STREPTOCOCCAL PYROGENIC EXOTOXIN-A, STREPTOLYSIN-O, EXOENZYMES, SEROTYPE AND BIOTYPE PROFILES OF STREPTOCOCCUS-PYOGENES ISOLATES FROM PATIENTS WITH TOXIC-SHOCK-SYNDROME AND OTHER SEVERE INFECTIONS

The determination of protein M and T serotypes, biotypes and pyrogenic (erythrogenic) exotoxin A (SPE A), streptolysin O (SLO), streptokinas e (SK), hyaluronidase (HA) and cysteine proteinase release by 212 S. p yogenes isolates from patients with severe invasive group A streptococ cal (GAS) infections, among them 74 cases of streptococcal toxic shock syndrome (STSS) has been investigated. M1 or M3 serotypes were expres sed by 25% of the isolates (53/212), whereas 59% (125/212) belonged to 15 other different serotypes and 16% (34/212) were untypeable. Of the 74 isolates from STSS patients, 42% (31/74) expressed M1 and to a les ser extent M3 serotypes versus 19% of the non STSS isolates (26/138). Among the ten different biotypes known, biotypes 1 and 3 were prevalen t, particularly the former in the case of STSS isolates. SPE A was det ectably produced by about 25% (54/212) of the strains. However, as hig h as 40.5% of the STSS isolates (30/74) versus 17.4% of non STSS isola tes (24/138) released SPE A. Moreover, 67% of the SPE A producing stra ins were of serotype M1 or M3. SK and HA were released by 71% and 10% of the isolates respectively. All strains released SLO (4 to 256 HU/ml ) and 85% cysteine proteinase. No relationship between toxin or enzyme titer and the type of disease or clinical origin of the strains was f ound. Culture supernatants of all isolates showed moderate to high lym phocyte transforming activity with index values ranging from 14.5 to 5 0.3 including those strains which did not release detectable amounts o f SPE A suggesting that SPE C and other mitogenic factor(s) are releas ed by the isolates investigated.