Back to the Future: Penicillin-Susceptible Staphylococcus aureus.

Background: Widespread penicillin usage rapidly resulted in the emergence of penicillin resistance in Staphylococcus aureus. However, new data suggest that penicillin susceptibility may be in a period of renaissance. The objective of our study was to quantify penicillin resistance in methicillin-susceptible Staphylococcus aureus (MSSA) bacteremia.

Comparison of eight commercial enzyme immunoassays for the detection of Clostridium difficile from stool samples and effect of strain type.

We compared the performance of 8 Clostridium difficile enzyme immunoassays to cell cytotoxicity neutralization assay and toxigenic culture. The effect of strain type on assay performance was also examined. There were a total of 71 (14.

Epidemiology and antifungal susceptibility of bloodstream Candida isolates in Quebec: Report on 453 cases between 2003 and 2005.

Background: Between May 2003 and April 2005, a population-based surveillance of Candida bloodstream infections was conducted in Quebec. A total of 453 episodes of candidemia (464 yeast isolates) from 54 participating hospitals were studied.

Results: The annual incidence rate was three per 100,000 population.

Mycobacterium haemophilum epididymal abscess in a renal transplant patient.

Mycobacterium haemophilum is an established cause of cutaneous lesions in immunocompromised hosts. We report the first known case of epididymal abscess, which highlights the need to work up all specimens that are acid-fast bacillus-positive for M. haemophilum from immunocompromised hosts, regardless of body site.

A predominantly clonal multi-institutional outbreak of Clostridium difficile-associated diarrhea with high morbidity and mortality.

Background: In March 2003, several hospitals in Quebec, Canada, noted a marked increase in the incidence of Clostridium difficile-associated diarrhea.

Methods: In 2004 we conducted a prospective study at 12 Quebec hospitals to determine the incidence of nosocomial C. difficile-associated diarrhea and its complications and a case-control study to identify risk factors for the disease.

Virologic and immunologic response to a boosted double-protease inhibitor-based therapy in highly pretreated HIV-1-infected patients.

Purpose: To assess the virologic and immunologic response to a boosted double-protease inhibitor (PI) regimen of highly pretreated patients infected with HIV-1 and to examine the role of PI resistance and concentration of serum saquinavir.

Method: In an open-label prospective study, lopinavir/ritonavir, saquinavir-sgc, lamivudine, and other nucleoside analogues were offered to highly pretreated patients who had advanced HIV-1 infection and who had failed at least 2 previous highly active antiretroviral therapy regimens including at least 1 nonnucleoside reverse transcriptase inhibitor. The relationship between baseline drug resistance and steady-state saquinavir serum levels and early (week 4) and sustained (week 48) virologic response was documented.