The results of the present study suggest that ASA score ≤ 2 and use of rifampin-combination therapy are two independent factors associated with favorable outcome of patients treated for total hip or knee prosthetic infections due to S. aureus.

A 5 nuclease PCR assay for detection of the Yersinia pestis plasminogen activator (pla) gene in human respiratory specimens with simulated Y. pestis infection was developed. An internal positive control was added to the reaction mixture in order to detect the presence of PCR inhibitors that are often found in biological samples. The assay was 100% specific for Y. pestis. In the absence of inhibitors, a sensitivity of 10 2 CFU/ml of respiratory fluid was obtained. When inhibitors were present, detection of Y. pestis DNA required a longer sample treatment time and an initial concentration of bacteria of at least 10 4 CFU/ml. The test's total turnaround time was less than 5 h. The assay described here is well suited to the rapid diagnosis of pneumonic plague, the form of plague most likely to result from a bioterrorist attack.Protecting the population against an act of bioterrorism is a major concern for many governments. Yersinia pestis, the agent of plague, can be viewed as a potential bioweapon due to its ability to cause high rates of morbidity and mortality in humans. The intentional dissemination of plague by terrorists would most likely occur by aerosolization, causing fulminant pneumonia in exposed individuals. Since pneumonic plague is almost always fatal when untreated, clinical microbiology laboratories play a pivotal role in the early detection of this type of infectious agent, thus allowing rapid implementation of effective preventive measures. Availability of a rapid diagnostic procedure using molecular techniques (such as real-time PCR) is essential in the establishment of coordinated laboratory response systems. Several PCR assays have been developed (1, 3-7, 10, 13): the plasmidic plasminogen activator (pla) gene (located on the Y. pestis-specific pPst/pCP1 plasmid [5,11]) was found to be the most sensitive target, since its copy number can be as high as 186 per bacterium (8). In the present study, we describe a real-time PCR protocol for detection of the Y. pestis pla gene. The assay is based on 5Ј exonuclease assay technology coupled with automated DNA extraction and uses a minor groove binder-conjugated small DNA probe for DNA detection via hybridization-triggered fluorescence: subsequent multiplex development can be thus envisaged. Inclusion of an internal positive control (IPC) in each batch assay enabled the detection of endogenous PCR inhibitors.The primers and the fluorogenic probe for the pla gene (GenBank accession no. M27820) were designed with Primer Express software, version 2.0 (Applied Biosystems, Foster City, Calif.) and were obtained from Applied Biosystems (Warrington, United Kingdom). The nucleotide sequences of the forward and reverse primers were 5Ј-GAAAGGAGTGCGG GTAATAGGTT-3Ј (positions 816 to 838) and 5Ј-AACCAGC GCTTTTCTA-3Ј (positions 869 to 884), respectively. The sequence of the minor groove binder probe was 6-carboxyfluores cein-5Ј-GACTTGCAGGCC-3Ј (positions 840 to 851). PCR amplifications were performed in 25-l reaction volumes including 1ϫ TaqMan Universal Master Mix (A...

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BackgroundOutcome of patients with streptococcal prosthetic joint infections (PJIs) is not well known.MethodsWe performed a retrospective multicenter cohort study that involved patients with total hip/knee prosthetic joint (THP/TKP) infections due to Streptococcus spp. from 2001 through 2009.ResultsNinety-five streptococcal PJI episodes (50 THP and 45 TKP) in 87 patients of mean age 69.1 ± 13.7 years met the inclusion criteria. In all, 55 out of 95 cases (57.9 %) were treated with debridement and retention of the infected implants with antibiotic therapy (DAIR). Rifampicin-combinations, including with levofloxacin, were used in 52 (54.7 %) and 28 (29.5 %) cases, respectively. After a mean follow-up period of 895 days (IQR: 395–1649), the remission rate was 70.5 % (67/95). Patients with PJIs due to S. agalactiae failed in the same proportion as in the other patients (10/37 (27.1 %) versus 19/58 (32.7 %); p = .55). In the univariate analysis, antibiotic monotherapy, DAIR, antibiotic treatments other than rifampicin-combinations, and TKP were all associated with a worse outcome. The only independent variable significantly associated with the patients’ outcomes was the location of the prosthesis (i.e., hip versus knee) (OR = 0.19; 95 % CI 0.04–0.93; p value 0.04).ConclusionsThe prognosis of streptococcal PJIs may not be as good as previously reported, especially for patients with an infected total knee arthroplasty. Rifampicin combinations, especially with levofloxacin, appear to be suitable antibiotic regimens for these patients.