Diagnosis of invasive group a streptococcal infections by using immunohistochemical and molecular assays.
Invasive group A streptococcus (GAS) infections cause 1,100 to 1,300 deaths annually in the United States. Diagnosis is made when Streptococcus pyogenes is isolated from pus or body fluids; however, cultures are not always obtained, and antibiotic treatment can preclude bacterial growth. An immunohistochemical assay for GAS was applied to formalin-fixed tissue samples from 122 patients with suspect GAS infection. Immunohistochemical staining of well-defined cocci and small, granular antigen fragments was observed in 27 cases. S pyogenes was isolated in 18 cases, whereas in 8 cases, immunohistochemical staining was confirmed by amplification of the sepB gene of S pyogenes from paraffin-embedded samples in a heminested polymerase chain reaction (PCR) assay. A primary focus of infection (respiratory, mucocutaneous, or gynecologic) was present in 22 patients, whereas 5 had no identifiable primary focus of infection. Eighteen patients had systemic infection. Immunohistochemical analysis and PCR can be used for diagnosis of GAS infections in formalin-fixed, paraffin-embedded samples.
Guarner
Jeannette
J
Infectious Disease Pathology Activity, National Centers for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA.
Sumner
John
J
Paddock
Christopher D
CD
Shieh
Wun-Ju
WJ
Greer
Patricia W
PW
Reagan
Sarah
S
Fischer
Marc
M
Van Beneden
Chris A
CA
Zaki
Sherif R
SR
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D004269:DNA, Bacterial / Q000032:analysis; D005260:Female; D005557:Formaldehyde; D005798:Genes, Bacterial / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D007223:Infant; D008297:Male; D008875:Middle Aged; D025202:Molecular Diagnostic Techniques; D010338:Pathology, Clinical / Q000379:methods*; D016133:Polymerase Chain Reaction; D013290:Streptococcal Infections / Q000175:diagnosis* / Q000382:microbiology; D013297:Streptococcus pyogenes / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D016707:Tissue Fixation
D004269:DNA, Bacterial; D005557:Formaldehyde