Prospective Cohort Study of Enterotoxigenic Escherichia coli Infections in Argentinean Children

• Autores: Viboud, Gloria I.; Jouve, Mabel J.; Binsztein, Norma; Vergara, Marta; Rivas, Marta; Quiroga, Marina; Svennerholm, Ann-Mari
• Año de publicación: 1999
• Idioma: inglés
• Tipo de recurso: artículo
• Fuente: Journal of Clinical Microbiology 1999; 37(9): 2829–2833.
• Materia: Infecciones por Escherichia coli; Estudios de Cohortes; Lactante; Argentina; Escherichia coli
• Institución: Administración Nacional de Laboratorios e Institutos de Salud "Dr. Carlos G. Malbrán"

Fil: Viboud, Gloria I. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Bacteriología; Argentina.
Fil: Jouve, Mabel J. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Bacteriología; Argentina.
Fil: Binsztein, Norma. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Bacteriología; Argentina.
Fil: Vergara, Marta. Universidad Nacional de Misiones. Cátedra de Bacteriología; Argentina.
Fil: Rivas, Marta. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Bacteriología; Argentina.
Fil: Quiroga, Marina. Universidad Nacional de Misiones. Cátedra de Bacteriología; Argentina.
Fil: Svennerholm, Ann-Mari. University of Göteborg. Department of Medical Microbiology and Immunology; Suiza.
In a follow-up study, enterotoxigenic Escherichia coli (ETEC) infections in 145 children from two communities located in northeastern Argentina were monitored for 2 years. The occurrence of diarrhea was monitored by weekly household visits. Of 730 fecal specimens collected, 137 (19%) corresponded to diarrheal episodes. ETEC was isolated from a significantly higher proportion of symptomatic (18.3%) than asymptomatic (13.3%) children (P 5 0.04541). Individuals of up to 24 months of age were found to have a higher risk of developing ETEC diarrhea than older children (odds ratio [OR], 3.872; P 5 0.00021). When the toxin profiles were considered, only heat stable enterotoxin (ST)-producing ETEC was directly associated with diarrhea (P 5 0.00035). Fifty-five percent of the ETEC isolated from symptomatic children and 19% of the ETEC isolated from asymptomatic children expressed one of the colonization factors (CFs) investigated, i.e., CF antigen I (CFA/I), CFA/II, CFA/III, and CFA/IV; coli surface antigens CS7 and CS17; and putative CFs PCFO159, PCFO166, and PCFO20, indicating a clear association between diarrhea and ETEC strains that carry these factors (P 5 0.0000034). The most frequently identified CFs were CFA/IV (16%), CFA/I (10%), and CS17 (9%). CFs were mostly associated with ETEC strains that produce ST and both heat-labile enterotoxin and ST. Logistic regression analysis, applied to remove confounding effects, revealed that the expression of CFs was associated with illness independently of the toxin type (OR, 4.81; P 5 0.0003). When each CF was considered separately, CS17 was the only factor independently associated with illness (OR, 16.6; P 5 0.0151). Most CFs (the exception was CFA/IV) fell within a limited array of serotypes, while the CF-negative isolates belonged to many different O:H types. These results demonstrate that some CFs are risk factors for the development of ETEC diarrhea.