Proteus spp. as Putative Gastrointestinal Pathogens.

Proteus species, members of the Enterobacteriaceae family, are usually considered commensals in the gut and are most commonly recognized clinically as a cause of urinary tract infections. However, the recent identification of Proteus spp. as potential pathogens in Crohn's disease recurrence after intestinal resection serves as a stimulus to examine their potential role as gut pathogens. Proteus species possess many virulence factors potentially relevant to gastrointestinal pathogenicity, including motility; adherence; the production of urease, hemolysins, and IgA proteases; and the ability to acquire antibiotic resistance. Gastrointestinal conditions that have been linked to Proteus include gastroenteritis (spontaneous and foodborne), nosocomial infections, appendicitis, colonization of devices such as nasogastric tubes, and Crohn's disease. The association of Proteus species with Crohn's disease was particularly strong. Proteus species are low-abundance commensals of the human gut that harbor significant pathogenic potential; further investigation is needed.

The association between ethnicity and vaginal microbiota composition in Amsterdam, the Netherlands.

OBJECTIVE: To evaluate whether ethnicity is independently associated with vaginal microbiota (VMB) composition in women living in Amsterdam, the Netherlands, as has been shown for American women. METHODS: Women (18-34 years, non-pregnant, N = 610) representing the six largest ethnic groups (Dutch, African Surinamese, South-Asian Surinamese, Turkish, Moroccan, and Ghanaian) were sampled from the population-based HELIUS study. Sampling was performed irrespective of health status or healthcare seeking behavior. DNA was extracted from self-sampled vaginal swabs and sequenced by Illumina MiSeq (16S rRNA gene V3-V4 region). RESULTS: The overall prevalence of VMBs not dominated by lactobacilli was 38.5%: 32.2% had a VMB resembling bacterial vaginosis and another 6.2% had a VMB dominated by Bifidobacteriaceae (not including Gardnerella vaginalis), Corynebacterium, or pathobionts (streptococci, staphylococci, Proteus or Enterobacteriaceae). The most prevalent VMB in ethnically Dutch women was a Lactobacillus crispatus-dominated VMB, in African Surinamese and Ghanaian women a polybacterial G. vaginalis-containing VMB, and in the other ethnic groups a L. iners-dominated VMB. After adjustment for sociodemographic, behavioral and clinical factors, African Surinamese ethnicity (adjusted odds ratio (aOR) 5.1, 95% confidence interval (CI) 2.1-12.0) and Ghanaian ethnicity (aOR 4.8, 95% CI 1.8-12.6) were associated with having a polybacterial G. vaginalis-containing VMB, and African Surinamese ethnicity with a L. iners-dominated VMB (aOR 2.8, 95% CI 1.2-6.2). Shorter steady relationship duration, inconsistent condom use with casual partners, and not using hormonal contraception were also associated with having a polybacterial G. vaginalis-containing VMB, but human papillomavirus infection was not. Other sexually transmitted infections were uncommon. CONCLUSIONS: The overall prevalence of having a VMB not dominated by lactobacilli in this population-based cohort of women aged 18-34 years in Amsterdam was high (38.5%), and women of sub-Saharan African descent were significantly more likely to have a polybacterial G. vaginalis-containing VMB than Dutch women independent of modifiable behaviors.

Quantitative bacterial micro-assay for rapid detection of serum phenylalanine on dry blood-spots: application in phenylketonuria screening.

Phenylketonuria is an inherited metabolic disease, which is characterized by an increased level of serum phenylalanine. Quantitative measurement of phenylalanine in the serum of phenylketonuria patients is necessary to confirm the disease, and to distinguish phenylketonuria from other forms of hyperphenylalaninemia. In this study, we report a rapid and inexpensive micro-assay for simultaneous detection and quantitative measurement of serum phenylalanine on dry blood-spots. Analysis of the standard curve showed a broad linear range for phenylalanine from 120 to 1800 micromol/L. Application of this method, the standard Guthrie bacterial inhibition assay and a high-performance liquid chromatography (HPLC) method for analysis of 34 samples from phenylketonuria patients and control samples produced comparable results, with the regression equation Y = 0.994X + 0.996. The advantage of this method over the Guthrie bacterial inhibition assay is its ability to measure serum phenylalanine quantitatively without false positive results. The method was successfully applied to dried blood-spots, serum and whole blood. The cost per sample is approximately 20-50 US cents, which is much less than for HPLC and commercial enzyme kits. The method can be automated, and is thus suitable for neonatal and mass screening for phenylketonuria, especially in developing countries where funding is a limiting factor.

[The effect of selective bowel decontamination and mechanical bowel preparation on bacterial translocation due to intraabdominal hypertension]. / Kariniçi hipertansiyon modelinde gelisen bakteriyel translokasyon üzerine selektif bagirsak dekontaminasyon ve mekanik bagirsak temizliginin etkileri.

BACKGROUND: The objective of our study is to evaluate the preventive effects of selective digestive decontamination (SDD) and mechanical bowel preparation in rats with experimentally induced bacterial translocation. METHODS: Fourty adult male Sprague Dowley rats weighing 250-300 g. were divided equally into four groups as Group 1 (sham [control]), Group 2 (experimentally induced IAH at 19 mmHg), Group 3 ( SDD group) and Group 4 (SDD and mechanical bowel preparation with 19 mmHg intraabdominal pressure). Group 3 and 4 were treated at 12 hours intervals with oral gentamycine 5 mg/kg and IM sefotaxime 100mg/kg Mechanical bowel preparation was performed by oral administration of sodium phosphate. After 24 hours all rats were sacrified; mesenteric lymph nodes, spleen and liver biopsy specimens were harvested aseptically. Specimens were diluted and cultured in McConkey medium and the colony-forming units (CFU/gr ) were calculated. RESULTS: In Kruskal Wallis tests there were no significant differences between Group 1 and 3 or 4, and also Group 3 and 4 (p>0.05, p=0.872 respectively), while differences between Group 1 and 2, and also Group 3 and 4 were statistically significant (p<0.001) with respect to CFU/g estimates. CONCLUSION: These data indicate that selective intestinal decontamination and mechanical bowel preparation prevent bacterial translocation due to intraabdominal hypertension.

Adhesive properties of Proteus genus related to antimicrobial agents resistance.

The in vitro attachment of 49 Proteus spp. to human urinary tract epithelial cells was determined. The antibacterial spectrum to all species of the Proteus isolates from hospitalized patients was measured against the most common antibiotics (Amikacin, Cefamandole, Cefoxitin, Ceftriaxone, Cephalothin, Kanamycin, Nalidixic acid, Oxolinic acid, Pipemidic acid, Piromidic acid, Tobramycin). 18 of them were multiresistant and the other 31 expressed susceptibility to the above antibiotics. Bacterial adherence to uroepithelial cells was studied in relation to susceptibility on antibiotics. The mean of bacteria per cell for the 31 strains grouped as susceptible was 20.2 and for the 18 strains grouped as resistant the mean was 55.1. Our results demonstrate a significant relationship between bacterial adhesion and antibiotic susceptibility pattern by Student's t test (P less than 0.01).

Adhesion of Proteus species to various cell types.

Pathogenic and saprophytic Proteus strains from the urine of patients with urinary tract infections and healthy adults respectively were evaluated with regard to their ability to adhere in vitro to homologous cells (uroepithelial cells from urinary sediment and cultured WISH cells) and heterologous cells (RK-13 and MDCK cells). The effect on attachment of pretreating bacteria with subinhibitory concentrations of piperacillin and sagamicin was also determined for one sensitive and one resistant strain. Fifty percent of the pathogenic Proteus strains demonstrated good adherence to human urinary epithelial cells, whereas saprophytic strains did not adhere. There was a lower rate of attachment to culture cells. Piperacillin and sagamicin in subinhibitory concentrations caused a decrease in the attachment of the sensitive Proteus strain.