Antimicrobial resistance among Haemophilus influenzae isolates responsible for lower respiratory tract infections in Poland, 2005 –2019

AbstractHaemophilus influenzae is a human-specific pathogen responsible for respiratory tract infections, meningitis, and sepsis. The study aimed to characterize antibiotic resistance inH. influenzae strains isolated from patients with lower respiratory tract infections over 15  years in Poland. The minimum inhibitory concentrations (MICs) of clinically relevant antibiotics were determined by broth microdilution method. Screening for beta-lactam resistance was performed in all isolates following EUCAST recommendation. Finally, relevant changes in penicillin-binding prote in 3 (PBP3) were detected by PCR screening. Of the 1481 isolates collected between 2005 and 2019, 12.6%, 0.2%, 17.1%, and 0.2% were resistant to ampicillin, amoxicillin/clavulanate, cefuroxime, and ceftriaxone, respectively. Among them, 74.4% (1102/1481) of isolates were categorized as BLNAS (β-lac tamase negative, ampicillin-susceptible), 13.0% (192/1481) as BLNAS with modified PBP3 (mutations inftsI gene), 2.6% (39/1481) as BLNAR ( β-lactamase negative, ampicillin-resistant), and 0.2% had PBP3 modifications typical for high-BLNAR. Production of β-lactamase characterized 9.7% of isolates (8.6% BLPAR-β-lactamase-positive, ampicillin-resistant, and 1.1% BLPACR-β-lactamase-positive, amoxicillin-clavulanate resistant). Three is olates with PBP3 modifications typical for high-BLNAR proved resistant to ceftriaxone (MIC >  0.125 mg/L). Resistance to ciprofloxacin, chloramphenicol, tetracycline, and t...
Source: European Journal of Clinical Microbiology and Infectious Diseases - Category: Microbiology Source Type: research