Using PCR testing on BAL fluid, Denning et al (in Manchester UK) found Aspergillus DNA in 4 of 11 (36%) healthy volunteers; 21 of 22 patients with culture/microscopy-proven invasive aspergillosis; and 70-80% of patients with allergic bronchopulmonary aspergillosis or chronic pulmonary aspergillosis. Culture was positive in none of the ABPA patients, and only 17% of the CPA [... read more]
Last month we reported the success of the MTB/RIF test in identifying tuberculosis when smears are negative, which occurs ~40% of the time in TB-HIV coinfection. Shah et al publish their success with the sputum MODS assay in an all-HIV clinic in South Africa. The MODS is a rapid (~7-day) culture that also identifies multi-drug resistant TB. The test was 85% sensitive [... read more]
De Smet et al reheat the data from their 2009 NEJM study, in which they cluster-randomized and crossed-over 5,939 patients staying >48hrs in 13 Dutch ICUs to receive either 1) standard care; 2) selective oropharyngeal decontamination (topical amphotericin B, colistin, and tobramycin in the oropharynx), or 3) selective digestive tract decontamination (the same drugs in the mouth, stomach, [... read more]
Pseudomonas pneumonia part II, antibiotic therapy, resistance, pharmacodynamics, Sun H et al, CHEST 2011;139:1172-1185. Review.
Databases suggest that 60-70% of patients with severe respiratory failure due to H1N1 received steroids. Brun-Buisson et allooked back at a French registry including 208 patients with H1N1 and ARDS, 83 of whom received steroids. They found a hazard ratio of 2.4 for death associated with steroid administration, rising to 2.8 after applying their propensity scoring [... read more]
Four-drug therapy (RIPE) requires high patient commitment and imposes logistical demands on health systems in developing countries. Lienhardt et al report that a fixed-drug combination (FDC) of rifampin, isoniazid, pyrazinamide, and ethambutol was noninferior in producing negative cultures at 18 months compared to taking the drugs separately (both arms ~94% cure rate) in Africa, Asia and Latin [... read more]
Maki et al randomized 407 patients at 25 dialysis units to have their catheters “locked” for up to 6 months with either heparin, or “C-MB-P solution” (citric acid, methylene blue, and propylparaben). The patients getting the antimicrobial potion had a 0.29 relative risk for bloodstream infection (BSI) without loss of catheter patency. (n=407) Crit Care Med 2011;39:613-620.
A systematic review of 3 trials (n=337) by the Bed Head Elevation Study Group (not to be confused with the Bedhead photo group) found no good evidence that head-of-bed (HOB) elevation to 45′ helps or harms in any way (pneumonia, decubiti, mortality, VTE, or hemodynamic instability). Nevertheless, a consensus panel of 22 experts agrees with previous [... read more]
Interferon-gamma release assays in the diagnosis of latent tuberculosis infection: Herrera V, Clin Infect Dis 2011;52:1031-1037.
The MTB/RIF test is a rapid nucleic acid amplification test for TB. In a rollout in developing countries on 6,648 patients, the test was 90% sensitive for active TB, vs. 67% for smear microscopy (sputum culture was the gold standard). In smear-negative, culture-positive TB, the test was 77% sensitive and 99% specific. It also accurately detects rifampin [... read more]
After implementing an “MRSA bundle” in 2007 including nasal surveillance, contact precautions for positive patients, hand hygiene, and culture-indoctrination of employees, MRSA infections among all VA hospital ICUs fell from 1.64 to 0.62 per 1000 patient-days (a 62% reduction, p<0.001). MRSA infections on the wards fell from 0.47 to 0.26 per 1000 patient-days (45% reduction, [... read more]
Huskins et al cluster-randomized 18 ICUs to an intervention of surveillance cultures with contact precautions for positive patients, or a control of no cultures and universal precautions (gloves). The intervention ICUs used contact precautions more frequently (51% vs. 38%), but had the same MRSA/VRE colonization/infection rates, the primary endpoint (40 vs 35%, p=0.35). Clinician compliance [... read more]
Overt vancomycin resistance in MRSA is still unusual, but ID docs are worried about the bug’s rising minimum inhibitory concentrations in some regions, with MICs > 1 mcg/mL associated with worse outcomes. Kullar et al retrospectively looked at Detroit’s Henry Ford Hospital’s 5-year micro data in 320 patients with MRSA bacteremia, reporting a 52% rate [... read more]
Latent tuberculosis infection in the U.S.: Horsburgh CR, NEJM 2011;364:1441-1448
Death, long hospital stays, and treatment failures are more likely when vancomycin is used for MRSA bacteremia with minimum inhibitory concentrations (MIC) > 1 mcg/mL. Lubin et al propose a clinical prediction rule to predict relative vancomycin resistance, based on a retrospective analysis of 272 patients with MRSA bacteremia at Tufts. Oversimplifying slightly: Having less [... read more]
Molecular diagnosis of respiratory tract infection in COPD exacerbations: Sethi S, Clin Infect Dis 2011;52 (supplement 4):S290-294.
Patel et al ran 9,999 computer simulations using various vancomycin doses and MICs. When the MIC was 2.0 or greater, 2 g IV q12 hours failed to achieve target drug levels 57% of the time, with 35% predicted nephrotoxicity. But…it’s also true that multiple vancomycin models have been published, which are each internally valid using their own [... read more]
Mucormycosis: clinical presentations and management: Sun H, Lancet Infect Dis 2011;11:301-311.
Probiotics and lung diseases: Forsythe P, CHEST 2011;139:901-908.
Pseudomonas pneumonia: Epidemiology, clinical diagnosis, source (Part 1) Fujitani S et al, CHEST 2011;139:909-919.