Diversity and clinical impact of Acinetobacter baumannii colonization and infection at a military medical center.

The epidemiology of Acinetobacter baumannii emerging in combat casualties is poorly understood. We analyzed 65 (54 nonreplicate) Acinetobacter isolates from 48 patients (46 hospitalized and 2 outpatient trainees entering the military) from October 2004 to October 2005 for genotypic similarities, time-space relatedness, and antibiotic susceptibility. Clinical and surveillance cultures were compared by amplified fragment length polymorphism (AFLP) genomic fingerprinting to each other and to strains of a reference database. Antibiotic susceptibility was determined, and multiplex PCR was performed for OXA-23-like, -24-like, -51-like, and -58-like carbapenemases. Records were reviewed for overlapping hospital stays of the most frequent genotypes, and risk ratios were calculated for any association of genotype with severity of Acute Physiology and Chronic Health Evaluation II (APACHE II) score or injury severity score (ISS) and previous antibiotic use. Nineteen genotypes were identified; two predominated, one consistent with an emerging novel international clone and the other unique to our database. Both predominant genotypes were carbapenem resistant, were present at another hospital before patients' admission to our facility, and were associated with higher APACHE II scores, higher ISSs, and previous carbapenem antibiotics in comparison with other genotypes. One predominated in wound and respiratory isolates, and the other predominated in wound and skin surveillance samples. Several other genotypes were identified as European clones I to III. Acinetobacter genotypes from recruits upon entry to the military, unlike those in hospitalized patients, did not include carbapenem-resistant genotypes. Acinetobacter species isolated from battlefield casualties are diverse, including genotypes belonging to European clones I to III. Two carbapenem-resistant genotypes were epidemic, one of which appeared to belong to a novel international clone.

Occupational transmission of Acinetobacter baumannii from a United States serviceman wounded in Iraq to a health care worker.

BACKGROUND: Acinetobacter baumannii is increasingly recognized as being a significant pathogen associated with nosocomial outbreaks in both civilian and military treatment facilities. Current analyses of these outbreaks frequently describe patient-to-patient transmission. To date, occupational transmission of A. baumannii from a patient to a health care worker (HCW) has not been reported. We initiated an investigation of an HCW with a complicated case of A. baumannii pneumonia to determine whether a link existed between her illness and A. baumannii-infected patients in a military treatment facility who had been entrusted to her care. METHODS: Pulsed-field gel electrophoresis and polymerase chain reaction/electrospray ionization mass spectrometry, a form of multilocus sequencing typing, were done to determine clonality. To further characterize the isolates, we performed a genetic analysis of resistance determinants. RESULTS AND CONCLUSIONS: A "look-back" analysis revealed that the multidrug resistant A. baumannii recovered from the HCW and from a patient in her care were indistinguishable by pulsed-field gel electrophoresis. In addition, polymerase chain reaction/electrospray ionization mass spectrometry indicated that the isolates were similar to strains of A. baumannii derived from European clone type II (Walter Reed Army Medical Center strain type 11). The exposure of the HCW to the index patient lasted for only 30 min and involved endotracheal suctioning without use of an HCW mask. An examination of 90 A. baumannii isolates collected during this investigation showed that 2 major and multiple minor clone types were present and that the isolates from the HCW and from the index patient were the most prevalent clone type. Occupational transmission likely occurred in the hospital; HCWs caring for patients infected with A. baumannii should be aware of this potential mode of infection spread.

In vitro antifungal efficacy of four irrigants as a final rinse.

The purpose of this study was to compare the antifungal efficacy of 6% sodium hypochlorite (NaOCl), 2% chlorhexidine gluconate (CHX), 17% ethylene-diaminetetraacetic acid (EDTA), and BioPure MTAD as a final rinse on Candida albicans in vitro. Forty-eight, single rooted teeth were randomly divided into four groups each with a positive and a negative control. After root canal preparation, experimental teeth were inoculated with Candida albicans (ATCC 60193) and incubated for 72 hours. The groups were rinsed as follows: 1 ml of 6% NaOCl, 0.2 ml of 2% CHX, 1 ml of 17% EDTA, and 5 ml of BioPure MTAD. Aliquots from the experimental teeth were plated on Sabouraud 4% dextrose agar plates and colony-forming units were counted as a measure of antifungal activity. The results showed that 6% NaOCl and 2% CHX were equally effective and statistically significantly superior to BioPure MTAD and 17% EDTA (p < 0.05) in antifungal activity.

Pseudomonas putida war wound infection in a US Marine: a case report and review of the literature.

US service members are returning from the war in Iraq and Afghanistan with wound infections due to uncommon bacteria. Pseudomonas putida, a member of the fluorescent group of pseudomonads, primarily causes infection in immunosuppressed hosts and patients with invasive medical devices. P. putida has been implicated in outbreaks often traced to a contaminated fluid and is a rare cause of clinical infection. However, it should be considered a pathogen when isolated from pure culture. The objective of this article is to present a case report of a P. putida war wound infection, review previous P. putida infections, and provide a concise review of the epidemiology, risk factors, and management of infections due to this organism.