Henoch-Schonlein purpura and streptococcal infection: a prospective case-control study

A prospective, matched, case-control study conducted over a period of 3 yea rs was designed to examine the association of group A P-haemolytic streptoc occal infections and Henoch-Schonlein purpura. Demographic and clinical dat a were collected as well as measurement of antistreptolysin O titres and th roat swab culture on all children admitted with Henoch-Schonlein purpura, a s well as their matched controls. Antistreptolysin O titre positivity was a ssociated with a 10-fold increase in the risk of Henoch-Schonlein purpura. Renal involvement was common among cases with positive antistreptolysin O t itres (27%) compared with cases with a negative titre (8%) but this differe nce has no statistical significance.