Kyle Petersen

An Outbreak of Multidrug-Resistant Acinetobacter baumannii-calcoaceticus Complex Infection in the US Military Health Care System Associated with Military Operations in Iraq

BACKGROUND We investigated an outbreak of multidrug-resistant Acinetobacter baumannii-calcoaceticus complex infection among US service members injured in Iraq. METHODS The investigation was conducted in Iraq and Kuwait, in the 2 military hospitals where the majority of injured service members were initially treated. After initially characterizing the outbreak, we evaluated 3 potential sources of infection for the period March 2003 to December 2004. The evaluation included screening samples that were obtained from the skin of patients for the presence of colonization and assessing the soil and health care environments for the presence of A. baumanii-calcoaceticus complex organisms. Isolates obtained from samples from patients in US Military treatment facilities, as well as environmental isolates, were genotypically characterized and compared using pulsed-field gel electrophoresis. RESULTS A. baumanii-calcoaceticus complex organisms were present on the skin in only 1 (0.6%) of 160 patients who were screened and in 1 (2%) of 49 soil samples. A. baumanii-calcoaceticus complex isolates were recovered from treatment areas in 7 of the 7 field hospitals sampled. Using pulsed-field gel electrophoresis, we identified 5 cluster groups in which isolates from patients were related to environmental isolates. One cluster included hospitalized patients who had not been deployed to Iraq. Among the clinical isolates, only imipenem, polymyxin B, and colistin demonstrated reliable in vitro antimicrobial activity. Generally, the environmental isolates were more drug susceptible than were the clinical isolates. CONCLUSIONS Our findings suggest that environmental contamination of field hospitals and infection transmission within health care facilities played a major role in this outbreak. On the basis of these findings, maintaining infection control throughout the military health care system is essential. Novel strategies may be required to prevent the transmission of pathogens in combat field hospitals.

Trauma-related Infections in Battlefield Casualties From Iraq

Objective:To describe risks for, and microbiology and antimicrobial resistance patterns of, war trauma associated infections from Operation Iraqi Freedom. Background:The invasion of Iraq resulted in casualties from high-velocity gunshot, shrapnel, and blunt trauma injuries as well as burns. Infectious complications of these unique war trauma injuries have not been described since the 1970s. Methods:Retrospective record review of all trauma casualties 5 to 65 years of age evacuated from the Iraqi theatre to U.S. Navy hospital ship, USNS Comfort March to May 2003.War trauma-associated infection was defined by positive culture from a wound or sterile body fluid (ie, blood, cerebrospinal fluid) and at least two of the following infection-associated signs/symptoms: fever, dehiscence, foul smell, peri-wound erythema, hypotension, and leukocytosis. A comparison of mechanisms of injury, demographics, and clinical variables was done using multivariate analysis. Results:Of 211 patients, 56 met criteria for infection. Infections were more common in blast injuries, soft tissue injuries, >3 wound sites, loss of limb, abdominal trauma, and higher Injury Severity Score (ISS). Wound infections accounted for 84% of cases, followed by bloodstream infections (38%). Infected were more likely to have had fever prior to arrival, and had higher probability of ICU admission and more surgical procedures. Acinetobacter species (36%) were the predominant organisms followed by Escherichia coli and Pseudomonas species (14% each). Conclusions:Similar to the Vietnam War experience, gram-negative rods, particularly Acinetobacter species, accounted for the majority of wound infections cared for on USNS Comfort during Operation Iraqi Freedom. Multidrug resistance was common, with the exception of the carbapenem class, limiting antibiotic therapy options.

Prevention of infections associated with combat-related extremity injuries

During combat operations, extremities continue to be the most common sites of injury with associated high rates of infectious complications. Overall, ∼ 15% of patients with extremity injuries develop osteomyelitis, and ∼ 17% of those infections relapse or recur. The bacteria infecting these wounds have included multidrug-resistant bacteria such as Acinetobacter baumannii, Pseudomonas aeruginosa, extended-spectrum β-lactamase-producing Klebsiella species and Escherichia coli, and methicillin-resistant Staphylococcus aureus. The goals of extremity injury care are to prevent infection, promote fracture healing, and restore function. In this review, we use a systematic assessment of military and civilian extremity trauma data to provide evidence-based recommendations for the varying management strategies to care for combat-related extremity injuries to decrease infection rates. We emphasize postinjury antimicrobial therapy, debridement and irrigation, and surgical wound management including addressing ongoing areas of controversy and needed research. In addition, we address adjuvants that are increasingly being examined, including local antimicrobial therapy, flap closure, oxygen therapy, negative pressure wound therapy, and wound effluent characterization. This evidence-based medicine review was produced to support the Guidelines for the Prevention of Infections Associated With Combat-Related Injuries: 2011 Update contained in this supplement of Journal of Trauma.

Guidelines for the prevention of infections associated with combat-related injuries: 2011 update endorsed by the infectious diseases society of America and the surgical infection society

Despite advances in resuscitation and surgical management of combat wounds, infection remains a concerning and potentially preventable complication of combat-related injuries. Interventions currently used to prevent these infections have not been either clearly defined or subjected to rigorous clinical trials. Current infection prevention measures and wound management practices are derived from retrospective review of wartime experiences, from civilian trauma data, and from in vitro and animal data. This update to the guidelines published in 2008 incorporates evidence that has become available since 2007. These guidelines focus on care provided within hours to days of injury, chiefly within the combat zone, to those combat-injured patients with open wounds or burns. New in this update are a consolidation of antimicrobial agent recommendations to a backbone of high-dose cefazolin with or without metronidazole for most postinjury indications, and recommendations for redosing of antimicrobial agents, for use of negative pressure wound therapy, and for oxygen supplementation in flight.

Guidelines for the prevention of infection after combat-related injuries.

Management of combat-related trauma is derived from skills and data collected in past conflicts and civilian trauma, and from information and experience obtained during ongoing conflicts. The best methods to prevent infections associated with injuries observed in military combat are not fully established. Current methods to prevent infections in these types of injuries are derived primarily from controlled trials of elective surgery and civilian trauma as well as retrospective studies of civilian and military trauma interventions. The following guidelines integrate available evidence and expert opinion, from within and outside of the US military medical community, to provide guidance to US military health care providers (deployed and in permanent medical treatment facilities) in the diagnosis, treatment, and prevention of infections in those individuals wounded in combat. These guidelines may be applicable to noncombat traumatic injuries under certain circumstances. Early wound cleansing and surgical debridement, antibiotics, bony stabilization, and maintenance of infection control measures are the essential components to diminish or prevent these infections. Future research should be directed at ideal treatment strategies for prevention of combat-related injury infections, including investigation of unique infection control techniques, more rapid diagnostic strategies for infection, and better defining the role of antimicrobial agents, including the appropriate spectrum of activity and duration.

The majority of US combat casualty soft-tissue wounds are not infected or colonized upon arrival or during treatment at a continental US military medical facility.

BACKGROUND The microbiology of war wounds has changed as medicine and warfare have evolved. This study was designed to determine the microbial flora and bacterial quantification of present-day war wounds in US troops from Iraq and Afghanistan upon arrival at the National Naval Medical Center (NNMC). METHODS Patients with extremity combat wounds treated with a vacuum-assisted wound closure device were enrolled in study. Wounds were biopsied every 48 to 72 hours with quantitative microbiology performed on all biopsies. RESULTS Two hundred forty-two wound biopsies from 34 patients; 167 (69%) showed no growth, and 75 (31%) showed positive growth. The incidence of any bacterial isolation from biopsies weekly from the time of injury was 28% (first), 31% (second), and 37% (≥third). Acinetobacter baumannii was the most prevalent isolate. CONCLUSIONS Most soft-tissue wounds from Iraq and Afghanistan do not have significant bacterial burden upon arrival to and during initial treatment at NNMC. Improved evaluation of combat wound microbiology at all levels of care is warranted to determine shifts in microbiology and to impact care practices.

Prevention and management of infections associated with combat-related head and neck injuries.

Maxillofacial injuries constitute 16% of all war-related injuries. This review focuses on data available from military and civilian studies to provide evidence-based recommendations for the modification of infections associated with combat-related injuries to the head and neck. The major emphasis of this review is on the study of subsequent infection, perioperative antimicrobial prophylaxis, debridement of devitalized tissue, optimal time to wound closure to achieve a water tight seal, wound irrigation with removal of debris and gross contaminants, fracture fixation, and removal of ocular foreign bodies with intravitreal antibiotics. Further studies are needed in combat-related injuries to the head and neck in military personnel to provide the highest evidence-based medicine recommendations.

Infection prevention and control in deployed military medical treatment facilities.

Infections have complicated the care of combat casualties throughout history and were at one time considered part of the natural history of combat trauma. Personnel who survived to reach medical care were expected to develop and possibly succumb to infections during their care in military hospitals. Initial care of war wounds continues to focus on rapid surgical care with debridement and irrigation, aimed at preventing local infection and sepsis with bacteria from the environment (e.g., clostridial gangrene) or the casualtys own flora. Over the past 150 years, with the revelation that pathogens can be spread from patient to patient and from healthcare providers to patients (including via unwashed hands of healthcare workers, the hospital environment and fomites), a focus on infection prevention and control aimed at decreasing transmission of pathogens and prevention of these infections has developed. Infections associated with combat-related injuries in the recent operations in Iraq and Afghanistan have predominantly been secondary to multidrug-resistant pathogens, likely acquired within the military healthcare system. These healthcare-associated infections seem to originate throughout the system, from deployed medical treatment facilities through the chain of care outside of the combat zone. Emphasis on infection prevention and control, including hand hygiene, isolation, cohorting, and antibiotic control measures, in deployed medical treatment facilities is essential to reducing these healthcare-associated infections. This review was produced to support the Guidelines for the Prevention of Infections Associated With Combat-Related Injuries: 2011 Update contained in this supplement of Journal of Trauma.

Prevention of Infections Associated with Combat-Related Burn Injuries

Burns are a very real component of combat-related injuries, and infections are the leading cause of mortality in burn casualties. The prevention of infection in the burn casualty transitioning from the battlefield to definitive care provided at the burn center is critical in reducing overall morbidity and mortality. This review highlights evidence-based medicine recommendations using military and civilian data to provide the most comprehensive, up-to-date management strategies for initial care of burned combat casualties. Areas of emphasis include antimicrobial prophylaxis, debridement of devitalized tissue, topical antimicrobial therapy, and optimal time to wound coverage. This evidence-based medicine review was produced to support the Guidelines for the Prevention of Infections Associated With Combat-Related Injuries: 2011 Update contained in this supplement of Journal of Trauma.

Use of bilirubin as a marker of adherence to atazanavir-based antiretroviral therapy

We retrospectively reviewed 134 patients to evaluate atazanavir-related bilirubin elevation as an adherence marker. Using a 2 log reduction or undetectable viral load as a marker for suppression, the median bilirubin increase at first follow-up was 1.3 (0.7–2.2), versus 0.2 (−0.05–0.65) for those not suppressed. An increase in bilirubin of more than 0.4 mg/dl correctly classified 81% of patients as having successful treatment response (sensitivity 87%, specificity 63%), suggesting that bilirubin is a good adherence marker.