Antimicrobial resistance profiles of human Brucella melitensis isolates in three different microdilution broths: the first multicentre study in Bosnia and Herzegovina.

OBJECTIVES: Brucellosis is a ubiquitous emergent bacterial zoonotic disease causing significant human morbidity in Bosnia and Herzegovina. So far, a high rate of resistant Brucella has been found worldwide. This study prospectively analysed the rates of resistance among human Brucella melitensis strains isolated in Bosnia and Herzegovina. METHODS: This study included 108 B. melitensis isolates from 209 patients diagnosed at five medical centres in Bosnia and Herzegovina. The resistance profiles of the B. melitensis isolates for the 13 most commonly used antimicrobials were studied in standard Brucella broth (BB) and cation-adjusted Mueller-Hinton broth (CAMHB) supplemented with 4% lysed horse blood or 5% defibrinated sheep blood. RESULTS: Of the 209 patients, B. melitensis blood cultures were positive for 111 (53.1%). Among the 108 isolates investigated, 91 (84.3%) were resistant to trimethoprim-sulfamethoxazole on BB, but not on either CAMHB. Nearly all isolates (>90%) were resistant to azithromycin on BB and both CAMHBs. CONCLUSION: We observed a high rate of B. melitensis resistance to azithromycin. The high rate of resistance to trimethoprim-sulfamethoxazole that we observed was related to BB, so an alternative broth should be used, such as the enriched CAMHBs in this study, for evaluating resistance to trimethoprim-sulfamethoxazole. Whole-genome sequencing studies are needed to understand the development of antimicrobial resistance in B. melitensis strains isolated from humans.

The Importance of Acinetobacter Species in the Hospital Environment.

INTRODUCTION: Acinetobacter species is associated with health care associated infections especially in patients on respiratory therapy equipment and indwelling catheters. They are becoming increasingly drug resistant. The knowledge of the prevalence and pattern of antimicrobial susceptibility pattern of Acinetobacter spp. is important. AIMS: The study is undertaken to estimate the prevalence rate, risk factors and antimicrobial resistance pattern of isolates. in Acinetobacter spp. from various clinical samples. MATERIAL AND METHODS: The isolates of Acinetobacter species obtained from various clinical specimen. Specimens were processed by standard microbiological techniques. Antimicrobial sensitivity tests of the Acinetobacter isolates were done by modified Kirby-Bauer disc diffusion method. RESULTS: Out of 622 isolates, 399 isolates were from inpatients (62,18%) and 223 were from outpatients (37,82%). More than 90% of isolates displayed resistance to ampicillin, amoxicillin-clavulanic acid, ceftazidime, caftriaxon and amikacin. Resistance to gentamicin, co-trimoxazole and ciprofloxacin were also common. Least resistance was seen to piperacillin-tazobactam and imipenem. A total of 125 Acinetobacter isolates were analyzed, out of which 78.4 % were multi-drug resistant (MDR). Of these MDR isolates, 17.24% were pan-resistant. A. baumannii was the most common species responsible for wound infection (84,8%), pneumonia(96,15%), abscess (72.7%), urinary tract infection (85,7%) and septicemia(89,5%). CONCLUSION: Multi-drug resistant Acinetobacter has emerged as an important nosocomial pathogen. Antibiotic susceptibility testing is critical in the treatment of infections caused by Acinetobacter. Continued surveillance of prevalent organisms in ICUs, combined with preventive measures remains absolutely essential in efforts to prevent or limit the spread of Acinetobacter infection.