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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]

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]