Haemolysin And Enzyme Patterns Of Coagulase-Positive Staphylococci Isolated From Toxic Epidermal Necrolysis, Ritter'S Disease And Impetigo Contagiosa

Strains of Staphylococcus aureus isolated from toxic epidermal necrolysis and Ritter's disease (named collectively “ Ritter's type ” of TEN) and from extensive cases of impetigo contagiosa, in which the diagnosis of Ritter's type of TEN was considered seriously, were assigned to group E (extensive lesions) and were compared with strains of S. aureus isolated from unequivocal impetigo contagiosa (group L—localised lesions); 24 of the 26 isolates examined belonged to phage-group II.

Strains from groups E and L were generally similar in their patterns of proteolytic activity, low incidence of positive egg-yolk reaction, possession of lipase and production of hyaluronidase. The difference lay in the many isolates in group E that produced a low-titre lysin active against rabbit red cells that was not α-haemolysin. The average titre of lysin active against rabbit erythrocytes in group E was 355 MHD per mi and in group L 1008 MHD per mi. Reasons are given for supposing that this low titre rabbit cell lysin is identical with staphylococcal δ-toxin. It is suggested that δ-toxin may play a part in the pathogenesis of Ritter's type of TEN and extensive impetigo.