Pathology
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Histoplasma capsulatum is a pathogenic fungus endemic to North, Central, and South America. Histoplasmosis is primarily acquired by inhalation and in immunocompetent hosts infection is generally limited to the lungs. Histoplasmosis may disseminate systemically in hosts with defective cell-mediated immunity or massive inoculation. ⋯ The ovarian histoplasmosis was discovered incidentally at surgery for a persistent colo-cecal fistula, which had developed 6 months earlier and was originally associated with an Actinomyces and Fusobacterium pelvic abscess. The patient had no evidence of active pulmonary histoplasmosis and her disseminated histoplasmosis likely resulted from re-activation of latent disease. This is the first description of disseminated histoplasmosis presenting as ovarian dysfunction in a patient with SLE.
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Ten neuroendocrine tumors (NET) in the liver are presented, in which the diagnosis was made on fine needle aspiration cytology and cell blocks from the aspirate. In seven of the patients with liver metastasis, a biopsy-proven extrahepatic primary NET had been previously diagnosed, while in three patients no extrahepatic neoplasm could be identified, suggesting that the NET may have been a primary in the liver. Based on cytomorphological findings the cases were typed as either round cell type, spindle cell type or polygonal cell type. In all cases, immunopositivity for neuroendocrine markers provided reliable evidence of the cell of origin and distinguished them from well-differentiated hepatocellular carcinoma, adenocarcinomas and other neoplasms, which sometimes may present a diagnostic dilemma.
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Control of tuberculosis, the single largest killer among the infectious diseases, has been threatened by the emergence of multidrug-resistant Mycobacterium tuberculosis (MDRTB) infection due to the limited treatment options. Rifampicin (RIF) resistance is considered as a marker for MDRTB. The aim of this study was the detection of rpoB gene mutations and rifabutin resistance in MDRTB strains recently isolated in Australia by a line probe assay (INNO-LiPA Rif. ⋯ Of the RIF-resistant MDRTB strains, 18% appeared to be rifabutin-sensitive and produced delta S2 and delta S3 INNO-LiPA patterns. We conclude that amino acid substitutions at Asp516 and Ser522 in the rpoB gene in RIF-resistant M. tuberculosis predict rifabutin susceptibility for MDRTB. Use of the LiPA for RIF and rifabutin resistance may facilitate the rapid response required to limit the extent and severity of MDRTB transmission and infection.