Is the gram stain useful in the microbiologic diagnosis of VAP? A meta-analysis

In a meta-analysis examining respiratory specimen Gram stain for diagnosis of ventilator-associated pneumonia, absence of bacteria on Gram stain had a high negative predictive value, but a positive Gram stain correlated poorly with organisms recovered in culture. Rapid and accurate diagnosis of ventilator-associated pneumonia (VAP) is a major challenge and no generally accepted gold standard exists for VAP diagnosis. We conducted a meta-analysis to examine the role of respiratory specimen Gram stain to diagnose VAP, and the correlation with final culture results. In 21 studies, pooled sensitivity of Gram stain for VAP was 0.79 (95% confidence interval [CI], .77-0.81; P < .0001) and specificity was 0.75 (95% CI, .73-.78; P < .0001). Negative predictive value of Gram stain for a VAP prevalence of 20%-30% was 91%, suggesting that VAP is unlikely with a negative Gram stain but the positive predictive value of Gram stain was only 40%. Pooled kappa was 0.42 for gram-positive organisms and 0.34 for gram-negative organisms, suggesting fair concordance between organisms on Gram stain and recovery by culture. Therefore, a positive Gram stain should not be used to narrow anti-infective therapy until culture results become available.     

Lessons from the infuse trials: do we need a classification of bias in scientific publications and editorials?

The original 13 Food and Drug Administration industry-sponsored recombinant human bone morphogenetic protein-2 (rhBMP-2) trials investigating its use in spinal fusion all reported no associated adverse events. However, subsequent series of studies began reporting complication rates that were much higher than those that were initially published. Critical analysis of the original rhBMP-2 industry-associated data found systematic alignment favoring positive outcomes with no proven clinical advantage over bone graft. The sources of potential bias leading to inaccurate reporting of original rhBMP-2 efficacy and safety profile include flawed study design, methodological technique, data reporting and analysis, and significant financial conflict of interest. As such, to ensure the integrity of the scientific literature, further measures should be taken by researchers, surgeons, authors, journal editors and reviewers to assess for potential sources of bias.     

Evaluation of therapeutic potential of ivermectin against complete Freund's adjuvant-induced arthritis in rats: Involvement of inflammatory mediators

Rheumatoid arthritis is a chronic systemic inflammatory disease with genetic manifestations. According to recently published case reports, patients taking corticosteroid medication for the management of rheumatoid arthritis develop strongloidiasis and are at high risk of developing associated infections. This study explored the antiarthritic role of ivermectin, a drug used in the treatment of strongyloides and to compare its results with dexamethasone. Thirty-two male Wistar rats were randomly divided into four groups: control, diseased, dexamethasone, and ivermectin groups. Rheumatoid arthritis in all rats except the control group was induced by using complete Freund's adjuvant. After 7 days of rheumatoid arthritis induction, animals were treated with dexamethasone 5 mg/kg and ivermectin 6 mg/kg. Body weight, visual arthritic score, total leukocyte count, differential leukocyte count, proinflammatory genes, and histopathological findings were used to assess the effects of ivermectin on rheumatoid arthritis. Treatment with ivermectin showed a significant reduction in inflammatory cells levels, body weight, and visual arthritic score, indicating an improvement in the degree of inflammation as compared with the diseased group. Treatment with ivermectin and dexamethasone significantly reduced the augmentation in the mRNA expression levels of IL-17, TLR-2, TNF, and NF-κB as a result of arthritic development. Ivermectin treatment also showed a significant reduction in the severity of inflammation and destruction of joints and showed comparable effects to dexamethasone, a corticosteroid used for the treatment of rheumatoid arthritis. Ivermectin has significant antiarthritic properties and can be a novel treatment agent for the management of rheumatoid arthritis patients suffering from strongyloidiasis.     

Analysis of a non-lethal biallelic frameshift mutation in ZMPSTE24 reveals utilization of alternative translation initiation codons

Restrictive dermopathy (RD) is a lethal condition caused by biallelic loss-of-function mutations in ZMPSTE24, whereas mutations preserving residual enzymatic activity of the ZMPSTE24 protein lead to the milder mandibuloacral dysplasia with type B lipodystrophy (MADB) phenotype. Remarkably, we identified a homozygous, presumably loss-of-function mutation in ZMPSTE24 [c.28_29insA, p.(Leu10Tyrfs*37)] in two consanguineous Pakistani families segregating MADB. To clarify how lethal consequences are prevented in affected individuals, functional analysis was performed. Expression experiments supported utilization of two alternative translation initiation sites, preventing complete loss of protein function consistent with the relatively mild phenotypic outcome in affected patients. One of these alternative start codons is newly formed at the insertion site. Our findings indicate that the creation of new potential start codons through N-terminal mutations in other disease-associated genes should generally be taken into consideration in the variant interpretation process.