HLA-B27 Spondylitis
Ankylosing Spondylitis: young male, inflammatory back pain improved with exercise, bamboo spine, sacroiliitis, acute anterior uveitis, restrictive lung defect.
Reactive Arthritis Triad
'Can't see, can't pee, can't climb a tree': Anterior uveitis, urethritis/cervicitis (Chlamydia/Campylobacter), asymmetric oligoarthritis + dactylitis.
Large Vessel Vasculitis
Giant Cell Arteritis (age > 50, jaw claudication, ESR > 100, temporal artery biopsy; immediate IV steroids). Takayasu: pulseless disease in young Asian females.
Seronegative Spondyloarthropathies (HLA-B27)
| Condition | Epidemiology & HLA Association | Clinical Manifestations & Radiography | First-Line Medical Therapy |
|---|---|---|---|
| Ankylosing Spondylitis (AS) | Young men (20–40); HLA-B27 > 90% positive; negative RF and ANA | Inflammatory low back pain (worse with rest/morning, improves with exercise); reduced lumbar flexion (Schober test < 5 cm); bilateral sacroiliitis; bamboo spine (syndesmophytes); aortitis, apical lung cysts | NSAIDs (first-line); TNF-alpha inhibitors (Infliximab, Adalimumab) or IL-17 inhibitors (Secukinumab) for refractory disease |
| Psoriatic Arthritis (PsA) | 30% of patients with psoriasis; asymmetric oligoarthritis or symmetric polyarthritis | Dactylitis ('sausage digits'), enthesitis (Achilles tendonitis), penciling of distal interphalangeal (DIP) joints ('pencil-in-cup' deformity), nail pitting, onycholysis | NSAIDs → Methotrexate → TNF-alpha inhibitors; avoid oral corticosteroids (can precipitate pustular psoriasis flares) |
| Reactive Arthritis (Reiter) | Post-infectious: enteric (Shigella, Salmonella, Yersinia, Campylobacter) or genitourinary (Chlamydia trachomatis) | Classic Triad: 1. Asymmetric oligoarthritis, 2. Urethritis / cervicitis, 3. Conjunctivitis / uveitis; Keratoderma blennorrhagicum (hyperkeratotic palms/soles), circinate balanitis | NSAIDs; treat triggering Chlamydia infection with Doxycycline; antibiotics do not accelerate joint resolution once established |
Vessel-Size Vasculitis Algorithmic Classification
| Vessel Size & Vasculitis | Target Vessels & Autoantibody | High-Yield Clinical Hallmarks | First-Line Management |
|---|---|---|---|
| Giant Cell (Temporal) Arteritis (Large) | Branches of carotid artery (temporal, ophthalmic); high ESR (> 50–100 mm/hr) | Age > 50; new unilateral temporal headache, scalp tenderness, jaw claudication, amaurosis fugax; associated with polymyalgia rheumatica (PMR) | Immediate high-dose systemic steroids (oral Prednisone 60 mg/day or IV Methylprednisolone if vision changes) BEFORE temporal artery biopsy |
| Takayasu Arteritis (Large) | Aortic arch and its primary branch origins; elevated ESR/CRP | Young Asian female (< 40); 'pulseless disease' (diminished upper extremity pulses, BP discrepancy > 10 mmHg between arms), lightheadedness, bruits over subclavian arteries | High-dose systemic corticosteroids ± Methotrexate or TNF inhibitors; surgical bypass or angioplasty for critical vessel stenosis |
| Polyarteritis Nodosa (PAN) (Medium) | Medium-sized muscular arteries (renal, mesenteric); associated with Hepatitis B (HBV); ANCA negative | Hypertension, livedo reticularis, renal microaneurysms without glomerulonephritis, mononeuritis multiplex (foot/wrist drop), mesenteric ischemia; spares pulmonary vasculature | Systemic corticosteroids + Cyclophosphamide; treat underlying Hepatitis B infection (Entecavir / Tenofovir) |
| Granulomatosis with Polyangiitis (GPA) (Small) | Nasopharynx, lungs, kidneys; c-ANCA / anti-Proteinase-3 (PR3) | Upper airway: Chronic sinusitis, saddle-nose deformity, bloody nasal discharge; Lower airway: Cavitary lung nodules, hemoptysis; Renal: Rapidly progressive crescentic glomerulonephritis | High-dose Corticosteroids + Rituximab or Cyclophosphamide |
| Henoch-Schönlein Purpura (IgA Vasculitis) (Small) | Small postcapillary venules; IgA immune complex deposition | Children post-URI; Tetrad: 1. Palpable purpura on buttocks/lower extremities, 2. Colicky abdominal pain/intussusception, 3. Arthralgias, 4. Hematuria (IgA nephropathy) | Supportive care, hydration, NSAIDs; systemic corticosteroids for severe abdominal pain or progressive glomerulonephritis |
OMM Board Correlate: Sacroiliac Articulation & Rib Compliance in Spondylitis
- Sacroiliitis & Ligamentous Tension: Early ankylosing spondylitis initiates with bilateral sacroiliitis. Release of the sacrotuberous and sacrospinous ligaments via gentle myofascial techniques relieves lumbopelvic torque.
- Costovertebral Fusion: In progressive AS, fusion of costovertebral and costotransverse articulations severely restricts chest expansion (< 2.5 cm measured at 4th intercostal space). Regular gentle rib raising and muscle energy for ribs preserve thoracic cage compliance and vital capacity.
- HVLA Contraindication: High-Velocity Low-Amplitude (HVLA) thrust is ABSOLUTELY CONTRAINDICATED in advanced ankylosing spondylitis due to risk of catastrophic spinal fracture, epidural hematoma, and spinal cord transection.
Board Traps & Common Distractors
- In suspected Giant Cell Arteritis with visual symptoms, NEVER delay systemic corticosteroid therapy to await temporal artery biopsy; ischemic optic neuropathy leads to permanent, irreversible blindness within hours.
- Palpable purpura without thrombocytopenia is the clinical hallmark of leukocytoclastic small-vessel vasculitis (HSP / IgA vasculitis), distinguishing it from thrombocytopenic purpura (ITP/TTP) where purpura is flat and non-palpable.
- Never perform HVLA manipulation on patients with established inflammatory spondyloarthropathies, Down syndrome, or rheumatoid arthritis due to high risk of atlantoaxial (AA) subluxation and dens-mediated spinal cord compression.