Henoch Schonlein purpura presenting with pulmonary haemorrhage.

A young woman presented with arthralgia, a rash and dramatic haemoptysis, and renal involvement was indicated by proteinuria, haematuria and a rising serum creatinine. A systemic vasculitic disorder was suspected initially, but the diagnosis of Henoch-Schonlein purpura was established by the finding of mesangial IgA deposits on renal biopsy. Immunofluorescent study of renal biopsy material is vital to diagnosis where the clinical features of Henoch-Schonlein purpura and those of the systemic vasculitides with renal involvement prove to be indistinguishable.