Diversity of group B streptococcus serotypes causing urinary tract infection in adults.
Serotypes of group B streptococcus (GBS) that cause urinary tract infection (UTI) are poorly characterized. We conducted a prospective study of GBS UTI in adults to define the clinical and microbiological characteristics of these infections, including which serotypes cause disease. Patients who had GBS cultured from urine over a 1-year period were grouped according to symptoms, bacteriuria, and urinalysis. Demographic data were obtained by reviewing medical records. Isolates were serotyped by latex agglutination and multiplex PCR-reverse line blotting (mPCR/RLB). Antibiotic susceptibilities were determined by disc diffusion. GBS was cultured from 387/34,367 consecutive urine samples (1.1%): 62 patients had bacteriuria of >10(7) CFU/liter and at least one UTI symptom; of these patients, 31 had urinary leukocyte esterase and pyuria (others not tested), 50 (81%) had symptoms consistent with cystitis, and 12 (19%) had symptoms of pyelonephritis. Compared with controls (who had GBS isolated without symptoms), a prior history of UTI was an independent risk factor for disease. Increased age was also significantly associated with acute infection. Serotyping results were consistent between latex agglutination and mPCR/RLB for 331/387 (85.5%) isolates; 22 (5.7%) and 7 (1.8%) isolates were nontypeable with antisera and by mPCR/RLB, respectively; and 45/56 (80.4%) isolates with discrepant results were typed by mPCR/RLB as belonging to serotype V. Serotypes V, Ia, and III caused the most UTIs; serotypes II, Ib, and IV were less common. Nontypeable GBS was not associated with UTI. Erythromycin (39.5%) and clindamycin (26.4%) resistance was common. We conclude that a more diverse spectrum of GBS serotypes causes UTI than previously recognized, with the exception of nontypeable GBS.
Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
Kimberly B
KB
Ulett
William H
WH
Benjamin
Fenglin
F
Zhuo
Meng
M
Xiao
Fanrong
F
Kong
Gwendolyn L
GL
Gilbert
Mark A
MA
Schembri
Glen C
GC
Ulett
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016172:DNA Fingerprinting; D024881:Drug Resistance, Bacterial; D005260:Female; D014644:Genetic Variation; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D012307:Risk Factors; D012703:Serotyping; D013290:Streptococcal Infections / Q000453:epidemiology / Q000382:microbiology* / Q000473:pathology / Q000503:physiopathology; D013292:Streptococcus agalactiae / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D014552:Urinary Tract Infections / Q000453:epidemiology / Q000382:microbiology* / Q000473:pathology / Q000503:physiopathology; D014556:Urine / Q000382:microbiology; D055815:Young Adult