Schwannomas, or neurinomas, are generally benign, slow-growing, asymptomatic neoplasms originating from the Schwann cells of a nerve sheath. As a part of spindle cell mesenchymal tumours, schwannomas arising from the gastrointestinal tract (GIT) are unusual; however, when they occur, the most common site involved is the stomach, which represents 0.2% of all gastric tumours. We report the case of a 35-year-old female patient with a history of pulmonary tuberculosis presenting with a large palpable abdominal mass reaching up to the peritoneal cavity. The initial clinical impression was a tuberculous abdominal mass, a cyst, or a teratoma. However, intra-operative findings during a subtotal gastrectomy revealed an exophytic gastric serosal mass, which suggested a gastrointestinal stromal tumour (GIST). Post-operative histopathological findings showed a fascicular arrangement of neoplastic spindle cells with pallisading nuclei that showed intense positivity for S-100 protein, and were negative for CD117 and desmin in immunohistochemistry studies. These results confirmed the final diagnosis of a gastric schwannoma.

OBJECTIVETo investigate the prevalence of kanamycin (kan) and ampicillin (amp) resistant bacteria in public drinking water.

METHODSBacteria containing kan and amp resistant genes were amplified by PCR and further characterized by colony hybridization and transformation studies. The genus of kan and amp resistant bacteria was determined with standard methods.

RESULTSAmong the 625 drinking water samples, 400 contained kan and amp resistant bacteria and the percentage was 42.5% and 57.5%, respectively, which was further confirmed by the amplification of a 810 bp kan resistant gene and a 850 bp amp resistant gene. Of the 170 kan resistant bacteria, 90 were Gram negative and 80 were Gram positive. Of the 230 amp resistant bacteria, 160 were Gram negative while 70 were Gram positive. Salmonella, Shigella, Staphylococcus, Streptococcus, and E.coli were detected as 13%, 11%, 17%, 30%, and 29%, respectively. Bacterial strain DH5alpha transformed with plasmids isolated from kan and amp resistant bacteria confirmed that the antibiotic resistant genes were mediated by plasmids.

CONCLUSIONDrinking water is contaminated with kan and amp resistant bacteria due to poor sanitary conditions.

Anti-Bacterial Agents ; pharmacology ; Bacteria ; drug effects ; isolation & purification ; Drug Resistance, Bacterial ; Pakistan ; Polymerase Chain Reaction ; Water Microbiology ; standards ; Water Supply ; standards