Effectiveness of antibiotics and antiseptics on coagulase-negative staphylococci for the decontamination of bone allografts.

Bone allografts retrieved from multi-organ donors can be decontaminated with minimally aggressive methods. Therefore, we evaluated the efficacy of antibiotics and antiseptics in the decontamination of bone fragments actively contaminated with coagulase-negative staphylococci. Gentamicin (512/1,024 microg/mL), rifampicin (400/1,000 microg/mL), chlorhexidine in alcohol and chlorhexidine soap were tested with different contact times and temperatures and a delay in starting decontamination. Gentamicin-susceptible strains dried on bone could be removed by gentamicin 512 microg/mL after 19 h of contact, while strains not dried on bone could be eliminated by soaking bone for 60 min in gentamicin 512 microg/mL. Rifampicin-susceptible strains could be eliminated by soaking bone for 60 min in rifampicin 1,000 microg/mL. In none of the experimental conditions could gentamicin/rifampicin-resistant staphylococci be eliminated. Antiseptics could not eliminate staphylococci from bone. Different antibiotics need different protocols in order to decontaminate bone allografts.

Granulomatous gastritis: a morphological and diagnostic approach.

The final diagnosis of granulomatous gastritis is based on morphological findings and clinical and laboratory data. Detailed analysis of the morphological features of the granulomas together with associated mucosal changes could generate more information on aetiology and pathogenesis. Biopsies from 71 patients diagnosed as having granulomatous gastritis were reviewed. Thirty-seven of these patients (52%) had Crohn's disease. In 18 patients (25%) an isolated granulomatous gastritis was diagnosed. In seven patients (10%) the final diagnosis was a foreign body reaction. Of the remaining cases, four (7%) corresponded to tumour-associated granulomas and one case each of sarcoidosis (1%), Whipple's disease (1%) and vasculitis-associated disease (1%). Two cases (3%) were unclassifiable. The granulomas were mainly found in the antrum (64% antrum only, 11% antrum and corpus, 6% transitional mucosa corpus-antrum). Granulomas were usually small. This was particularly true for those found in patients with Crohn's disease. Multiple granulomas were observed in the sarcoidosis, the Whipple's disease and vasculitis-associated cases. A pattern of chronic gastritis with atrophy was present in 95% of the biopsies (68/71 patients). Helicobacter pylori was detected in 92% of the biopsies (64/71 patients).

Whipple's disease: a histological, immunocytochemical, and electron microscopic study of the small intestinal epithelium.

At endoscopy, the duodenum in Whipple's disease frequently appears abnormal and some clinical features such as gastrointestinal blood loss and anaemia suggest epithelial damage. However, the intestinal epithelial cells themselves appear to be normal on light and electron microscopy. The aims of this study were to analyse in detail the cytological changes in epithelial cells over time and in response to therapy in biopsies obtained from 20 patients, to investigate the functional repercussion on digestive enzymes such as lactase, and to assess the expression by the epithelial cells of MHC antigens. Cytological changes were minimal at both the light- and the electron-microscopic level and MHC class I expression was preserved. However, changes indicative of functional deficits were demonstrated. Lactase and MHC class II expression were reduced or even absent. Antibiotic therapy resulted in normalization within 3-6 months. These findings are consistent with the clinical evolution and are of interest with regard to the importance of the immune response in aetiopathogenesis.

Detection of prostate specific antigen in pancreas and salivary glands: a potential impact on prostate cancer overestimation.

PURPOSE: We explored the immunohistochemical expression of prostate specific antigen (PSA) in pancreas and salivary glands. MATERIALS AND METHODS: We investigated 62 specimens from male and female subjects, representing normal cases and several pathological conditions of pancreas and salivary glands. Two commercially available monoclonal antisera for PSA and 1 for prostatic acid phosphatase were used. RESULTS: A consistently positive reaction for PSA and prostatic acid phosphatase, independent of patient sex, was noted in ductal cells of normal pancreas and normal salivary glands, as well as pleomorphic adenoma, adenocarcinoma and all oncocytic epithelial cells of Warthin's tumor. Reaction was absent in normal stromal and acinar cells, and squamous carcinoma. CONCLUSIONS: PSA is detectable in normal and cancer tissues far from the prostate. Therefore, we may not entirely rely on specificity of PSA alone to diagnose metastatic prostate cancer.

Gastric-type mucin and TFF-peptide expression in Barrett's oesophagus is disturbed during increased expression of MUC2.

AIMS: Barrett's oesophagus constitutes metaplastic epithelium, often diagnosed by mucin histochemistry. We determined the mucins and trefoil factor family (TFF)-peptides that were expressed in Barrett's oesophagus, in order to study changes in protein expression in early stages of Barrett's oesophagus development. METHODS AND RESULTS: Biopsy specimens of 71 Barrett's oesophagus patients were collected, and sections were stained for secretory mucins by histochemistry. Immunohistochemistry was performed for secretory mucins (MUC2, MUC5AC, MUC5B, MUC6), TFFs (TFF1, TFF2, TFF3), and proliferation (Ki67). Protein expression in the tissue was measured semiquantitatively. MUC5AC and TFF1 showed high levels and strong colocalization in the surface epithelium, whereas MUC6, MUC5B and TFF3 were found in the deeper glandular structures. TFF2 was found in both surface and glandular epithelium. The co-ordinate expression patterns of these six markers were similar to gastric antrum epithelium. MUC2 expression was ubiquitously associated with goblet cells within intestinal metaplasia, occurring in 68% of patients, and was correlated with increasing proliferation in the epithelium. CONCLUSIONS: Virtually all cells in Barrett's oesophagus epithelium displayed a secretory phenotype, demonstrating a co-ordinate gastric-type MUC and TFF expression. When MUC2 expression was more pronounced, the expression patterns of the other MUCs and the TFFs were increasingly disturbed. MUC2 expression may constitute a marker for early change in the phenotype of Barrett's oesophagus as a precancerous lesion.