A 2015 review discusses treatment strategies for management of nonfermenter infections, including Burkholderia cepacia complex (Bcc). While discussions were limited, it was noted that minocycline and tigecycline had a susceptibility rate between 5.5 and 44.4%. Therefore, a variable activity is observed. However, tigecycline has poor activity due to drug efflux, so recommendations are limited to minocycline as a second-line or combination agent. [1]
A 2021 study analyzed the susceptibility of minocycline against clinically significant gram-negative pathogens, including Burkholderia spp., in samples collected from the United States and Europe. Minocycline susceptibility was shown to be good overall, though susceptibility towards Burkholderia ssp. Was on the lower end (86.8%) compared to other pathogens. MIC50 was 2 mg/L and MIC 90 was 8 mg/L. Note that the majority of Burkholderia ssp. samples were the Bcc which reported a susceptibility rate of 86.3% in isolation to minocycline. [2]
A 2019 in vitro study evaluated the activity of minocycline against the Bcc, based on the SENTRY Antimicrobial Surveillance Program. Minocycline was found to be effective against the majority of Bcc as 88.1% of the tested bacterial strains were inhibited by minocycline at a concentration of 4 mcg/mL or lower. The MIC50 was 2 mcg/mL, and the MIC90 was 8 mcg/mL. Therefore, minocycline was considered an effective treatment option, although resistance has been observed. [3]
A 2000 publication explored multiple combination bactericidal antibiotic testing for patients with cystic fibrosis infected with Burkholderia cepacia. Given the significant resistance of B. cepacia strains to standard antibacterial treatments, the research aimed to evaluate in vitro the effectiveness of various antibiotic combinations. The investigation included 119 multi-drug-resistant isolates and assessed the bactericidal activity of 10 to 15 antimicrobial agents in 225 single, double, and triple antibiotic combinations. Findings highlighted that while 50% of isolates were resistant to all single antibiotics tested, each displayed susceptibility to at least one triple-drug combination. A double antibiotic combination with meropenem and minocycline was bactericidal against 76% of isolates. Triple combinations containing tobramycin and meropenem proved most effective, with bactericidal activity against 81% to 93% of the isolates. [4]
The 2022 article presented a retrospective chart review that involved 44 patients who developed Bcc infections at non-respiratory sites. These patients were admitted between June 2005 and February 2020. Data collection focused on the epidemiological background, associated risk factors, antibiotic regimens employed, and susceptibilities of the Bcc isolates. The primary sites of infection included bacteremia (38.6%), followed by skin and soft tissue infections (36.4%) and vertebral osteomyelitis (18.2%). The majority of the Bcc isolates demonstrated susceptibility to ceftazidime and carbapenems, with trimethoprim-sulfamethoxazole (TMP-SMX) also showing effectiveness. Directed antibiotic therapy based on susceptibility results led to favorable clinical outcomes, highlighting the effectiveness of tailored treatment strategies. One patient in this review received minocycline, but the details of their infection type and disposition were not provided. [5]