W. Tewodros et G. Kronvall, DISTRIBUTION OF PRESUMPTIVE PATHOGENICITY FACTORS AMONG BETA-HEMOLYTIC STREPTOCOCCI ISOLATED FROM ETHIOPIA, APMIS. Acta pathologica, microbiologica et immunologica Scandinavica, 101(4), 1993, pp. 295-305
Beta-hemolytic streptococci are known to bind several mammalian protei
ns, which are presumed to be important in pathogenicity. The distribut
ion of such binding structures was examined for mouse albumin, human s
erum IgA, human IgG, human fibrinogen, and human plasminogen. A total
of 218 group A beta-hemolytic streptococci (GAS) were studied: 5 isola
tes from children with acute rheumatic fever (ARF), 18 from acute post
-streptococcal glomerulonephritis (APSGN), 57 from tonsillitis, 52 fro
m skin infections, and 86 from healthy carriers. Sixty-eight Streptoco
ccus equisimilis and 20 group G streptococci were also included. Most
of the S. equisimilis (60/68) and group G (14/20) were obtained from a
pparently healthy carriers. The results were evaluated with respect to
T type, serum opacity reaction (SOR), site of isolation, and disease
type. No direct correlation was detected between the protein-binding s
tructures studied. There was no apparent correlation between any parti
cular protein-binding structure and specific T type. Albumin-binding a
nd IgA-binding activities were inversely correlated among skin and nep
hritis GAS isolates. A strong correlation was demonstrated between IgA
-binding activity and SOR production, while albumin-binding activity c
orrelated with SOR-negative strains. Albumin-binding levels in isolate
s from ARF, APSGN and tonsillitis were significantly higher than in is
olates from healthy carriers (P<0.001). A higher albumin-binding capac
ity was shown in skin isolates from APSGN than in isolates from impeti
go (P < 0.001).