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Pneumocystis jirovecii (carinii) pneumonia (PJP) is a major cause of disease in immunocompromised individuals. However, until recently no reliable and specific serological parameters for the diagnosis of PJP have been available. (1 → 3)-β-D-Glucan (BG) is a cell wall component of P. jirovecii and of various other fungi. Data from the past few years have pointed to serum measurement of BG as a promising new tool for the diagnosis of PJP. We therefore conducted a retrospective study on 50 patients with PJP and 50 immunocompromised control patients to evaluate the diagnostic performance of serum BG measurement. Our results show an excellent diagnostic performance with a sensitivity of 98.0% and a specificity of 94%. While the positive predictive value was only 64.7%, the negative predictive value was 99.8% and therefore a negative BG result almost rules out PJP. BG levels were already strongly elevated in an average of 5 days and up to 21 days before microbiological diagnosis demonstrating that the diagnosis could have been confirmed earlier. BG levels at diagnosis and maximum BG levels during follow-up did not correlate with the outcome of patients or with the P. jirovecii burden in the lung as detected by Real-Time PCR. Therefore, absolute BG levels seem to be of no prognostic value. Altogether, BG is a reliable parameter for the diagnosis of PJP and could be used as a preliminary test for patients at risk before a bronchoalveolar lavage is performed. [ABSTRACT FROM AUTHOR]

One hundred and three patients who had previously tested positive for community-acquired methicillin-resistant Staphylococcus aureus (cMRSA) were followed up for a mean time of 32.6 months. Eighty patients had a history of skin or soft tissue infection, and the remainder were mostly asymptomatic carriers. Of 103 patients, only two reported ongoing symptoms with abscess formation. Of 81 nasal swabs available, 30.9% were positive for S. aureus but only four yielded Panton-Valentine leukocidin-positive methicillin-resistant S. aureus. In summary, we were unable to find persistent health issues or nasal colonization with cMRSA in a cohort of previously cMRSA-infected/colonized patients. [ABSTRACT FROM AUTHOR]

Abstract: Background: HIV-1 viral load assays are critical tools to monitor antiretroviral therapy efficacy in HIV-infected patients. Two assays based on real-time PCR are available, the Abbott Real-Time HIV-1 assay (Abbott assay) and the new Roche COBAS® AmpliPrep/COBAS® TaqMan® HIV-1 test, v. 2.0 (TaqMan® test v2.0). Objectives: We have compared the performance of the two assays in 546 clinical plasma specimens of group M strains from Luxembourg and Rwanda. Study design: Our analyses focused on subtype inclusivity and platforms accuracy for 328 low level viremia samples. Results: Strong agreement and linear correlation were observed between the two assays (R 2 =0.95) over a wide dynamic range. Bland–Altman analysis showed a mean difference of 0.04log10 indicating minimal overall viral load quantification differences between both platforms. One subtype C was severely underquantified by TaqMan® test v2.0 for which sequence analysis revealed multiple mismatches between the viral sequence and the primer/probe regions. A non significant lower quantification of the Abbott assay was shown for subtype A1 with a mean log10 difference of 0.24. For specimens under 200cp/mL, the overall agreement was 90% at the cut-off of 50cp/mL and 67% at assay''s lower limit of detection of 20 and 40cp/mL. 309 samples were retested by the COBAS® AMPLICOR® HIV-1 MONITOR Test, v. 1.5 and a lack of agreement between the three assays around their lower limit of quantification was revealed. Conclusions: Both real-time tests were closely comparable in the quantification of viral load specimens of ten HIV-1 subtypes and recombinant forms. [Copyright &y& Elsevier]

Objectives Aim of this study was to detect microorganisms in fetal membranes and placental tissue in preterm chorioamnionitis by combining fluorescence in situ hybridization (FISH) with broad range PCR. The combination of the two molecular techniques enables identification and localization of the microorganisms within the tissue, confirming their clinical relevance. Methods In a prospective cohort study, we compared 31 women with preterm premature rupture of membranes or preterm labour and preterm delivery by caesarean section with a control group of 26 women undergoing elective caesarean section at term. Fetal membranes and placental tissue were analysed by FISH and broad range 16S rRNA-gene PCR and sequencing. Results For 20 women in the preterm group, caesarean section was performed because of a clinical diagnosis of chorioamnionitis. Microorganisms were detected in the tissues by both molecular techniques in 11 out of 20 women. Among those, Ureaplasma spp. was most abundant, with five cases that remained culture-negative and would have been missed by routine diagnostic procedures. Other infections were caused by Staphylococcus aureus , Streptococcus mitis or Escherichia coli . FISH and PCR were negative for all women without suspected chorioamnionitis and for the control group. Conclusions Combination of FISH with broad-range PCR and sequencing permitted unambiguous identification of the causative microorganisms in chorioamnionitis. The high prevalence of Ureaplasma spp. should lead to a re-evaluation of its clinical significance and possible therapeutic consequences. [ABSTRACT FROM AUTHOR]