In vivo attachment of group A streptococci to tonsillar epithelium during acute tonsillitis.

The attachment of group A beta-hemolytic streptococci (GABHS) to the tonsillar epithelium during current acute tonsillitis (AT) was studied by means of fluorescence microscopy and electron microscopy in 5 patients. Conventional cultures from the tonsils showed massive growth of GABHS and tonsillar epithelial cells were heavily infested with GABHS, which proved positive for FITC-labelled antibodies against beta-hemolytic streptococci. The bacteria were firmly attached to the epithelial cell membranes by cell projections, which grasped the microorganisms from various directions. A 24 h course of oral treatment with phenoxymethylpenicillin radically affected bacterial adherence to the epithelial cells.