Isolation ratio and T- serotyping of group A streptococci from pediatric upper respiratory tract infections in Turkey.
OBJECTIVE
Acute rheumatic fever can follow throat infections with group A streptococci. Certain serotypes of group A streptococci such as M1, M3, M5, M6, M14, M18, M19, M24 are associated with this disorder. Immunity to streptococci and to rheumatic fever depends on antibodies to the M proteins. Due to current scarcity of M-typing sera, many laboratories use T typing and opacity factor production for serotype identification of group A streptococci. In order to, investigate the most common serotypes of group A streptococci in our country in recent years we studied T-agglutination typing and opacity factor of 120 group A streptococci strains isolated from throat cultures of 930 children.


METHODS
Diffuse, stable suspensions of group A streptococci were tested with polyvalent antisera (T,U,W,X,Y) by slide agglutination. Microplate method was used for opacity factor detection.


RESULTS
T-protein -agglutination patterns U (2,4,6,28) were the most common among typeable strains. The rate of T-protein -agglutination patterns T (1,3,13, B3264) and X (8,14,25,Imp.19) were 20 % and 18 % respectively. Opacity factor production rate of isolated group A streptococci strains was 65%.


CONCLUSIONS
To profit global assessment of rheumatic fever and rheumatic heart disease, more epidemiological and serotyping research is required in our country.
Topkaya
Aynur Eren
AE
Department of Microbiology and Clinical Microbiology, Faculty of Medicine, University of Maltepe, Istanbul, Turkey. ty@ttnet.net.tr
Yildirim
Tekin
T
Arsan
Sinan
S
D000293:Adolescent; D000372:Agglutination Tests; D000907:Antibodies, Bacterial / Q000097:blood*; D000942:Antigens, Bacterial / Q000276:immunology*; D001425:Bacterial Outer Membrane Proteins / Q000276:immunology*; D002352:Carrier Proteins / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D010447:Peptide Hydrolases / Q000032:analysis; D012141:Respiratory Tract Infections / Q000453:epidemiology / Q000382:microbiology*; D012703:Serotyping; D013290:Streptococcal Infections / Q000453:epidemiology / Q000382:microbiology*; D013297:Streptococcus pyogenes / Q000145:classification / Q000302:isolation & purification / Q000472:pathogenicity; D014421:Turkey / Q000453:epidemiology
D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D002352:Carrier Proteins; C021908:opacity factor; C014689:streptococcal M protein; D010447:Peptide Hydrolases