Colovaginal and colovesical fistulae: the diagnostic paradigm.

BACKGROUND: Colovaginal and colovesical fistulae (CVF) are relatively uncommon conditions, most frequently resulting from diverticular disease or colorectal cancer. A high suspicion of a CVF can usually be obtained from an accurate clinical history. Demonstrating CVF radiologically is often challenging, and patients frequently undergo a multitude of investigations prior to definitive management. The aim of this study was to develop an algorithm for the investigation of suspected CVF in order to improve diagnosis and subsequent management. METHODS: Thirty-seven patients from a single NHS Trust with a diagnosis of colovaginal or colovesical fistula were included in the study. Clinical records and imaging were reviewed retrospectively, and data on demographics, symptoms, investigations, management and outcome were collated. RESULTS: A total of 87.5% patients with a colovesical fistula presented with pathognomic symptoms of faecaluria or pneumaturia. The commonest aetiologies were diverticular disease (72.9%), colonic and gynaecological neoplasia (10.8% each). Computerised tomography (CT) was the most frequently performed investigation (91.9%) and was most sensitive in detecting the fistula (76.5%) and underlying aetiology (94.1%). Colonoscopy was most sensitive in detecting an underlying colonic malignancy (100%). Resectional surgery was performed in 62.1% of cases, although morbidity and 1-year mortality was significant, with rates of 21.7 and 17.4%, respectively. CONCLUSIONS: The diagnosis of CVF is predominately a clinical one, and patients with a suspected CVF are over-investigated. Investigations should be focused on determining aetiology rather than demonstrating the fistulous tract itself. We propose that, in the majority of cases, CT and lower gastrointestinal endoscopy should suffice.

Stability of vancomycin in plastic syringes measured by high-performance liquid chromatography.

The shelf-life of vancomycin in infusion fluids was studied using high-performance liquid chromatographic (HPLC) methods. Vancomycin was stable (loss in potency less than 10%) for 47 days and 29 days, respectively, when dissolved in water-for-injections BP at 25 degrees C and stored in plastic syringes (Becton Dickinson Plastipak (three-piece) and B. Braun Medical Injekt (two-piece)). In sodium chloride solution (0.9%; pH 5.4) it was stable for 62 and 34 days, while in dextrose solution (5%; pH 4.2) it was stable for 55 and 33 days, respectively, at the same temperature. At 4 degrees C vancomycin was stable in all three infusion fluids and both types of syringe for at least 84 days.

Changes in electrophoretic mobility and lytic enzyme activity associated with development of flocculating ability in Saccharomyces cerevisiae.

Cells from stationary-phase cultures of two strains of Saccharomyces cerevisiae (3 and 20) failed to flocculate when grown in a complex or a chemically defined medium, while those of two other strains (11 and 13) flocculated when grown in either medium. Strain 30 flocculated when grown in complex but not defined medium and harvested from stationary-phase cultures. pH-electrophoretic mobility measurements on all five strains showed that mobility attributable to carboxyl groups usually increased as cultures progressed from the exponential to the stationary phase, while that caused by phosphate groups tended to decline. Acquisition of flocculating ability was accompanied in strains 11 and 30 by a slight increase in amidase activity, and greater increases compared with nonflocculent populations in activities of leucine aminopeptidase. alpha-mannosidase, and proteinase C. Activities of proteinases A and B showed no correlation with acquisition of flocculating ability.