Henoch-Schönlein purpura in an older man presenting as rectal bleeding and IgA mesangioproliferative glomerulonephritis: a case report

INTRODUCTION Henoch-Schönlein purpura is the most common systemic vasculitis in children. Typical presentations are palpable purpura, abdominal pain, arthritis, and hematuria. This vasculitic syndrome can present as an uncommon cause of rectal bleeding in older patients. We report a case of an older man with Henoch-Schönlein purpura. He presented with rectal bleeding and acute kidney injury secondary to IgA mesangioproliferative glomerulonephritis. CASE PRESENTATION A 75-year-old Polish man with a history of diverticulosis presented with a five-day history of rectal bleeding. He had first noticed colicky left lower abdominal pain two months previously. At that time he was treated with a 10-day course of ciprofloxacin and metronidazole for possible diverticulitis. He subsequently presented with rectal bleeding to our emergency department. Physical examination revealed generalized palpable purpuric rash and tenderness on his left lower abdomen. Laboratory testing showed a mildly elevated serum creatinine of 1.3. Computed tomography of his abdomen revealed a diffusely edematous and thickened sigmoid colon. Flexible sigmoidoscopy showed severe petechiae throughout the colon. Colonic biopsy showed small vessel acute inflammation. Skin biopsy resulted in a diagnosis of leukocytoclastic vasculitis. Due to worsening kidney function, microscopic hematuria and new onset proteinuria, he underwent a kidney biopsy which demonstrated IgA mesangioproliferative glomerulonephritis. A diagnosis of Henoch-Schönlein purpura was made. Intravenous methylprednisolone was initially started and transitioned to prednisone tapering orally to complete six months of therapy. There was marked improvement of abdominal pain. Skin lesions gradually faded and gastrointestinal bleeding stopped. Acute kidney injury also improved. CONCLUSION Henoch-Schönlein purpura, an uncommon vasculitic syndrome in older patients, can present with lower gastrointestinal bleeding, extensive skin lesions and renal involvement which responds well to systemic steroid therapy. A history of diverticulosis can mislead physicians to the diagnosis of diverticular bleeding which is more common in this age group. The clinical manifestations of the disease, including characteristic skin rash, abdominal pain, joint inflammation and renal involvement raised the suspicious of Henoch-Schönlein purpura.