No abstract

We identified 5 risk factors for nocardiosis after SOT. Low-dose cotrimoxazole was not found to prevent Nocardia infection. These findings may help improve management of transplant recipients.

SummaryMedically important yeasts of the genus Candida secrete aspartyl proteinases (Sap), which are of particular interest as virulence factors. Six closely related gene sequences, SAP1 to SAP6, for secreted proteinases are present in Candida albicans. The methylotrophic yeast Pichia pastoris was chosen as an expression system for preparing substantial amounts of each Sap isoenzyme. Interestingly, Sap4, Sap5 and Sap6, which have not yet been detected in C. albicans cultures in vitro, were produced as active recombinant enzymes. Different Sap polyclonal antibodies were raised in rabbits and tested before further application by enzyme-linked immunosorbent assay (ELISA) against each recombinant Sap. Two antisera recognized only Sap4 to Sap6. Using these antisera, together with sap null mutants obtained by targeted mutagenesis, we could demonstrate a high production of Sap4, Sap5 and Sap6 by C. albicans cells after phagocytosis by murine peritoneal macrophages. Furthermore, a ⌬sap4,5,6 null mutant was killed 53% more effectively after contact with macrophages than the wild-type strain. These results support a role for Sap4 to Sap6 in pathogenicity.

In patients with treatment-induced suppression of blood viral load the likelihood of having detectable HIV in semen is very low (< 4%). In addition, seminal shedding of cell-free and cell-associated HIV is significantly lower than in an untreated population of HIV-infected asymptomatic men. On a population basis, this effect of therapy may help to reduce sexual transmission of HIV. However, individual patients may still be infected as evidenced by continued shedding of cells harbouring the HIV provirus.

The prevalence, clinical presentation, and risk factors for hyperlactatemia among patients receiving antiretroviral therapy was determined during a 1-month period for patients in the Swiss HIV Cohort Study. Overall, 73 (8.3%) of 880 patients presented an increase in serum lactate of >1.1 times the upper normal limit (UNL). For 9 patients (1%), lactate elevation was moderate or severe (>2.2 times the UNL). Patients who presented with hyperlactatemia were more likely to be receiving stavudine with or without didanosine (odds ratio, 2.7; 95% confidence interval, 1.5-4.8), as compared with patients who received zidovudine-based regimens. The risk increased with increasing time receiving stavudine with or without didanosine. The association between hyperlactatemia and stavudine with or without didanosine was not biased by these medications being more recently available and, therefore, being given preferentially to patients who had prolonged use of nucleoside analog reverse-transcriptase inhibitors. Hyperlactatemia was associated with lipoatrophy, hyperlipidemia, and hyperglycemia. Age, sex, or stage of infection with human immunodeficiency virus were not predictive of hyperlactatemia. Determination of lactate levels may prove useful in the screening for mitochondrial toxicity.