Early detection of OXA-48 producing Klebsiella pneumoniae with the use of rapid antibiotic susceptibility testing.

Rapid antimicrobial susceptibility testing of positive blood cultures can enhance antimicrobial stewardship and patient outcomes. We present a case where OXA-48-producing Klebsiella pneumoniae with low-level carbapenem resistance was suspected 6 h after blood-culture positivity, based on ASTar system (Q-Linea, Sweden) results. OXA-48 carbapenemase presence was confirmed by the OXA-48 K-SeT lateral flow assay (Coris, Belgium) on a short-term subculture. This led to timely therapeutic adjustments. Following this case, we validated the OXA-48 K-SeT and Xpert Carba-R assay (Cepheid, USA) on short-term incubated (6 h) subcultures of positive blood cultures, demonstrating that OXA-48 K-SeT and Xpert Carba-R respectively accurately identified OXA-48 and various (OXA-48, VIM, NDM, KPC, IMP) carbapenemase-producing Enterobacterales (CPE) types. Both assays prove valuable for rapid CPE detection in clinical settings.