Introduction: Acinetobacter baumannii is a non-fermentive Gram-negative cocci-bacillus with multiple resistance genes isolated with increasing frequency in intensive care units.

Methods: Electronic microbiology records were inquired for thermal injury patients with isolation of A. baumannii (AB) from sputum, blood, or wound cultures. Patients were designated as “colonized”(COL) if a single AB culture was obtained and considered “infected” (INF) if AB isolates were obtained from 2 or more sites or at 2 or more time periods. INF patients were then evaluated for whether or not they had been treated with antibiotics for which the isolate was sensitive.

Results: Isolates (N = 8729) from INF (N = 308) demonstrated susceptibility to ciprofloxacin, cefepime, imipenem cilistatin (IC), ampicillin sulbactam (AS), colistin, and tigecycline. Chi-square analysis as “eradicated,” “persisting,”and “failure” for these six antimicrobial agents did not differ (X2 = 5.2873; p >> 0.05). T-test comparison of the 45 COL versus 308 INF demonstrated no difference in age, height, weight, or initial laboratory tests. Day to first A. baumannii culture also did not differ between COL and INF. As expected, total body surface area burn (T = 4.28256; p << 0.05) and length of stay (T = 4.0475; p << 0.05) were greater in INF. All 45 COL survived; however only 207 INF survived (76.9%). T-test analysis of INF survival status noted that non-survivors were older (T = 2.1207; P = 0.03), had larger burns (T = 3.1157; p <<0.05), had lower serum albumin levels (T = 2.0214; p = 0.04), and had positive cultures sooner (T = 2.9108; p << 0.05). For INF, inhalation injury did not predict increased mortality (X2 = 0.5535; p >> 0.05). Stratification by mg/kg dose and renal function of IC and AS demonstrated no difference in eradication, persistence, or failure for doses < 40 mg/kg and < 250 mg/kg and for doses > 40 mg/kg and > 250 mg/kg for IC (X2 = 2.47; P >> 0.5) and AS (X2 = 4.39; P >> 0.05), respectively. Difference in time to eradication and a few other parameters remain to be assessed.

Conclusion: These initial data indicate that the chosen antibiotic and dose had no impact on AB eradication. For these multi-resistant AB INF patients nearly 25% succumbed to infection. Early isolation of AB was associated with increased risk of mortality, as was larger burns, older age, and lower albumin. AB in thermal injury patients was a persisting opportunistic INF with low virulence and high antimicrobial agent resistance for which patients “died with,“ rather than “died of” AB.