Autumn--the season for post-streptococcal acute glomerulonephritis in New Zealand.

Post-streptococcal acute glomerulonephritis, which may follow either streptococcal throat or skin infection, continues to be prevalent among New Zealand school children. Group A streptococci were cultured from 41 patients with acute glomerulonephritis between 1978 and 1983. The skin was the predominant site of infection (68%). Streptococci belonging to major pyoderma-associated nephritogenic serotypes 49, 57 and 60 accounted for 19/30 (63%) M-typable isolates. A seasonal peak in hospital admissions was observed during the months April, May and June. From April to July peak rates for streptococcal skin infection also occurred during a one year community study. In this study group A streptococci were recovered from 83% of skin lesions. The predominance of pyoderma-associated nephritogenic serotypes among acute glomerulonephritis patients and their relative absence in uncomplicated skin infection implies an association with acute glomerulonephritis. We believe that streptococcal skin infection may be an important factor in the epidemiology of acute glomerulonephritis in New Zealand.