Comparison of rapid immunochromatographic assays using sputum and urine for Streptococcus pneumoniae detection in adult patients with respiratory tract infection

Aim: Streptococcus pneumoniae is the most frequently detected bacterium in pneumonia. RAPIRUN Streptococcus pneumoniae (RAPIRUN) using sputum and BinaxNow Streptococcus pneumoniae (BinaxNow) using urine have been used as rapid diagnostic methods for S. pneumoniae detection in Japan; however, their correlation with quantitative culture tests has not been well evaluated.Methods: A prospective study was conducted on adult patients with respiratory tract infections whose sputum and urine samples were available in six hospitals. Sputum and urine samples were tested at each site, and quantitative sputum cultures were performed. The performance of RAPIRUN and BinaxNow was compared in cases in which quantitative culture showed S. pneumoniae.Results: A total of 192 patients were analyzed. Of these, 167 were diagnosed with pneumonia (87.0%) including 161 of community-acquired pneumonia. Of the 192 cases, 86 (44.8%) were culture-proven for S. pneumoniae. There were 83 and 57 RAPIRUN- and BinaxNow-positive cases, respectively. The sensitivity and specificity of RAPIRUN were 84.9% and 90.6%, respectively, and those of BinaxNOW were 55.8% and 91.5%, respectively, indicating that RAPIRUN was significantly superior in sensitivity (p < 0.0001) with almost equal specificity (p = 0.317). Positive and negative percent agreements of both tests were 59.3% (κ, 0.114 [95% CI, 0.053–0.281]) and 99.1% (κ, 0.942 [95% CI, 0.830–1]), respectively, indicating they were well matched in specificity but not in sensitivity. The positivity rate of RAPIRUN increased with an increase in the number of bacteria (p< 0.0001) but not BinaxNow (p = 0.275).Conclusion: In adult patients with respiratory tract infections in whom sputum collection is feasible, RAPIRUN will increase the diagnostic efficacy of S. pneumoniae infection

A high α1-antitrypsin/interleukin-10 ratio predicts bacterial pneumonia in adults with community-acquired pneumonia: a prospective cohort study

Abstract Background Current microbiological tests fail to identify the causative microorganism in more than half of all pneumonia cases. We explored biomarkers that could be used for differentiating between bacterial and viral pneumonia in patients with community-acquired pneumonia (CAP). Methods In this prospective cohort study conducted in Japan, data obtained from adult patients with bacterial pneumonia, including bacterial and viral coinfections (bacterial pneumonia [BP] group), and purely viral pneumonia (VP group) at diagnosis were analyzed using multivariate logistic regression analysis to identify predictors of bacterial pneumonia. Furthermore, a decision tree was developed using the predictors. Results A total of 210 patients were analyzed. The BP and VP groups comprised 108 and 18 patients, respectively. The other 84 patients had no identified causative microorganism. The two groups shared similar characteristics, including disease severity; however, a significant difference (p < 0.05) was observed between the two groups regarding sputum type; sputum volume score; neutrophil counts; and serum levels of interleukin (IL)-8, IL-10, and α1-antitrypsin (AAT). Sputum volume score (p < 0.001), IL-10 (p < 0.001), and AAT (p = 0.008) were ultimately identified as predictors of BP. The area under the curve for these three variables on the receiver operating characteristic (ROC) curve was 0.927 (95% confidence interval [CI]: 0.881–0.974). The ROC curve for sputum volume score and an AAT/IL-10 ratio showed a diagnostic cutoff of 1 + and 65, respectively. Logistic regression analysis using dichotomized variables at the cutoff values showed that the odds ratios for the diagnosis of BP were 10.4 (95% CI: 2.2–50.2) for sputum volume score (absence vs. presence) and 19.8 (95% CI: 4.7–83.2) for AAT/IL-10 ratio (< 65 vs. ≥ 65). Conclusions Considering that obtaining a definitive etiologic diagnosis with the current testing methods is difficult and time consuming, a decision tree with two predictors, namely sputum volume and the AAT/IL-10 ratio, can be useful in predicting BP among patients diagnosed with CAP and facilitating the appropriate use of antibiotics. Trial registration UMIN000034673 registered on November 29, 2018

Genomewide High-Density SNP Linkage Analysis of 236 Japanese Families Supports the Existence of Schizophrenia Susceptibility Loci on Chromosomes 1p, 14q, and 20p

The Japanese Schizophrenia Sib-Pair Linkage Group (JSSLG) is a multisite collaborative study group that was organized to create a national resource for affected sib pair (ASP) studies of schizophrenia in Japan. We used a high-density single-nucleotide–polymorphism (SNP) genotyping assay, the Illumina BeadArray linkage mapping panel (version 4) comprising 5,861 SNPs, to perform a genomewide linkage analysis of JSSLG samples comprising 236 Japanese families with 268 nonindependent ASPs with schizophrenia. All subjects were Japanese. Among these families, 122 families comprised the same subjects analyzed with short tandem repeat markers. All the probands and their siblings, with the exception of seven siblings with schizoaffective disorder, had schizophrenia. After excluding SNPs with high linkage disequilibrium, we found significant evidence of linkage of schizophrenia to chromosome 1p21.2-1p13.2 (LOD=3.39) and suggestive evidence of linkage to 14q11.2 (LOD=2.87), 14q11.2-q13.2 (LOD=2.33), and 20p12.1-p11.2 (LOD=2.33). Although linkage to these regions has received little attention, these regions are included in or partially overlap the 10 regions reported by Lewis et al. that passed the two aggregate criteria of a meta-analysis. Results of the present study—which, to our knowledge, is the first genomewide analysis of schizophrenia in ASPs of a single Asian ethnicity that is comparable to the analyses done of ASPs of European descent—indicate the existence of schizophrenia susceptibility loci that are common to different ethnic groups but that likely have different ethnicity-specific effects