Community- and Hospital-Acquired Klebsiella pneumoniae Urinary Tract Infections in Portugal: Virulence and Antibiotic Resistance

Abstract

Klebsiella pneumoniae is a clinically relevant pathogen and a frequent cause of hospital-acquired (HA) and community-acquired (CA) urinary tract infections (UTI). The increased resistance of this pathogen is leading to limited therapeutic options. To investigate the epidemiology, virulence, and antibiotic resistance profile of K. pneumoniae in urinary tract infections, we conducted a multicenter retrospective study for a total of 81 isolates (50 CA-UTI and 31 HA-UTI) in Portugal. The detection and characterization of resistance and virulence determinants were performed by molecular methods (PCR, PCR-based replicon typing, and multilocus sequence typing (MLST)). Out of 50 CA-UTI isolates, six (12.0%) carried β-lactamase enzymes, namely bla_TEM-156 (n = 2), bla_TEM-24 (n = 1), bla_SHV-11 (n = 1), bla_SHV-33 (n = 1), and bla_CTX-M-15 (n = 1). All HA-UTI were extended-spectrum β-lactamase (ESBL) producers and had a multidrug resistant profile as compared to the CA-UTI isolates, which were mainly resistant to ciprofloxacin, levofloxacin, tigecycline, and fosfomycin. In conclusion, in contrast to community-acquired isolates, there is an overlap between virulence and multidrug resistance for hospital-acquired UTI K. pneumoniae pathogens. The study is the first to report different virulence characteristics for hospital and community K. pneumoniae pathogens, despite the production of β-lactamase and even with the presence of CTX-M-15 ESBL, a successful international ST15 clone, which were identified in both settings. This highlights that a focus on genomic surveillance should remain a priority in the hospital environment.

Keywords: Klebsiella pneumoniae; multidrug resistance; urinary tract infections; virulence genes.

Figure 1

Antimicrobial susceptibilities of the K. pneumoniae clinical isolates (n = 81). The isolates were recovered from community-acquired (CA)-urinary tract infection (UTI) and hospital-acquired (HA)-UTI patients. The CA isolates were consecutively collected while the HA isolates were selected from the FFUL collection based on the source of isolation (urine only), beta-lactamase type produced, and within this, by random selection. Legend: AMC, amoxicillin/clavulanic acid; FOX, cefoxitin; CAZ, ceftazidime; CTX, cefotaxime; CIP, ciprofloxacin; LVF, levofloxacin, GM, gentamicin; IMP, imipenem; MER, meropenem; ERT, ertapenem; TIG, tigecycline; FOS, fosfomycin; FFUL, Faculty of Pharmacy University of Lisboa.