Changing trends in prevalence, morbidity, and lethality in persistent diarrhea of infancy during the last decade in Mexico

Background. Persistent diarrhea (PD) of infancy has incurred high morbidity and lethality. However, decrease in its prevalence, morbidity, and lethality appeared to occur progressively throughout the last decade of the twentieth century. Our objective in this study was to compare prevalence, lethality, and morbidity of infants and children with PD managed in a pediatric referral hospital. Methods. We conducted a comparative cross-sectional study. A total of 546 patients with PD managed during three different periods (1988-1991, 1993-1994, and 1997-1999) were described and analyzed. Prevalence x 100 admissions, prevalence rates of nutritional status, sepsis, pneumatosis intestinalis, carbohydrate and protein intolerance, and lethality were calculated. We used Student t and x(2) tests (alpha = 0.05). Results. Mean age on admission was 13.8 +/- 24.3 months; 296 (54.2%) patients were males. Prevalence of admissions for PD decreased gradually from 31.7 to 13.8%; rates of lethality and mortality remained unchanged. Malnutrition had high prevalence throughout the three periods evaluated. Rate of carbohydrate intolerance diminished but protein intolerance increased; proportion of pneumatosis intestinalis and bowel perforation did not change. Isolation of Salmonella spp. and small bowel bacterial overgrowth decreased significantly from the 1988-1991 series when compared with later series. Conclusions. Although these observations were made at a pediatric referral hospital, they may suggest that prevalence of PD is diminishing. However, its lethality and mortality rates remain unchanged. Malnutrition persists as a relevant associated factor. Decrease of carbohydrate intolerance and increase in protein intolerance rates resemble rates of children with PD of developed countries. These observations may reflect an epidemiologic transition of PD in Mexico. (C) 2003 IMSS. Published by Elsevier Science Inc.