Luzinete Alves Silva

Perfil etiológico das diarréias agudas de crianças atendidas em São Paulo

Objetivo: determinar o perfil etiologico das diarreias agudas de um grupo de criancas de baixo nivel socioeconomico atendidas em um servico regional de pronto-atendimento pediatrico. Metodo: durante dois anos, as criancas com diarreia aguda atendidas durante um horario pre-estabelecido do dia e da semana foram incluidas no estudo. Os outros criterios seletivos eram: a) idade inferior a 5 anos; b) nao utilizacao de antibiotico no mes precedente; c) ausencia de viagem para fora da cidade no mes precedente. Foram pesquisados nas fezes: a) rotavirus (imunofluorescencia e contra-imunoeletroforese); b) bacterias - cultura em agar MacConkey, agar SS, agar Columbia, verde brilhante, soroaglutinacao, deteccao de toxinas - INV, LT,ST,SLT I, SLT II, teste de Sereny, deteccao de fatores de virulencia -- EAF, eae ,BFP; c) protozoarios (Hoffman e Faust). No mesmo periodo, um grupo controle sem diarreia foi tambem avaliado para os mesmos patogenos fecais. Resultados: no periodo de marco de 1994 a junho de 1996, foram selecionadas para o estudo 154 criancas com diarreia aguda (GDA) e 42 criancas sem diarreia (GSDA). Foram detectados agentes enteropatogenicos em 112 casos (72,8%) do GDA, e em 9 (21,5%) do GSDA. A associacao de dois ou mais enteropatogenos ocorreu em 47 (30,5%) casos do GDA, e em 3 (7,1%) do GSDA. Os patogenos encontrados por caso, do GDA, foram: rotavirus 32 (20,8%), bacterias 53 (34,4%), ambos 25 (16,2%), e 2 (1,4%) com Giardia lamblia (em um caso associada a rotavirus e noutro a bacteria). No GSDA, foram detectadas bacterias em 8 casos (19,1%), e bacteria associada a Giardia lamblia em 1 (2,4%) caso. Das 105 bacterias isoladas no GDA, 90 eram Escherichia coli (EPEC 27, DAEC 24, ETEC 21, EAEC 18), 12 eram Shigella sp, 2 eram Salmonella sp, e uma era Yersinia sp. As criancas com infeccao mista - viral e bacteriana - apresentaram maior ocorrencia de vomitos repetidos, desidratacao e internacao.Conclusoes: as bacterias foram os enteropatogenos mais detectados nos casos de diarreia aguda, sendo a Escherichia coli a mais frequente. Na maior parte, as cepas de Escherichia coli eram de biovariedade nao-EPEC, habitualmente nao investigadas nos laboratorios de patologia clinica. O rotavirus foi encontrado em grande parcela dos casos, muitas vezes em associacao com as bacterias. Os protozoarios tiveram importância reduzida.

Etiologic profile of acute diarrhea in children in São Paulo

OBJECTIVE: To evaluate the etiologic profile of acute diarrhea in socioeconomically deprived children assisted at a regional pediatric emergency care service. METHODS: During two years all children with acute diarrhea assisted at a previously established day and week time schedule were included in the study. Other selective criteria were: a) age less than 5 years; b) nonuse of antibiotics in the previous month; and c) no travel outside the city in the previous month. Stool examination was used for the detection of the following microorganisms: a) rotavirus (immunofluorescence and counterimmunoelectrophoresis); b) bacteria - culture in MacConkey agar, SS agar, Columbia agar, bright green, serotyping, detection of toxins - INV, LT,ST,SLT I, SLT II, Sereny test, detection of virulence factors- EAF, eae, BFP; and c) protozoa (Hoffman and Faust). In the same period, a control group without diarrhea was also evaluated for the same fecal pathogens. RESULTS: Between March 1994 and June 1996, 154 children with acute diarrhea (AD) and 42 control children (WAD), that is, without acute diarrhea, were selected. In the AD group, intestinal pathogens were detected in 112 (72.8%) cases, and in 9 (21.5%) cases in the WAD group. The association of two or more intestinal pathogens occurred in 47 (30.5%) cases in the AD group, and in 3 (7.1%) cases in the WAD group. The pathogens identified in the AD cases were: Rotavirus: 32 (20.8%), bacteria: 53 (34.4%), both: 25 (16.2%), and 2 (1.4%) with Giardia lamblia (in one case associated with Rotavirus and in another one associated with bacteria). In the WAD group, only bacteria were detected in 8 (19.1%) cases, and bacteria associated with Giardia lamblia in 1 (2.4%) case. Altogether, there were 105 bacteria isolated in the AD group: 90 were Escherichia coli (EPEC 27, DAEC 24, ETEC 21, EAEC 18), 12 were Shigella sp, 2 were Salmonella sp, and one was Yersinia sp. Children with mixed infections (viral and bacterial) had increased incidence of severe vomiting, dehydration and hospitalization. CONCLUSIONS: Bacteria were the most frequent pathogens detected in acute diarrhea cases, among which Escherichia coli was highly predominant. The majority of Escherichia coli strains belong to non-EPEC varieties, strains that are not routinely evaluated in clinical laboratories of pathology. Rotavirus was found in a great number of diarrhea cases, often associated with bacteria. Protozoa showed reduced importance.

Diffusely Adhering Escherichia coli (DAEC) Strains of Fecal Origin Rarely Express F1845 Adhesin

A total of 398 diffusely adhering Escherichia coli (DAEC) strains of fecal origin were analyzed for the presence of sequences homologous to the structural subunit gene (daaE) of the F1845 fimbria. For that purpose, a DNA fragment homologous to daaE, obtained by PCR, was used as a probe in colony hybridization assays. Only two strains carried daaE and expressed F1845, suggesting that this fimbria is rare among DAEC strains.

Avaliação de desinfetantes químicos de uso doméstico contra Vibrio cholerae EL TOR (amostra não toxigênica)

The methodology of microbiological evaluation of disinfectants in permanently being questioned because the laboratorial protocols do not correspond to the real conditions under which these products are used. In 1985 the Use-Dilution method of AOAC was adopted in Brazil for microbiological qualification of chemical disinfectants for commercial purposes. Domestic disinfectants are tested in this way against Salmonella choleraesuis and Staphylococcus aureus ATCC strains, was chosen for this evaluation Vibrio cholerae in view of its current importance in Brazil, in terms of Public Health associated with the study of the disinfectants antimicrobial activities. Nineteen disinfectant products for domestic use for available to the public were evaluated microbiologically by means of simplified Use-Dilution test with 10 carriers. The active compounds of the products included formaldehyde, phenols, cresols, quaternary ammonium compounds, chlorine and ethanol. Seven were mixtures of these. According to the recommendations for their use, sixteen products should be used undiluted. Under these conditions, 9 disinfectants were vibriocides and 7 did not demonstrate this antibacterial activity. Four products in dilutions not clearly specified were also ineffective. The vibriocide products which must used without dilution were tested again, diluted at 1:2. These solutions did not inactivate V. cholerae showing that, microbiologically, their active compounds are used in limited concentrations. Commercial alcohol (95.5 degrees GL) at 1:3, chlorine 2.8% Agua sanitária at 1:200 and Lysoform at 1:20 came up to the standards required by the test.

Evaluation of the effect of chemical domestic disinfectants on Vibrio cholerae EL TOR (non toxigenic strain)

The methodology of microbiological evaluation of disinfectants in permanently being questioned because the laboratorial protocols do not correspond to the real conditions under which these products are used. In 1985 the Use-Dilution method of AOAC was adopted in Brazil for microbiological qualification of chemical disinfectants for commercial purposes. Domestic disinfectants are tested in this way against Salmonella choleraesuis and Staphylococcus aureus ATCC strains, was chosen for this evaluation Vibrio cholerae in view of its current importance in Brazil, in terms of Public Health associated with the study of the disinfectants antimicrobial activities. Nineteen disinfectant products for domestic use for available to the public were evaluated microbiologically by means of simplified Use-Dilution test with 10 carriers. The active compounds of the products included formaldehyde, phenols, cresols, quaternary ammonium compounds, chlorine and ethanol. Seven were mixtures of these. According to the recommendations for their use, sixteen products should be used undiluted. Under these conditions, 9 disinfectants were vibriocides and 7 did not demonstrate this antibacterial activity. Four products in dilutions not clearly specified were also ineffective. The vibriocide products which must used without dilution were tested again, diluted at 1:2. These solutions did not inactivate V. cholerae showing that, microbiologically, their active compounds are used in limited concentrations. Commercial alcohol (95.5 degrees GL) at 1:3, chlorine 2.8% Agua sanitária at 1:200 and Lysoform at 1:20 came up to the standards required by the test.

Evaluation of household chemical disinfectants for Vibrio cholerae EL TOR (non toxigenic strain)

The methodology of microbiological evaluation of disinfectants in permanently being questioned because the laboratorial protocols do not correspond to the real conditions under which these products are used. In 1985 the Use-Dilution method of AOAC was adopted in Brazil for microbiological qualification of chemical disinfectants for commercial purposes. Domestic disinfectants are tested in this way against Salmonella choleraesuis and Staphylococcus aureus ATCC strains, was chosen for this evaluation Vibrio cholerae in view of its current importance in Brazil, in terms of Public Health associated with the study of the disinfectants antimicrobial activities. Nineteen disinfectant products for domestic use for available to the public were evaluated microbiologically by means of simplified Use-Dilution test with 10 carriers. The active compounds of the products included formaldehyde, phenols, cresols, quaternary ammonium compounds, chlorine and ethanol. Seven were mixtures of these. According to the recommendations for their use, sixteen products should be used undiluted. Under these conditions, 9 disinfectants were vibriocides and 7 did not demonstrate this antibacterial activity. Four products in dilutions not clearly specified were also ineffective. The vibriocide products which must used without dilution were tested again, diluted at 1:2. These solutions did not inactivate V. cholerae showing that, microbiologically, their active compounds are used in limited concentrations. Commercial alcohol (95.5 degrees GL) at 1:3, chlorine 2.8% Agua sanitária at 1:200 and Lysoform at 1:20 came up to the standards required by the test.