Tropical acute rheumatic fever and associated streptococcal infections compared with concurrent acute glomerulonephritis.

Ninety-three patients with acute rheumatic fever and 195 patients with acute glomerulonephritis were observed in Trinidad during an outbreak of scabies with a high incidence of secondary streptococcal infections. Clinical and laboratory manifestations of ARF were the same as those seen in temperate zones, except that antistreptolysin O titers were less markedly increased. The patients with ARF were similar to those with AGN in respect to sex, race, location of residence, and living conditions, but were older and had markedly fewer skin infections. Currently prevalent nephritogenic streptococcal strains never were isolated from patients with ARF even when M55 streptococci appeared and led to an epidemic of AGN.