Citations

Objectives To perform a systematic review and meta-analysis including all the current studies to assess the accuracy of pulmonary embolism rule-out criteria (PERC) in ruling out pulmonary embolism (PE). Methods We conducted a comprehensive search of the major databases (Ovid Medline In-Process & Other Non-Indexed Citations, Ovid MEDLINE, Ovid EMBASE, Ovid PsycInfo, Ovid Cochrane Central Register of Controlled Trials, Ovid Cochrane Database of Systematic Reviews and Scopus) and references of potentially eligible articles and conference proceedings of major emergency medicine organisations through May 2012. We included all original research studies conducted in emergency departments on diagnostic performance of PERC. Two reviewers independently identified the eligible studies and extracted data. Sensitivity, specificity and likelihood ratios were calculated using contingency tables. Results 12 studies including 13 cohorts (three retrospective, 10 prospective) were included, comprising of 14 844 patients from six countries. 12 cohorts were urban and one was rural. Pooled (95% CI) sensitivity, specificity, positive and negative likelihood ratio were 0.97 (0.96 to 0.98), 0.22 (0.22 to 0.23), 1.22 (1.16 to 1.29) and 0.17 (0.13 to 0.23), respectively. The pooled (95% CI) diagnostic OR was 7.4 (5.5–9.8). On meta-regression analysis, there was no significant difference between PE prevalence and PERC diagnostic performance (coefficient (SE) of −0.032 (0.022), p=0.173) or on relative diagnostic OR (0.97, 95% CI 0.92 to 1.02). Significant heterogeneity was observed in specificity (I2=97.4%) and positive likelihood ratio (I2=89.1%). Conclusions Because of the high sensitivity and low negative likelihood ratio, PERC rule can be used confidently in clinically low probability population settings.

Background: Chronic migraine (CM) is a debilitating neurological disorder with few treatment options. Peripheral nerve stimulation (PNS) of the occipital nerves is a potentially promising therapy for CM patients. Methods: In this randomized, controlled multicenter study, patients diagnosed with CM were implanted with a neurostimulation device near the occipital nerves and randomized 2:1 to active ( n = 105) or sham ( n = 52) stimulation. The primary endpoint was a difference in the percentage of responders (defined as patients that achieved a ≥50% reduction in mean daily visual analog scale scores) in each group at 12 weeks. Results: There was not a significant difference in the percentage of responders in the Active compared with the Control group (95% lower confidence bound (LCB) of −0.06; p = 0.55). However, there was a significant difference in the percentage of patients that achieved a 30% reduction ( p = 0.01). Importantly, compared with sham-treated patients, there were also significant differences in reduction of number of headache days (Active Group = 6.1, baseline = 22.4; Control Group = 3.0, baseline = 20.1; p = 0.008), migraine-related disability ( p = 0.001) and direct reports of pain relief ( p = 0.001). The most common adverse event was persistent implant site pain. Conclusion: Although this study failed to meet its primary endpoint, this is the first large-scale study of PNS of the occipital nerves in CM patients that showed significant reductions in pain, headache days, and migraine-related disability. Additional controlled studies using endpoints that have recently been identified and accepted as clinically meaningful are warranted in this highly disabled patient population with a large unmet medical need. Trial registration: Clinical trials.gov (NCT00615342).

AbstractHemodialysis (HD) exposes end‐stage renal disease patients to significantly higher risks for Hepatitis B Virus (HBV) infection, a major public health scourge. Therefore, current US CDC guidelines, last revised in 2001, call for monthly HbsAg tests. The charge to Medicare per HbsAg test is $100. In an economic analysis, we hypothesized that in the new environment of Medicare Fee Bundling, this is unwise and wasteful if de novo HBV infection rate among HD patients is <1%. We determined de novo HBV infection rate among a Mayo Clinic HD cohort, July 2000–July 2010. A retrospective analysis of all relevant medical records of the cohort was completed to identify de novo HBV infection. Nine hundred sixty‐five HD patients were analyzed. One case of de novo HBV infection was identified in a 54‐year old known IV drug user, a previous Hepatitis C carrier. This translates to a de novo HBV case incidence rate of 0.1%. De novo HBV infection among HD patients in the US, 2000–2010, is only 0.1%. In the early 1970s, rates were as high as 30%. We recommend 3‐monthly HbsAg testing, but to continue current monthly testing for IV drug users and other high‐risk groups. Huge cost savings would result, without any compromise of quality outcomes. With over 500,000 HD patients, this represents a mind‐boggling $40 billion savings in Medicare charges over 10 years. The US CDC should revise these outdated guidelines, last revised in 2001, to fall in line with current clinical realities on the ground.

In a mouse model of the human disease pulmonary lymphangioleiomyomatosis, treatment with rapamycin plus simvastatin prevented alveolar space enlargement and growth of TSC2-null lesions.