D, because those things are very low in breast milk. Now, what are some contraindications to breastfeeding on end-beam exams? So what are some situations where you'd see, and you'd be like, okay, so we can't really breastfeed this child?

Well, some of those high-yield contraindications to keep in mind is if a mom is on chemotherapy, for example, if mom is on chemo, you absolutely, absolutely should not breastfeed that child on an end-beam exam, because again, remember chemotherapy destroys rapidly dividing cells. So if you're given a baby is literally like a big hub of rapidly dividing cells, right? So you don't want to give chemo to baby, right? So that's probably not a smart idea. If a woman has active breast cancer, you also don't want to be breastfeeding the baby, right? And then if a woman is like abuse these drugs, right? You also don't want to breastfeed the baby. If a woman has like active TB, active TB is an absolute contraindication to breastfeeding on end-beam exams. If you have like active herpes lesions on the breast, in those circumstances, you also do not want to breastfeed the baby on an end-beam exam, right? And then also having HIV. Remember the exam for those of you that are listening to this podcast, you know, for the most of our thing to do in the US MLA exams, right? So in general, like in the US, if a woman has HIV, she's not going to be breastfeeding that baby, so that you don't transmit it to the feeders, right? And then galactosemia, right? It is another very high level. Remember galactosemia is a deficiency of an enzyme called galactos one phosphate, urinal transfer. So you're not able to take galactos down the pathway to all the way to glucose, right?

You remember usually these kids, they will have like positive reducing substances in your urine and they will have like a pardospelino megaly and many times they can also have cataracts on an end-beam exam. So again, very high up to keep that at the back of your mind for tests. And then how do you, let's say, you know, I think one thing that the end-beam like really likes to focus on these days is they'll give you like a select set of conditions and ask you what kind of baby formula should you give these kids? Well, so let's maybe start with, let's maybe run through a few vignettes, right? So what if we see a child that has this galactosemia, right? This essential galactosemia I just talked about. Or let's say it's a child that, you know, has like lactose intolerance. What kind of formula do you want to give those kids? What kind of formula do you want to give those kids? Well, now hope you're saying, oh, divine, I'm going to give that child a baby formula that's reaching like soy protein, right? These soy protein formulas actually pretty good in those, in those circumstances. And then what if they give you a question about a child and they tell you that this child has like just tons and tons and tons of food allergies, right? And you need to put that child on formula, right?

If you see something like this, especially if a child has like a cow milk allergy or a soy milk allergy, the key thing you want to keep at the back of your mind is you want to give that child formula that is reaching something called protein hydrolycate. It's very high up to another hydrolycate spelled as H-Y-D-R-O-L-Y-S-A-T-E, right? So you want to give formula that is rich in protein hydrolycate. Now, what if they give you a question about a child and they tell you that, oh, this child has had is like a child that was born prematurely, this child has had like extensive bowel resection because the child's birth was complicated by necrotizing intercalitis. What kind of formula would you want to give that child? I hope you're saying, oh, divine, I'm going to give this child an amino acid based formula, right? You want to give that child an amino acid based formula, right? Again, when a child has like shot got syndrome because you've caught out a ton of their bowel, those kids, they're going to have problems digesting proteins, right? So you want to give them like an amino acid based formula, an amino acid based formula. And then, you know, the best kind of formula to give a child, obviously breastfeeding is the best, but if for some reason you cannot breastfeed a child, then the thing you're going to do on an end-beaming exam, in general is you want to, you know, use like a cow's milk based formula, right?

You want to use like a cow's milk based formula just just in general on end-beamings. And then, should you give cow's milk to a like a newborn on end-beamings? I hope you're saying, divine, no, we're not going to do that, right? So remember, cow's milk in general is essentially contraindicated on end-beam exams. I'm not saying cow's milk from them, saying like just straight up cow's milk, right? It's contraindicated on end-beam exams in kids that are less than a year old. Remember, that scene rule also applies to like honey, right? So that you don't give those kids a botulism, right? So cow's milk, remember cow's milk is very low in iron, cow's milk is very low in fatty acids, right? So it's not necessarily the best thing for for kids on exams. And then what if they give you a question about a child and they tell you that, oh, this child was born on a farm, right? Or lives in a rural area. And then this child, you know, has like this constant fatigue is always sleepy, doesn't seem to participate, but we doesn't seem to be bonding with more much, right? And then they give you labs and you notice that the child's MCB is like 110 and then you notice that the hemoglobin is low. If you see this, I would really hope you're telling me that, oh, divine, this child has a full-eat deficiency, right? This child has a full-eat deficiency. So what's causing this child's full-eat deficiency? Well, the child's full-eat deficiency is being caused because the child is using good milk, right?

It's using good smell. Good smell is not the best smell, right? But again, they'll give you something about like, oh, they live on a farm and there's cows and goats on said farm, right? And they're feeding the child a ton of good smell. Good smell is really low in full-eat. So it can cause a megaloblastic anemia. It can cause a megaloblastic anemia on Mbim Exam. So that's something you want to kind of keep at the back of your mind as you study for these tests. Good smell is also low in iron, right? So again, it's like a double-warm in there, but the big thing you want to keep in mind with good smell on Mbim Exam is that it's low in full-eat. So it can cause a megaloblastic, it can cause a megaloblastic anemia, right? It can cause a megaloblastic anemia. And then some other things I guess I want to say, right? So what if they give you a question about a child, right, that has, you know, John this. So this is me still talking about breastfeeding, right? So they talk about this child and this child, you know, the tale of this child feeds like once every is a newborn, literally a neonate, feeds like and this is like two, three days after birth has like generalized yellow enough his skin. And then they tell you that this newborn latches on an tick's breast milk like every four or six hours or something like that and only ticks a small amount.

And then they're trying to get you to make the diagnosis and let's say they give you like the billiardubin and notice that the total billiardubin is like four or five and then the direct fraction of it is zero point five, right? So this child has an indirect type of anemia and you're noticing is at least and seven days of life. And then you also notice that this child is not being breastfed often, right? As a newborn, you're supposed to be getting breast milk like roughly every two hours. If you're getting it like four to six hours and you get a small amount each time, if you see this cluster of symptoms I just described, I really want you to think about breastfeeding jaundice until you think about breastfeeding jaundice, right? So one thing about breastfeeding jaundice remember the F in breastfeeding for the F in the first week of life, right? So what's the pathophys behind that breastfeeding jaundice? Essentially the thing that happens is the baby is not getting adequate amounts of breast milk, right? So because the baby is not getting adequate amounts of breast milk, the child is pretty much dehydrated. And when you are dehydrated that actually increases your GI transit time. So if you increase your GI transit time, you're going to have a lot of this process called entero hepatic recirculation.

Basically, entero hepatic recirculation is just something that happens where the billiardubin that you put in your GI tract instead of pooping it out, you know, has like stroke a bit, you know, converting it first to stroke a bit of linojene and then to stroke a bit of linojene and then pooping it out, right? You'll reabsorb more of it back into the circulation. So because the GI transit time is increasing, a child that is dehydrated, you're going to have more entero hepatic recirculation, you're going to reabsorb more billiardubin. And remember kids, they are not very good at handling billiardubin, right? Because they have very low levels of UDP, look around the cell transfer. I mean like as a newborn, your UDPGT activity levels is like 0.1 to like 1% of like adult activity levels. So in those circumstances, right, this child will be getting more billiardubin than they can handle. And remember kids, let me be let me backtrack a little bit here, maybe like divide away, we kids have a ton of billiardubin to you don't start with. Well, remember as a child in utero, you're pretty much not using your lungs, right? Your lungs are literally like a bag of fluid. So because you're not using your lungs, being in utero is a state of relative hypoxia. So that state of relative hypoxia tells those cells in the kidneys, your paritabular cells in the kidneys and they make a ton of ipo, ton of very thropo eaten.

If you make a ton of very thropo eaten, well surprise surprise, the thing that's going to happen is you're going to have a very high hemoglobin, very high hematic rate. So kids after they are born, they're like, okay, my lungs work now. So let's maybe go ahead and dump down on this hemoglobin loop that we have, right? So as new, in the first few weeks of like, there's a lot of destruction of red blood cells. Remember as red blood cells are destroyed, that he is converted by billiardium reductase to, I mean by hemoxygenase first to biliverde and then biliverde reductase converts that, uh, biliverde into indribelyrobin, right? So kids, they're producing a ton of indribelyrobin. But then the enzyme to metabolize that indribelyrobin, to dribelyrobin does not exist, right? Or at least does not exist in adult quantities. So that's why kids are pretty supposed to have an jaundice, right? So that's why, essentially for childish dehydration because the child is not being breastfed regularly. Again, you're going to have increased entero hepatic recirculation. And if that happens, right? Again, the baby is going to have jaundice, right? This is what's called breastfeeding jaundice. And again, your treatment basically is just to make sure that the child is being fed adequately. And then what if they give you a presentation like, let's say like, second week of life going forward, right? Usually it's going to be within like eight to 14 days.

On an in-beaming example, though, you know, the kamikis six to 14 days, you know, just to blur their lines a little to mess with your head. But they give you a question about a child and this child, you know, they tell you that this child, physical exam is completely normal. This child is beginning with appropriately and everything, right? But you notice that this child has jaundice, right? Then I really want you to think about like something called breast milk jaundice, right? So the thing is the exact pathophysiology behind breast milk jaundice, no one really knows, but it's going to be like a really, really, really mild jaundice. And basically, people think that the pathophys involves a child having something, like some stuff in the breast milk that the child is consuming inhibiting UDP, look for a cell transfer, so if you inhibited UDP GT, obviously you're not going to be able to convert in drabili ribbon to drabili ribbon, but for the most part, the child is going to be fine. To be honest with you, they almost never on in-beaming exams test breast milk jaundice. I just decided to include it here for completeness sake. So I'll encourage you, in general, breast milk jaundice is very rarely the right answer ever on in-beaming exams because the presentation is very non-specific, but breastfeeding jaundice, the presentation is pretty specific, right? The presentation is pretty specific.

And then one thing I want to mention is, hopefully you know what qualifies as physiologic jaundice, right? Or maybe let's talk about qualifies as pathologic jaundice. Whenever a child has direct type of ulyrbini, literally for any reason, that's always going to be pathologic, right? Physiologic jaundice is indirect, right? So if you see a child and this child has direct type of ulyrbini, then I want you to think of pathological jaundice, right? And remember, the most common causes of pathological jaundice, right? On in-beaming exams, the first one we want to think about is biliria trisia. And then a second one we want to think about is a colidocosis, but if you see both pig biliria trisia, remember biliria trisia, you need to fix it as quickly as possible after birth, right? Within like the first two to four weeks of birth, right? Earlier is better with the cacipersidia, right? If not, the child is going to need a liver transplant. And then if you also have jaundice within the first 24 hours of life, that's also always pathological, right? A child should never develop jaundice within the first 24 hours of life if they do, and that's an example of pathological jaundice on in-beaming exams. Now if a child has like really bad jaundice, what are you going to do? Well, you're actually going to use phototherapy, right? For these kids. And what exactly does phototherapy do?

Because sometimes, instead of asking you about like phototherapy, they can ask you about the mechanism behind phototherapy actually helping. Well, the reason that phototherapy works is that it basically converts transbilirubin, which is water insoluble to cisbilirubin, which is water soluble, right? So that's why phototherapy with those belly lights are really helpful. Usually when you're doing phototherapy, you want to make sure you cover the child's eyes, because again, you don't want that light damaging the child's eye. Overwhelming the child's eye, visual apparatus. And then there are some situations where you want to go ahead and proceed to partial exchange transfusion on an in-beaming exam. Well, the situations where you're going to do that are things like, if for example, you've tried phototherapy with belly lights and it's not working, right? If phototherapy with belly lights is not working, then you need to notice that, wow, okay, this child's belly rebeaming is still rising, despite the use of phototherapy, then that's an indication for partial exchange transfusion. And then also, if a child has a total bilirubin that is more than 25, that's also an indication for partial exchange transfusion. The reason you want to get aggressive with treating John this in kids is that it can cause connectors, right?

So, usually it will be a question where like a few weeks after birth or a few months after birth, the child is somaland, the child is always lethargic, doesn't seem to be developing appropriately, has hearing problems, right? Because essentially that indirect bilirubin has crossed the blood brain barrier and it has deposited in the in the bizzle ganglia and then it has essentially damaged the child's brain, right? So, that's why you kind of treat that, you don't treat that with levy, right? It's something you don't treat with levy. And then one thing I guess I forgot to mention is, what if you see like a micro-city canemia in an if-month old child that is getting cow's milk in his diet? Well, if you see that, you want to think about eye-own deficiency anemia, right? Cow's milk, again, I didn't say cow's milk is from, like I said, cow's milk has a very strong association on NBM means with a child developing eye-own deficiency anemia. So, one of these rare things you want to keep at the back of your mind for, for NBM exams. Something again, definitely want to keep in mind for NBM exams. So, I think I've pretty much discussed everything I want to say from this breastfeeding and John Dis's perspective. And remember, you don't do photo therapy for direct type-abular bina, when I establish that again, you do not do photo therapy for direct type-abular bina in a new born on NBM exams. It doesn't work. It only works for indirect type-abular bina.

So, again, as I do at the end of every podcast, I do offer these, again, comprehensive courses for step two, seek-and-step three. And I also help with applications, like ERAS applications, personal statements and things of that nature. Again, I've worked with people for years. People with red flags, tricky applications and things like that. And there are many successful residents now in residency that I've definitely worked with, with very, you know, in the less competitive and also in the more competitive specialties. So, if that's something you're interested in, again, just shoot me an email through the website and I'll be happy to give you some more information. And again, I also have these podcasts, an Apple podcasts, or Google podcasts, and Spotify. So, please subscribe to those, at least the most recent 150 podcasts will be on there. If you want everything from episode one, go to the website, go to the website. It's a Word Press rule. There's really nothing I can do to circumvent it. And then one other thing I would like to say is I do have a You Tube channel. It's called Divine Intervention, USMLE podcasts and videos. And basically, that's where I put all my videos. That's where I essentially put all my videos. If you go there, you see like my internal medicine videos, my surgery videos, and all those things. Although the slides that go along with those videos are classically on the website. Again, go on the website and you'll find those.

And then again, if you want to get an email notification whenever I make a new podcast, just go to the website, the www.Vine Intervention Podcast.com, podcastwithens.com and subscribe. Once you subscribe, you get an email notification whenever I make a new podcast. So, thank you for listening. I just want to share a quick life lesson today. And my life lesson today is on the importance of being discreet. I know I've kind of alluded to this in some other prior podcasts, but this is something that people don't think about much. I don't know. I feel like we live in this social media generation where everything about a person's life, they put it online. If they meet a new person, a new relationship person, they put it online. If they, if they've brought, like basically you can get used to some many facts about some people's lives just by looking at the social media page, right? If they've just recently gone through a break up, you're going to see, you're going to know online, right? You're just going to be able to tell. If they celebrate their birthday, you're going to be able to tell. If they do this, again, I'm not saying you should not celebrate your accomplishments. But the thing is, there is a lot of jealousy in this world if you don't know there is definitely a lot of jealousy in this world, right? So I just feel like there are certain details of your life that doesn't have to be put in the public eye, that doesn't have to be thrown in, thrown on social media, right?

Because many times you see, like, oh, let's say a person is running for public office, right? And you see immediately the competing candidate is like, what's my next best step in management? Let me go and find some dirt that I can dig up on this person, right? But the thing is, this is especially important for people that are involved in medicine. Because as a medical professional, who has a pressing that is applying to residency in the future, right? Whether you like it or not, other residents that may be interviewing you, let's say they say, oh, you know, a resident is going to be part of admissions committee or the program director or the members of the residency selection committee. One thing they routinely do is to just check a person's social media presence, right? So if for example, they see a picture of you on social media or a video of you on social media, like you at the beach, you're popping a ton of alcohol or you're smoking marijuana or whatever, that's usually not wise, right? That can be like the sole reason why they take your application and throw it in the trash, right? So that's one thing I think I will encourage you to keep in mind, just be discreet, right? Be discreet. That is one thing, I mean, maybe my background being an Nigerian has thought me like loud and clear. But I've seen many people's lives destroyed just because they were not discreet, right? I mean, like if you even look at the, if you even look at the Bible, right?

You know, if you know, for those people that you know studied the Bible a lot, you'll see that there's a part of the Bible where some people came from Babylon to visit Hezekiah and Hezekiah was one of the kings of Israel back in the day. He showed them all his treasures, showed them the temple of God, showed them everything. But God just ties him for that and it was not too long after that. That those same people that he showed off all those things too, they came and essentially took the Israelites into captivity, right? So it's just something to kind of be mindful of, right? Like if he was discreet, maybe that would not have happened, right? God was not very pleased with him, right? So I'm just encouraging you because when you are applying with this era's process, like again, people look, oh, what is this person about? What does this person do for a living? How does this person's behavior, what kind of friends does, what kind of company does this person keep, right? How does this person spend their leisure? Is this person like very loud and very obtrusive on social media, right? There are people of like that are super opinionated, very strong opinions. Again, those kinds of things come off the wrong way to residency programs. So I'll just encourage you to be really, really, really, really careful. And then another thing I should also speak to is just being wise with drug use, right? Again, don't get me wrong.

Like I'm not going to start talking about drug abuse or whatever, but I'll just see this because this pops up, you know, you see a thread on Reddit or an SD and every now and then about a person that just marched into residency and then they need to do your in-drucks screen and then it's positive for my R1. I'll encourage you again, if you're a person that uses weed and want to go into the healthcare system, BY's, BY's, right? I'll encourage you because again, it can be little things like that that can completely destroy a person's future, right? Is the kind of thing that, oh, they see it and then they're like, oh, sorry, we're going to go ahead and rescind this residency spot that we're giving to you. Me sound unfair, probably, right? But again, they have it if you're right. Again, the thing is residency is a seller's market, right? Like, residency applications are a seller's market. Like, if they notice that you are not very serious with the process, there is a couple hundred more people that will be willing to take that spot that you just pissed away, right? So, again, just be wise, right? Because if there's something you've worked for so hard in your life, why would you use like the fact that, oh, you're using my R1 to completely throw that away, right? Because think of it for example, you've probably spent four years in underground studying extremely hard to get like perfect scores and crush the MCAT.

So, people even take a year of to study for the MCAT, do research all these shadowing and stuff you did. And then going to med school, you studied for a long time to dwell on step one, on step two, CK, dwell on your preclinical exams, dwell on your shelf exams, you have to go into the hospital all the time. Why would you want to piss that away because of something small that you could potentially live without for just just be wise, just say just be wise because the thing is there are just many unfortunate decisions that people in medicine take and then it just completely like short circuits their future. Like, I'm not saying that some people do that, kind of kills their future is you see people, they are studying for any of the USMLA exams, again, sorry, I'm kind of going on a sub-so box here, but I kind of feel like these things are kind of important, right? You see people, they know that if they think like one or two practice exams and they are barely passing their practice exams, but then they take the scope and pray that you know what I'm going to I'm going to trust that I'm going to do really well on test day. Like they magically like, oh, let's say they're studying for step two CK and they've been getting like two or five on their practice tests or two 12s, they're like barely passing practice tests. And then the miracle loss will be lived that you'll get a 240 on exam day. Well, guess what? You're putting yourself in a very tough spot.

You're literally putting yourself in a very tough spot, right? So again, don't look for these kinds of miracles, right? Don't look for these kinds. Again, I'm not saying I definitely believe in miracles, you know, I'm a Christian, right? And miracles definitely do happen, right? But again, like, if you know you're not doing well on your practice exams, you need to go back and check your study process, right? You need to go back and check your study process where you missing it, where you're doing things wrong. So hopefully you found this podcast to be helpful against a pretty high-yield podcast. So I'll see you in the next episode. Thank you. God bless you.

Practice questions — USMLE style

Question 1 — Neonatology/Metabolism

A 3-day-old neonate is admitted with jaundice. Laboratory studies reveal a total bilirubin of $8 \text{ mg/dL}$, with an indirect fraction of $7 \text{ mg/dL}$ and a direct fraction of $1 \text{ mg/dL}$. The baby has been breastfeeding adequately, but the parents are concerned about the yellowing skin. Which of the following statements regarding the management of this neonate is most accurate?

  • A) Since the bilirubin is predominantly indirect, phototherapy should be initiated immediately to prevent kernicterus.
  • B) Because the direct bilirubin fraction is elevated, the jaundice must be considered pathological and requires immediate exchange transfusion.
  • C) The primary concern is increased enterohepatic recirculation due to inadequate gut clearance of unconjugated bilirubin.
  • D) Given the age and low total bilirubin level, no intervention is necessary as this pattern suggests physiologic jaundice.

Answer: C. Explanation: The neonate has indirect hyperbilirubinemia (unconjugated). While phototherapy is indicated for significant levels, the underlying mechanism in early life, especially when associated with poor feeding or dehydration (as implied by "breastfeeding jaundice"), involves increased enterohepatic recirculation of unconjugated bilirubin. This process increases the amount of bilirubin available to accumulate in the blood. Option A is incorrect because while phototherapy may be needed at higher levels, simply stating it should be initiated immediately without knowing the risk stratification is incomplete. Option B is incorrect because a direct fraction of $1 \text{ mg/dL}$ on day 3 is not significantly elevated enough to mandate immediate exchange transfusion; furthermore, the primary issue here is unconjugated hyperbilirubinemia. Option D is incorrect because while physiologic jaundice exists, the specific context (early life, potential dehydration) points toward a mechanism that requires monitoring and intervention if levels rise.

Question 2 — Obstetrics/Infectious Disease

A 34-year-old woman presents to the clinic two days postpartum with unilateral breast tenderness, erythema, and localized warmth over her right breast quadrant. She reports feeling generally unwell and has a temperature of $102^{\circ} \text{F}$. On physical examination, there is no palpable mass, but she notes significant pain upon palpation in that area. Which of the following diagnoses is most likely?

  • A) Breast abscess, requiring immediate incision and drainage (I&D).
  • B) Mastitis, which should be managed primarily with supportive care and continued breastfeeding.
  • C) Engorgement, as this condition typically presents unilaterally postpartum.
  • D) Pneumonia, given the patient's fever and localized breast symptoms.

Answer: B. Explanation: The clinical presentation of unilateral tenderness, erythema, and warmth in a postpartum woman is classic for mastitis. Mastitis is most commonly caused by Staphylococcus infection. Management involves supportive care (analgesics) and continued breastfeeding to help clear the infection. Option A describes an abscess, which typically presents with fluctuance or a palpable mass, not just tenderness. Option C is incorrect because engorgement usually presents as a bilateral process. Option D is incorrect because while fever is present, the symptoms are localized specifically to the breast tissue.

Question 3 — Pediatrics/Nutrition

A child is diagnosed with essential galactosemia due to deficient galactonolactone transferase activity. The child requires specialized nutritional support and cannot tolerate standard milk formulas containing lactose. Which type of formula should be administered?

  • A) Soy protein-based formula, as it provides an alternative source of amino acids.
  • B) Amino acid-based formula, which bypasses the need for carbohydrate metabolism.
  • C) Protein hydrolysate formula, due to potential gut barrier issues associated with galactosemia.
  • D) Lactulose solution, used to manage osmotic diarrhea secondary to metabolic derangement.

Answer: B. Explanation: Essential galactosemia is a disorder of carbohydrate metabolism where the inability to process galactose leads to toxic buildup (galactose-1-phosphate). Since standard milk formulas contain lactose (a disaccharide composed of glucose and galactose), these must be avoided. Amino acid-based formulas provide all necessary building blocks for protein synthesis without containing carbohydrates that require galactonolactone transferase activity, making them the safest choice. Option A is incorrect because soy still contains lactose. Option C is generally used when there are severe gut permeability issues (like in celiac disease or NEC), but amino acids address the core metabolic defect here.

Question 4 — Neonatology/Pathophysiology

A neonate presents to the clinic on day 5 of life with indirect hyperbilirubinemia and mild jaundice. The baby is noted to be feeding infrequently, receiving small amounts of milk every 4-6 hours. Which pathophysiological mechanism best explains this pattern of elevated unconjugated bilirubin?

  • A) Increased activity of UDP-glucuronosyltransferase (UDPGT) in the liver due to neonatal immaturity.
  • B) Hemolysis resulting from Rh incompatibility, overwhelming hepatic conjugation capacity.
  • C) Decreased gut motility leading to decreased enterohepatic recirculation of conjugated bilirubin.
  • D) Dehydration and poor feeding leading to increased gastrointestinal transit time and subsequent reabsorption of unconjugated bilirubin.

Answer: D. Explanation: This clinical picture is characteristic of "breastfeeding jaundice" (or inadequate intake jaundice). The pathophysiology involves dehydration and insufficient caloric/fluid intake, which slows gut motility and increases the enterohepatic recirculation of unconjugated bilirubin. Instead of being excreted in stool, more unconjugated bilirubin is reabsorbed into the circulation, leading to elevated levels. Option A is incorrect; UDPGT activity is low in neonates, contributing to jaundice, but this does not explain the specific pattern related to poor feeding. Option B describes hemolytic jaundice, which would typically present with a different clinical picture and often involves direct evidence of hemolysis (e.g., anemia). Option C is incorrect because increased enterohepatic recirculation increases bilirubin levels; decreased motility leads to increased reabsorption.

Quick fire review

What is the minimum recommended duration for exclusive breastfeeding according to USMLE guidelines?

At least six months.

Which immune factor, found in breast milk, is highly associated with decreased risk of infections like pneumonia or meningitis in the baby?

Immunoglobulin A (IgA).

In a postpartum woman, what process does prolonged breastfeeding help suppress, thereby decreasing the risk of ovarian and breast cancer?

The Hypothalamic-Pituitary-Gonadal (HPG) axis by suppressing GnRH.

What is the key difference in presentation between mastitis and a breast abscess?

Mastitis is typically unilateral tenderness; an abscess presents with fluctuation/a palpable mass.

If a child has jaundice within the first 24 hours of life, what type of jaundice is it, and how should it be classified?

Pathologic jaundice (always pathologic).

What mechanism allows phototherapy to treat hyperbilirubinemia?

It converts water-insoluble conjugated bilirubin into water-soluble forms.

Which specific deficiency causes megaloblastic anemia in a child fed exclusively on goat or cow milk?

Vitamin D and/or Iodine (leading to potential iodine deficiency).

What is the primary contraindication for breastfeeding related to chemotherapy?

Chemotherapy destroys rapidly dividing cells, which could harm the neonate.

Name three absolute contraindications to breastfeeding on USMLE exams.

Active TB, HIV, active herpes lesions, or maternal cancer treatment (chemotherapy).

What is the key difference in bilirubin type that phototherapy can treat?

It only works for indirect (unconjugated) hyperbilirubinemia; it does not work for direct (conjugated) hyperbilirubinemia.

Why is a child who is dehydrated due to infrequent breastfeeding at risk for jaundice during the first week of life?

Dehydration increases GI transit time, leading to increased enterohepatic recirculation of bilirubin.

What type of formula should be given to a child with severe protein malabsorption (e.g., short gut syndrome)?

Amino acid-based formula.

If a baby is fed exclusively on goat or cow milk and develops megaloblastic anemia, what deficiency is suspected?

Vitamin D or Iodine deficiency.

What specific enzyme deficiency causes essential galactosemia?

Galactosamine-1-phosphate uridyl transferase.

Quick recall / Anki-style questions

What is the primary contraindication for breastfeeding related to chemotherapy?

Chemotherapy destroys rapidly dividing cells, which could harm the neonate.

Name three absolute contraindications to breastfeeding on USMLE exams.

Active TB, HIV, active herpes lesions, or maternal cancer treatment (chemotherapy).

What is the key difference in bilirubin type that phototherapy can treat?

It only works for indirect (unconjugated) hyperbilirubinemia; it does not work for direct (conjugated) hyperbilirubinemia.

Why is a child who is dehydrated due to infrequent breastfeeding at risk for jaundice during the first week of life?

Dehydration increases GI transit time, leading to increased enterohepatic recirculation of bilirubin.

What type of formula should be given to a child with severe protein malabsorption (e.g., short gut syndrome)?

Amino acid-based formula.

If a baby is fed exclusively on goat or cow milk and develops megaloblastic anemia, what deficiency is suspected?

Vitamin D or Iodine deficiency.

What specific enzyme deficiency causes essential galactosemia?

Galactosamine-1-phosphate uridyl transferase.