Faculty Bibliography

Clinical guidelines play a central role in day-to-day practice. We assessed the degree of incorporation of cost analyses to guidelines and identified modifiable characteristics that could affect the level of incorporation.We selected the 100 most cited guidelines listed on the National Guideline Clearinghouse (http://www.guideline.gov) and determined the number of guidelines that used cost analyses in their reasoning and the overall percentage of incorporation of relevant cost analyses available in PubMed. Differences between medical specialties were also studied. Then, we performed a case-control study using incorporated and not incorporated cost analyses after 1:1 matching by study subject and compared them by the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) statement requirements and other criteria.We found that 57% of guidelines do not use any cost justification. Guidelines incorporate a weighted average of 6.0% (95% confidence interval [CI] 4.3-7.9) among 3396 available cost analyses, with cardiology and infectious diseases guidelines incorporating 10.8% (95% CI 5.3-18.1) and 9.9% (95% CI 3.9- 18.2), respectively, and hematology/oncology and urology guidelines incorporating 4.5% (95% CI 1.6-8.6) and 1.6% (95% CI 0.4-3.5), respectively. Based on the CHEERS requirements, the mean number of items reported by the 148 incorporated cost analyses was 18.6 (SD = 3.7), a small but significant difference over controls (17.8 items; P = 0.02). Included analyses were also more likely to directly relate cost reductions to healthcare outcomes (92.6% vs 81.1%, P = 0.004) and declare the funding source (72.3% vs 53.4%, P < 0.001), while similar number of cases and controls reported a noncommercial funding source (71% vs 72.7%; P = 0.8).Guidelines remain an underused mechanism for the cost-effective allocation of available resources and a minority of practice guidelines incorporates cost analyses utilizing only 6% of the available cost analyses. Fulfilling the CHEERS requirements, directly relating costs with healthcare outcomes and transparently declaring the funding source seem to be valued by guideline-writing committees.

BACKGROUND:Graft-versus-host Disease (GvHD) prophylaxis after allogeneic hematopoietic stem-cell transplantation (HSCT) is an ongoing effort but relative effects of different policies are not systematically explored. METHODS:We systematically reviewed 30-year evidence on GvHD prophylaxis and quantified the relative effect of different policies using a network meta-analysis. We searched PubMed and the Cochrane Library for randomized studies on the topic. The primary outcome of interest was grade II-IV acute GvHD over 0 or I (with odds ratio OR <1 denoting benefit). FINDINGS/RESULTS:Thirty-three eligible studies that enrolled 3,440 patients (published up to June 2014), provided data on seven immunosuppressive drugs namely cyclosporin A (CsA), methotrexate (MTX), anti-thymocyte globulin (ATG), mycophenolate mofetil (MMF), tacrolimus, sirolimus or corticosteroids and their combinations to calculate 14 direct and 21 indirect effects. The majority of trials (32/33) referred to myeloablative conditioning and sibling transplants (25/33). Tacrolimus/MTX (OR 0.44; 95% 0.27-0.70, number needed to treat to benefit, i.e. to avert a case of II-IV GvHD, NNTB = 5) and ATG/CsA/MTX (OR 0.45; 95%CI 0.26-0.78; NNTB = 5) were superior over CsA/MTX. ATG/CsA/MTX did not differ from tacrolimus/MTX (indirect evidence). Sirolimus-based prophylaxis outperformed CsA/MTX (OR 0.10; 95%CI 0.02-0.49, NNTB = 4) and marginally outperformed tacrolimus/MTX (OR 0.22; 95%CI 0.05-1.11). Add-on corticosteroids had no benefit over CsA/MTX. CONCLUSIONS:Tacrolimus/MTX and ATG/CsA/MTX were the outperformers over CsA/MTX, but sirolimus-based regimens showed also potential. More randomized data are needed for reduced-intensity conditioning, as well as for MMF and sirolimus-containing regimens.

BACKGROUND:Antimicrobial lock solutions may be an effective strategy to prevent catheter-associated infections. However, there remains concern about their efficacy and safety. METHODS:To investigate the efficacy of antimicrobial lock therapy to prevent central line-associated bloodstream infections (CLABSIs), we performed a systematic search of PubMed, Embase, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov, from the earliest date up to 31 December 2013. Studies were eligible if they were randomized controlled trials comparing antimicrobial lock solutions to heparin and if they provided an appropriate definition of infection. RESULTS:The 23 included studies reported data on 2896 patients, who were predominantly adult patients undergoing hemodialysis (16/23 studies), but also adult and pediatric oncology patients, critically ill neonates, and patients receiving total parenteral nutrition. The use of antimicrobial lock solutions led to a 69% reduction in CLABSI rate (relative risk [RR], 0.31; 95% confidence interval [CI], .24-.40) and a 32% reduction in the rate of exit site infections (RR, 0.68; 95% CI, .49-.95) compared with heparin, without significantly affecting catheter failure due to noninfectious complications (RR, 0.83; 95% CI, .65-1.06). All-cause mortality was not different between the groups (RR, 0.84; 95% CI .64-1.12). Neither the type of antimicrobial solution nor the population studied, affected the relative reduction in CLABSIs, which also remained significant among studies reporting baseline infection rates of <1.15 per 1000 catheter-days, and studies providing data for catheter-related bloodstream infections. Publication and selective reporting bias are a concern in our study and should be acknowledged. CONCLUSIONS:Antimicrobial lock solutions are effective in reducing risk of CLABSI, and this effect appears to be additive to traditional prevention measures.

Invasive aspergillosis is a difficult-to-diagnose infection with a high mortality rate that affects high-risk groups such as patients with neutropenia and hematologic malignancies. We performed a bivariate meta-analysis of diagnostic data for an Aspergillus sp. PCR assay with blood specimens from high-risk hematology patients. We included all studies involving human subjects that assessed the performance of any PCR assay for invasive aspergillosis in whole blood or serum and that used the European Organization for the treatment of Cancer/Mycoses Study Group criteria as a reference standard. Three investigators independently searched the literature for eligible studies and extracted the data. Out of a total of 37 studies, 25 met strict quality criteria and were included in our evidence synthesis. Twenty-five studies with 2,595 patients were analyzed. The pooled diagnostic performance of whole-blood and serum PCR assays was moderate, with a sensitivity and specificity of 84% (95% confidence interval [CI], 75 to 91%) and 76% (95% CI, 65 to 84%), respectively, suggesting that a positive or negative result is unable, on its own, to confirm or exclude a suspected infection. The performance of a PCR assay of serum was not significantly different from that of whole blood. Notably, at least two positive PCR test results were found to have a specificity of 95% and a sensitivity of 64% for invasive infection, achieving a high positive likelihood ratio of 12.8. Importantly, the European Aspergillus PCR Initiative (EAPCRI) recommendations improved the performance of the PCR even further when at least two positive specimens were used to define PCR positivity. In conclusion, two positive PCR results should be considered highly indicative of an active Aspergillus sp. infection. Use of the EAPCRI recommendations by clinical laboratories can further enhance PCR performance.

BACKGROUND:Human immunodeficiency virus (HIV)-infected individuals who are colonized with methicillin-resistant Staphylococcus aureus (MRSA) have increased risk for MRSA infection. We conducted a meta-analysis of published studies to estimate the prevalence of MRSA colonization in this population. METHODS:We performed a systematic literature review and meta-analysis. The PubMed and Embase databases were searched and studies reporting prevalence of MRSA colonization among HIV-infected individuals were included. RESULTS:Among 7940 citations, 32 studies reporting data on 6558 HIV-infected individuals were considered eligible for our meta-analysis. We found that 6.9% (95% confidence interval [CI], 4.8-9.3) of individuals with HIV infection are MRSA carriers, with the corresponding figure across North American studies being 8.8% (95% CI, 6.0-12.2). History of hospitalization during the previous 12 months was associated with a 3.1 times higher risk of MRSA colonization (risk ratio [RR], 3.11 [95% CI, 1.62-5.98]). Previous or current incarceration was also associated with a higher risk for carriage (RR, 1.77 [95% CI, 1.26-2.48]). Current antiretroviral therapy or use of trimethoprim-sulfamethoxazole did not impact the risk of MRSA carriage (RR, 1.02 [95% CI, .64-1.63] and 1.45 [95% CI, .69-3.03], respectively). Extranasal screening increased the detection of MRSA colonization by at least 31.6% (95% CI, 15.8-50.0). The added yield from groin screening was 19.3% (95% CI, 11.5-28.5), from perirectal screening 18.5% (95% CI, 7.4-33.2), and from throat cultures 17.5% (95% CI, 12.0-24). CONCLUSIONS:Individuals with HIV infection constitute a highly vulnerable population for MRSA colonization, and prior exposure to hospital or incarceration are significant factors. Nasal screening alone will underestimate the rate of colonization by at least one-third.

Hematopoietic stem cell transplant (HSCT) recipients are at high risk of contracting Clostridium difficile infection (CDI). We systematically searched the PubMed and EMBASE databases through March 2014 and performed a random-effects meta-analysis to estimate the prevalence and trends of CDI over time. Among 48 eligible articles that included 12,025 patients at risk, we estimated that 7.9% (95% confidence interval [CI], 6.5% to 9.5%) of HSCT patients are diagnosed with CDI during the peri-transplantation and late post-transplantation periods, an estimation that is relatively consistent across studies (τ(2) = .032). Prevalence of CDI is significantly higher among the 5120 allogeneic patients (9.3% [95% CI, 7.0% to 11.9%]), compared with the 4665 autologous patients (5.2% [95% CI, 3.8% to 6.9%]) (P = .02), and as many as 1 of 10 allogeneic transplant recipients are expected to be diagnosed with CDI compared with 1 of 20 autologous transplantation patients. However, this difference did not reach statistical significance when stratified data from the same centers were examined (P = .11). Importantly, we found an increasing trend of CDI diagnosis both worldwide (P = .02) and across studies conducted in North America (P = .03) over the last 34 years. Notably, studies with a follow-up period that extended through the late post-transplantation period (after day +100) had a similar prevalence of CDI as those that followed patients only during the peri-transplantation period (up to day +100) (P = .94). In summary, CDI is common in the hematopoietic transplantation setting and the majority of infections occur in the peri-transplantation period. The prevalence is almost 9-times higher than that reported among all hospital stays, with an increasing trend over time.

Patients undergoing dialysis are particularly vulnerable to methicillin-resistant Staphylococcus aureus (MRSA) infections. We performed a meta-analysis of published studies to estimate the prevalence of MRSA colonization in dialysis patients, time trends, and long-term risk of subsequent MRSA infections. Our search of the PubMed and Embase databases returned 5743 nonduplicate citations, from which we identified 38 relevant studies that included data on 5596 dialysis patients. The estimated prevalence of MRSA colonization was 6.2% (95% confidence interval [95% CI], 4.2% to 8.5%). The prevalence increased over time but remained stable after 2000. Stratification of patients according to dialysis modality and setting revealed that 7.2% (95% CI, 4.9% to 9.9%) of patients on hemodialysis were colonized with MRSA compared with 1.3% (95% CI, 0.5% to 2.4%) of patients on peritoneal dialysis (P=0.01), and that a statistically significant difference existed in the percentage of colonized inpatients and outpatients (14.2% [95% CI, 8.0% to 21.8%] versus 5.4% [95% CI, 3.5% to 7.7%], respectively; P=0.04). Notably, the risk of developing MRSA infections increased among colonized hemodialysis patients compared with noncolonized patients (relative risk, 11.5 [95% CI, 4.7 to 28.0]). The long-term (6-20 months) probability of developing a MRSA infection was 19% among colonized hemodialysis patients compared with only 2% among noncolonized patients. In summary, 6.2% of dialysis patients are MRSA colonized, and the average prevalence of colonization has remained stable since 2000. Colonization in hemodialysis patients is associated with increased risk of MRSA infection.