Distribution study of Chlamydia trachomatis genotypes in symptomatic patients in Buenos Aires, Argentina: association between genotype E and neonatal conjunctivitis

BACKGROUND: Chlamydia trachomatis infections are the most prevalent sexually transmitted bacterial infections in the world. There is scarce data available referring to the distribution of C. trachomatis genotypes in Argentina. The aim of this study was to identify the genotypes of C. trachomatis circulating in the metropolitan area of Buenos Aires (Argentina) associated with ophthalmia neonatorum and genital infections. FINDINGS: From 2001 to 2006, 199 positive samples for C. trachomatis infection from symptomatic adult patients and neonates with ophthalmia neonatorum from two public hospitals were studied. C. trachomatis genotypes were determined by PCR-RFLP of an ompA fragment. Genotype E was the most prevalent regardless of the sample origin (46.3% 57/123 in adults and 72.4% 55/76 in neonates), followed by genotype D (19.5% 24/123) and F (14.6% 18/123) in adults, and G (9.2% 7/76) and D (7.9% 6/76) in neonates. We detected a significantly higher frequency of genotype E (p < 0.001, OR = 3.03 (1.57<OR<5.90)) in ophthalmia neonatorum than in genital specimens. Genotype D was associated with genital localization (p < 0.05, OR = 2.83 (1.03<OR<8.18)). CONCLUSION: We found a particularly increased frequency of C. trachomatis genotype E in neonatal conjunctivitis, which may indicate an epidemiological association between this genotype and the newborn population. The present study also contributed to increase the knowledge on genotype distribution of Chlamydia trachomatis in symptomatic adult patients in Buenos Aires, Argentina, in which genotypes E, D and F were the predominant ones.