RESUMO
From prospective daily surveillance of diarrhea in a poor rural area of northeastern Brazil, this study of prolonged diarrheal episodes identified the 3% of diarrheal episodes that lasted 15 days or longer. These episodes also defined a subpopulation of children who spent over 16% of their days with diarrhea. Such children warrant further attention in an attempt to define potentially treatable causes as well as to assure appropriate nutritional support. There was no single season for these prolonged illnesses, but they appeared to involve both the wet, slightly warmer season of peak enterotoxigenic Escherichia coli diarrhea as well as the dry, slightly cooler season of peak rotaviral infections. Limited etiologic data support this idea that multiple pathogens are found, often in combination with each other, that may work together to contribute to the important problem of chronic diarrhea. Future studies should focus attention on further defining risk factors, mechanisms, and appropriate therapy for the subset of children who experience prolonged diarrhea in this type of setting.
Assuntos
Diarreia/epidemiologia , Brasil , Pré-Escolar , Diarreia/etiologia , Fezes/microbiologia , Fezes/parasitologia , Feminino , Humanos , Lactente , Masculino , Estudos Prospectivos , Recidiva , Estações do Ano , Fatores de TempoRESUMO
In contrast to prior experience in this setting, three of four Shigella flexneri strains recently isolated from patients in Northeastern Brazil with acute inflammatory diarrhea were found to be resistant to sulfamethoxazole, trimethoprim and the combination in vitro. We performed mating studies to determine if the resistance was transferable, and then isolated and characterized plasmid DNA from the resistant Shigella isolates, other resistant Enterobacteriaceae isolated simultaneously from the stools of these individuals, and transconjugant strains. Each of the resistant Shigella strains contained a large plasmid. These plasmids were of different molecular weights ranging from 30 to 50 Mdal in size. Two of these plasmids were transferred with sulfamethoxazole-trimethoprim resistance to E. coli K-12 recipient strains. These findings of transferable resistance to sulfamethoxazole-trimethoprim associated with plasmids in Shigella and in other Enterobacteriaceae raises concerns about the potential limitations of this widely used antimicrobial combination.
Assuntos
Shigella flexneri/efeitos dos fármacos , Sulfametoxazol/farmacologia , Trimetoprima/farmacologia , DNA Bacteriano/isolamento & purificação , Diarreia/microbiologia , Combinação de Medicamentos/farmacologia , Resistência Microbiana a Medicamentos , Eletroforese em Gel de Ágar , Humanos , Técnicas In Vitro , Testes de Sensibilidade Microbiana , Plasmídeos/efeitos dos fármacos , Shigella flexneri/isolamento & purificação , Combinação Trimetoprima e SulfametoxazolRESUMO
In contrast to prior experience in northeastern Brazil, three of four Shigella flexneri strains recently isolated from patients with acute inflammatory diarrhea in this setting were found to be resistant to sulfamethoxazole-trimethoprim. The resistant strains contained large, different plasmids, two of which were transferred with sulfamethoxazole-trimethoprim resistance to Escherichia coli K-12 recipient strains.
Assuntos
Antidiarreicos/farmacologia , Shigella flexneri/efeitos dos fármacos , Sulfametoxazol/farmacologia , Trimetoprima/farmacologia , Antibacterianos/farmacologia , Brasil , DNA Bacteriano/análise , Resistência Microbiana a Medicamentos , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , PlasmídeosRESUMO
Diarrhea is a leading cause of death in tropical countries. One of the highest childhood mortalities is in northeastern Brazil, where little is known about the morbidity, etiology, and risk factors of diarrhea. Prospective village surveillance over 30 months revealed diarrhea attack rates of more than seven episodes per child-year at six to 11 months of age among the children of the poorest families. Other risk factors included early weaning and the lack of toilets. Diarrhea led to weight loss and stunted growth. Enterotoxigenic Escherichia coli and rotaviruses were the most common pathogens, accounting for 21% and 19% of cases, respectively, followed by Shigella species (8.0%), Campylobacter jejuni (7.5%), Giardia species (6.7%), Strongyloides species (5.3%), and enteropathogenic E coli serotypes (4.6%). Most (84%) enterotoxigenic E coli were isolated during the rainy season of October to March (P less than 0.03), whereas 71% of rotaviral illnesses occurred during the drier months of June to October (P less than 0.03). In the present study, the early occurrence and nutritional impact of diarrhea and weaning, as well as the major etiologic agents of diarrhea and their different seasonal patterns have been defined for this region in which life-threatening diarrhea is endemic.