Case 46 - Henoch–Schönlein purpura

Summary

Imaging description

A seven-year-old boy presented with nausea and acute, colicky abdominal pain. The medical history revealed a pharyngitis a few weeks ago and the clinical examination demonstrated multiple small purpura (small areas of hemorrhage) of the skin of the buttocks and upper thighs. An upper gastrointestinal (GI) study demonstrated “thumbprinting” of the duodenum (Fig. 46.1). CT images from another patient after oral contrast media administration demonstrate marked mural thickening of a loop of ileum with narrowing of the lumen and some adjacent free fluid (Fig. 46.2).

Importance

Henoch–Schönlein purpura is a disease of young children (50% are younger than six years of age and 90% are younger than 10 years of age), which typically occurs after an upper respiratory tract infection. The infection leads to formation of complexes of IgA and complement component 3, which accumulate in small vessels and cause a small-vessel vasculitis of the skin, joints, GI tract, and sometimes the kidneys. Acute GI symptoms may precede typical cutaneous lesions in 10–15% of patients and may lead to a laparotomy. It is important to recognize typical clinical and imaging findings of this disease, since it usually resolves spontaneously and does not require invasive interventions.