Revista de igiena, bacteriologie, virusologie, parazitologie, epidemiologie, pneumoftiziologie. Bacteriologia, virusologia, parazitologia, epidemiologia最新文献

The authors describe the evidencing of the O157H7 E. coli serotype--an enterohaemorrhagic strain of E. coli--for the first time in our country. This germ is incriminated in haemorrhagic enteritis of children and adults, accompanied or not by an uremic haemolytic syndrome. A total of 717 strains were investigated, obtained from cases of haemorrhagic enteritis (283), nonhemorrhagic enteritis (174), food poisoning (27), and a control lot of subjects without signs of enteritis (233). Identification of the strains was done with a screening method (McConkey) with D-sorbitol in place of lactose, and with anti-O157, and anti-H7 sera. The results obtained have indicated a total of 37 positive strains in haemorrhagic enteritis (69.8%), 12 strains in nonhemorrhagic enteritis (22.65%), and 4 strains in food poisoning (7.55%). No strain was isolated from the control group. The percentage of isolated O157H7 E. coli strains in our county is of 7.55% and this contributes to additional knowledge in the definition of the still unknown etiology of diarrhoeic disease in our country.

Enterotoxin-producing Klebsiella pneumoniae was implicated in the induction of intrahospital infections in new-born babies. A total of 46 children and 4 adults (hospital personnel) were involved. Most of the subjects (82.6%) had median and light forms of gastroenterocolitis, and recovered following biological re-equilibration. In 17.39% of the cases the evolution was more severe due to advanced dehydration and secondary dissemination of the infection. Two children (approximately 4%) died. Factors that favored the dissemination of the infection were hygiene deficiencies and ignorance of functioning rules of materno-infantile units, and these included: admission to the hospital of working personnel with acute phenomena of enterocolitis; administration of sweetened solutions that were prepared without control and stored at room temperature; the "critical" point represented by the special room for "the accommodation" of the newborns, a "key-point" where infection was disseminated to other wards following dispersion of "adapted babies".

With a view to optimize the etiological diagnosis of diarrhoea the authors have attempted to improve the diagnostic methodology for the parasite Cryptosporidium spp. as a current general technique, as well as a screening technique. A comparative evaluation of the various methods used for the concentration and the staining of cysts of Cryptosporidium spp. was done after quantification according to a five parameter score: electiveness, morphology, chromatic contrast, rapidity and accessibility. The importance of the screening tests in the diagnosis of cryptosporidiosis was evaluated according to indicators such as sensitivity, specificity and predictive value. The maximal general score (17) was obtained with the modified Ziehl-Neelsen stain which was both sensitive and viable, and was used as a method for the confirmation of the presence of the parasite. With regard to the screening methods rapid techniques employing methylene-blue and/or fuchsine gave indicator values between 76% and 83%. The best results were obtained when samples were enriched with the aid of concentration techniques. It is appreciated that the concomitant and repeated use of two techniques of diagnosis, a rapid one and a confirmation technique aimed at demonstrating the presence of Cryptosporidium cysts allows a competent parasitological diagnosis of cryptosporidiosis.

The efficiency was studied, in experimental and practical conditions, of media for the isolation of C. pylori, as well as criteria for diagnosis and identification. The highest sensitivity was obtained with Columbia gelose, and a lower sensitivity was achieved with Campy I. C. gelose, and with heart-brain gelose, prepared as chocolate gelose, and Columbia gelose with integral blood. Both variants of the Mueller-Hinton gelose, even in the chocolate formula, gave negative results. Of the fluid media, supplemented with blood or with serum, only broth for I. C. blood cultures, and the heart-brain broth permitted the development of small cultures, while the soya-tripticase broth and the Mueller-Hinton broth remained sterile. None of the media, either solid or fluid, as such or supplemented with factors X, V, or X + V, did allow the development of C. pylori. In natural conditions, by inoculating 92 samples of gastric mucosa from patients with gastritis, with or without ulcers, confirmed histologically on Columbia chocolate gelose as such, or in a selective variant, 50 positive results were obtained with both variants, 9 positive results on the selective variant, and one positive result on the nonselective variant. The direct microscopic examination of samples from the mucosa disclosed the presence of C. pylori in all 60 samples that had also been confirmed by culture, as well as in another 21 samples from a total of 32 samples with negative cultures (88%). The direct urease test performed directly from the sample was done in 90 cases and was positive in 64 out of 79 samples that had been confirmed bacteriologically (77.2%), but in none of the 11 negative samples. The positive prediction index is thus of 100%, and the negative index is of 37.9%. Procedures for identification consisted in a definition of morphological characteristics, and in the cultivation, and biochemical features (including catalase and oxydase determination), which can define the Campylobacter genus, and the urease test, the sensitivity to cephalotine and the resistance to nalidixic acid for the differential species diagnosis. In conclusion cultivation of C. pylori presumes the use of media with superior quality peptones, supplemented with blood lactate in the gelose chocolate formula. The direct urease test is very useful as a procedure for diagnosis, and this can be done in the departments of gastroenterology.