Publication:

Antibiotic resistance in aerobic bacterial isolates from infected diabetic foot ulcers in North Eastern Tanzania: an urgent call to establish a hospital antimicrobial stewardship committee

Background Diabetic foot ulcers (DFU) is among major health problems which impact the socio economic burden globally. We aimed at assessing the susceptibility pattern of antimicrobials in DFU infections among patients admitted in the surgical department at Kilimanjaro Christian Medical Centre (KCMC).

Methods This descriptive cross-sectional study was conducted from September 2018 through March 2019. Pus swabs were collected on the first day of admission by deep wound swabbing after irrigation with normal saline solution. Kirby-Bauer method was done according to the Clinical and Laboratory Standard Institute (CLSI) guidelines.

Results Sixty diabetic ulcer patients had 62 bacterial isolates. Majority of the isolates were gram negative 49/62 (79.03%). The most common isolate was Escherichia coli 15/62 (24.19%) followed by Pseudomonas aeruginosa 14/62 (22.58%), Proteus mirabilis 8/62 (12.9%) and Staphylococcus aureus 5/62 (8.06%). Klebsiella pneumoniae, coagulase negative Staphylococcus, Proteus vulgaris, and Streptococcus pyogenes each contributed 4/62 (6.25%) isolates. Of the 49/62 (79.3%) gram negative isolates, 8/49 (16.33%) were mono resistant, 30/49 (61.22%) were multiresistant, and 11/49 (22.45%) were susceptible. Of the multi-resistant isolates, E. coli 12/15 (80.00%), and P. aeruginosa 7/14 (50.00%) were predominant. A total of 39/62 (62.90%) isolates in patients contributed to poorer outcomes including loss of body part. Patients with ulcers infected by P. aeruginosa 11/39 (28.21%) had the highest number of surgical removal of body parts followed by E. coli 8/39 (20.51%). Gram negative bacteria were highly susceptible to amikacin 91.18%, meropenem 93.33% and imipenem 95.24%. Isolates susceptibility to ceftriaxone was 32%.

Conclusions Amikacin, meropenem and imipenem can be safely used as broad-spectrum antimicrobials in DFU. The standard of care remains culture and sensitivity of isolated microorganisms in combating diabetic foot ulcers infections.