[Acute hemorrhagic edema of childhood and its differentiation from Schoenlein-Henoch purpura].

In two young patients with an elevated temperature, a girl aged 6 months and a boy aged 10 months, purpura and oedema were noticed on the face, ears, arms and legs. On one occasion the boy lost blood anally. A histopathological examination revealed leucocytoclastic vasculitis with fibrin deposits. The diagnosis was 'acute haemorrhagic oedema of infancy' (AHOI), a relatively unknown variant of palpable purpura due to leucocytoclastic vasculitis affecting infants and young children (up to two years of age). AHOI is characterised clinically by marked oedema and fever as well as large palpable purpuric and ecchymotic skin lesions in a target-like pattern mainly on the face, ears and extremities. The skin lesions heal spontaneously within one to three weeks and internal organs are rarely affected. This is in contrast to Henoch-Schönlein purpura, which was observed in a 5-year old boy suffering from similar skin lesions on the legs as well as painful joints, in whom IgA deposits were found in the vasculitis. Henoch-Schönlein purpura is clinically characterised by palpable purpura on the extensor surfaces of the legs and on the buttocks, whereas in AHOI larger purpura and ecchymoses are found on the face, ankles and wrists, with far more extensive oedema. There are also histological differences: in AHOI there is more extensive vasculitis with fibrin deposits and IgA deposits are seen in a minority of cases. Awareness of this relatively unknown form of leucocytoclastic vasculitis will assist in making an early diagnosis possible, thereby avoiding unnecessary treatment and concern.