Correct Answer: A. Glucocorticoids
The clinical presentation—palpable purpura over lower limbs, arthralgia, abdominal pain, and preceding upper respiratory tract infection—is pathognomonic for IgA vasculitis (formerly Henoch-Schönlein purpura, HSP). This is a small-vessel vasculitis mediated by IgA immune complex deposition in skin, joints, GI tract, and kidneys. The diagnosis is clinical; the preceding URTI is a classic trigger in children. Glucocorticoids are the first-line and standard treatment for IgA vasculitis, particularly when systemic involvement (GI symptoms, arthritis) is present. Corticosteroids suppress the inflammatory cascade, reduce IgA immune complex formation, and prevent progression to renal disease. In Indian pediatric practice (IAP guidelines), oral prednisolone 1–2 mg/kg/day is initiated; severe cases or renal involvement warrant IV methylprednisolone pulses. The evidence base (including Indian case series) demonstrates that early corticosteroid therapy reduces the risk of IgA nephropathy progression and long-term renal morbidity. NSAIDs may be used adjunctively for joint pain, but corticosteroids remain the cornerstone of therapy.
Why the other options are wrong
B. Cyclosporine — Cyclosporine is a calcineurin inhibitor used in steroid-refractory or steroid-dependent IgA vasculitis, typically reserved for recurrent renal flares or progressive IgA nephropathy despite corticosteroids. It is never first-line; using it as initial therapy would delay effective anti-inflammatory treatment and expose the child to unnecessary immunosuppression without addressing the acute inflammatory phase. C. Methotrexate — Methotrexate is a disease-modifying antirheumatic drug (DMARD) used in chronic rheumatologic conditions (e.g., juvenile idiopathic arthritis) and steroid-sparing strategies in refractory vasculitis. It has no role in acute IgA vasculitis; it is slow-acting (weeks to months) and inappropriate for acute systemic vasculitis requiring rapid anti-inflammatory control. D. Azathioprine — Azathioprine is a purine antagonist used as a steroid-sparing agent in chronic or recurrent IgA vasculitis with renal involvement, not as initial therapy. Like methotrexate, it is reserved for steroid-dependent cases or to reduce long-term corticosteroid burden, not for acute presentation with active systemic symptoms.
High-Yield Facts
- IgA vasculitis (HSP) is the most common systemic vasculitis in children; diagnosis is clinical (palpable purpura + arthralgia ± GI/renal involvement) with preceding URTI.
- Glucocorticoids (prednisolone 1–2 mg/kg/day) are first-line therapy; they reduce IgA immune complex deposition and prevent progression to IgA nephropathy.
- Renal involvement (IgA nephropathy) occurs in ~40–50% of children; early corticosteroid therapy reduces the risk of chronic kidney disease.
- Cyclosporine, methotrexate, and azathioprine are steroid-sparing or steroid-refractory agents, not first-line; they are reserved for recurrent flares or renal progression.
- NSAIDs may be used adjunctively for joint pain but are avoided if renal involvement or GI bleeding is present.
Mnemonics
HSP (IgA Vasculitis) Triad P-A-R: Purpura (lower limbs, buttocks), Arthralgia (knees, ankles), Renal (IgA nephropathy). Add GI involvement (abdominal pain) = systemic disease → corticosteroids needed. Vasculitis Treatment Ladder First-line: Corticosteroids (all acute vasculitis). Second-line: NSAIDs (adjunctive). Third-line: Steroid-sparing agents (cyclosporine, methotrexate, azathioprine) only if steroid-refractory or steroid-dependent.
NBE Trap
NBE may pair IgA vasculitis with immunosuppressive agents (cyclosporine, methotrexate, azathioprine) to trap students who confuse acute vasculitis management with chronic rheumatologic disease management. The key discriminator is acute systemic inflammation → corticosteroids; chronic/refractory disease → steroid-sparing agents.
Clinical Pearl
In Indian pediatric practice, a child presenting with the classic tetrad of palpable purpura (lower limbs), arthralgia, abdominal pain, and preceding URTI should be started on oral prednisolone immediately; renal screening (urinalysis, creatinine) is done in parallel. Early corticosteroid therapy in the first 2 weeks significantly reduces the risk of IgA nephropathy progression and long-term renal morbidity—a critical outcome in resource-limited settings where dialysis access is limited.
_Reference: OP Ghai (Pediatrics) Ch. Vasculitis; IAP Guidelines on IgA Vasculitis; Harrison Ch. 319 (Vasculitis)_