Yoghurt: an unlikely source of Campylobacter jejuni/coli.

Knowledge of the relative insensitivity of Campylobacter jejuni to moderately acid environments prompted us to study its survival in different batches of yoghurt of pH range 4.2-5.3 and the role of organic or inorganic acid in the die-off of this pathogen. None of the 11 strains of C. jejuni or C. coli survived more than 25 min in yoghurt. Suspecting that this rapid die-off cannot be accounted for by the pH of the yoghurt we compared the survival rates of C. jejuni in milk, whose pH had been adjusted by lactic, propionic and hydrochloric acid respectively, with that of yoghurt. Even for an inoculum of 10(5)-10(8) cfu/ml propionic acid was bactericidal in minutes. Lactic acid reduced the bacterial populations by 3-5 logs in 30 min. Strong inorganic acid HCl, by contrast, had little or no effect on the populations. Although lactic acid is quite bactericidal for C. jejuni, it is apparently not the only factor to which the prompt elimination of this pathogen from yoghurt could be attributed.

Disseminated hereditary gastrointestinal polyposis with orocutaneous hamartomatosis (Cowden's disease).

Cowden's disease, first described by Lloyd and Dennis in 1962, is a rare disseminated polyposis of the gastrointestinal tract with an autosomal dominant inheritance pattern, infrequently cited in the contemporary gastroenterological literature. In addition to multiple polyps, which are scattered throughout the gastrointestinal tract from the mouth to the anus, orocutaneous hamartomas and frequent benign and malignant cutaneous, thyroid and breast tumors are thought to represent the most common manifestations of the disease. Ectodermal lesions are most frequently reported as a salient feature, and represent the most consistent element in the definition of this condition in the majority of cases, most of which are recorded in the dermatological literature (multiple hamartoma syndrome or Cowden's disease). This article presents four cases of Cowden's disease, the patients being members of two genetically unrelated families. All four patients had disseminated polyposis of the gastrointestinal tract, extending from the oral mucosa to the anus, while the cutaneous lesions and the concomitant tumors were present either in a fully developed or only rudimentary form, or were even absent. The authors propose that the term "disseminated hereditary gastrointestinal polyposis with orocutaneous hamartomatosis " be introduced and consistently used in the gastroenterological literature when referring to Cowden's disease, which seems more common than previous reports in the literature would indicate.

Some biological characteristics of Escherichia coli strains isolated from acute diarrhoeal diseases of infants.

The aim of this study was to evaluate the methods of biological characterization of Escherichia coli strains, in order to use them as screening tests in clinical microbiological laboratories. In two thirds of the 45 E. coli, isolated from acute intestinal infection of infants, different factors of virulence were found. The strains showed prevalently an enterotoxigenic character (66,6%), which was in correlation with the increased permeability (62,2%). Adhesive properties were present in 20% of E. coli independent of their enterotoxigenicity; only 11,1% of the strains had penetrating abilities. The rabbit skin model seems to be accurate and quick for ETEC screening purposes, as is the guinea-pig eye for the EIEC. The mouse intestinal loop has been found sensitive but time-consuming. The infant mouse model is simple and quick, but in this study it has not given optimal results. The Vero cell culture system is simple and easy to perform, but at least for some strains the preparations should be concentrated. The investigation of adhesiveness by haemagglutination is possible to conduct in every small clinical laboratory. Our opinion is, however, that after the isolation of E. coli from different pathological materials, the determination of the antigenic structure of the strains is necessary and later on the additional biological characterization should be performed.

Xylose lysine deoxycholate agar for the isolation of Salmonella and Shigella from clinical specimens.

Xylose lysine deoxycholate (XLD) agar was more efficient for the detection of Shigella sonnei than Salmonella-Shigella (SS) agar and Drigalski agar, XLD was slightly more efficient for the detection of Salmonellae by direct plating than SS agar. Xylose lysine deoxycholate agar is proposed as the second selective plating medium for Shigellae isolation. It is also a useful second selecting plating medium for the isolation of Salmonellae serotypes, which form non-characteristic colonies on Bismuth-Sulfite agar. Efficiency comparisons between 4 direct plating media and one enrichment medium were made during the period of 3 years by analysing 21793 fresh clinical stool specimens. In that time 1394 Salmonella and 519 Shigella strains were isolated.

Septicaemia and meningitis with campylobacter fetus subspecies intestinalis.

Two cases of infection with Campylobacter fetus subspecies intestinalis are reported. In a 46-year-old farmer the development of septicaemic campylobacteriosis with acute gastroenterocolitis was favoured by malnutrition due to chronic alcoholism. After treatment with erythromycin the patient recovered completely. The second patient, a 40-year-old worker with meningitis, recovered after combined streptomycin-erytro-mycin therapy. In both patients antibodies against homologous and reference strains of Campylobycter fetus subspecies intestinalis, serotype 1 (Mitscherlich) were demonstrated in titres ranging from 1:16 to 1:64 by type the complement-fixation test.