Infections in combat casualties during Operations Iraqi and Enduring Freedom

BACKGROUND: Infections are a common acute and chronic complication of combat-related injuries; however, no systematic attempt to assess infections associated with US combat-related injuries occurring in Iraq and Afghanistan has been conducted. The Joint Theater Trauma Registry (JTTR) has been established to collect injury specific medical data from casualties in Iraq and Afghanistan. METHODS: We reviewed the JTTR for the identification of infectious complications (IC) using International Classification of Diseases, 9th Revision (ICD-9) coding during two phases of the wars, before and after the end of the major ground operations in Iraq (19 March-May 31, 2003 and June 1, 2003-December 31, 2006). ICD-9 codes were combined into two categories; anatomic or clinical syndrome and pathogen. An IC was defined as the presence of ICD-9 codes that included both anatomic or clinical syndrome and a pathogen. RESULTS: There were 425 patients evaluated in phase I and 684 in phase II with approximately one third having an IC. The most common anatomic or clinical syndrome codes were skin or wound followed by lung, and the most common pathogen code was gram-negative bacteria. The site of injury had varying rates of IC: spine or back (53%), head or neck (44%), torso (43%), and extremity (35%). Injury Severity Score and certain mechanisms of injury (explosive device, bomb, and landmine) were associated with an IC on multivariate analysis (p < 0.01). CONCLUSION: Infections are common after combat-related injuries. Although the JTTR can provide general information regarding infections, improved data capture and more specific clinical information is necessary to improve overall combat-related injury infection care.