Critical review of a series of Acinetobacter spp surgical and blood stream infections at a rural hospital in the Appalachian region

Authors:
Saron Araya, Pathya Kunthy, Sridha Gona, Aaron George, Hugo Bonatti

Body of Abstract:
Background: Acinetobacter spp are opportunistic non-fermentative Gram-negative rods, which are found in soil and water. The organisms are associated with surgical, urinary tract, respiratory tract and blood stream infections, which may be difficult to treat due to natural resistance against many antibiotics.

Methods: Our institutional database was searched for all infections caused by Acinetobacter spp during a 4-year period.

Results: In total 64 isolates in 58 patients were identified. Median age of the 38 males and 26 females was 62.6 (11.3-88.2) years. Rates of comorbid conditions were DM 33%, hypertension 38%, hyperlipidemia 31%, COPD 10%, CAD 16%, and malignancies 7%. 37% of individuals were obese and 29% active smokers. Acinetobacter baumannii was isolated in 69%, lwoffii in 17%, radioresistens 6%, ursinglis 3% and calcoaceticus, junii and species 2% each. Demographic, clinical, and microbiology data are shown in table 1. Bacterial growth pattern based on streak appearance for surgical specimens was reported light in 48%, moderate in 7% and heavy in 45%; 72% of infections were polymicrobial with staphylococci in 32%, streptococci in 13%, Gram-negative rods in 34%, anaerobes in 19% and yeast in 1% as co-pathogens. Blood cultures accounted for 34%, drainage fluids/tissue specimens for 31% and wound cultures for 33% of specimens, 12% came from drained abscesses. Lower extremity soft tissue infections were the most common manifestation with 55%, the trunk was involved in 10% and upper extremities in 2%; in 9% intraabdominal infections were diagnosed. The majority of blood cultures were sent by emergency department and 50% of the surgical specimens were submitted by podiatry. Treatment for surgical infection included incision and drainage, debridement and amputation as indicated together with antibiotics according to sensitivity testing considering the high rate of mixed infections.

Conclusion: Acinetobacter spp infections in our rural setting were caused by a surprising variety of different strains. Clinically, one third of cases included bacteremia. The most common infection in this series was diabetic foot syndrome. The majority of these infections were treated successfully and 91% of patients were alive after a 2 year follow up.