Determination of extended-spectrum β-lactamase-producing Klebsiella pneumoniae isolated from horses with respiratory manifestation

Abstract

Background and Aim: The World Health Organization considers multidrug-resistant (MDR) Klebsiella pneumoniae a major global threat. Horses harbor commensal isolates of this bacterial species and potentially serve as reservoirs for human MDR bacteria. This study investigated antimicrobial resistance in horses caused by extended-spectrum β-lactamase (ESBL)-producing K. pneumoniae. Materials and Methods: One hundred fifty-nine nasal swab samples were collected from horses with respiratory distress not treated with cefotaxime and erythromycin. Biochemical and serological identification was performed on all samples. Polymerase chain reaction (PCR) was used to detect 16S-23S ITS, mucoviscosity-associated gene (magA), uridine diphosphate galacturonate 4-epimerase gene (uge), and iron uptake system gene (kfu), blaTEM, blaSHV, and blaCTX genes. Sequence analysis and phylogenetic relatedness of randomly selected K. pneumoniae isolates carrying the blaTEM gene were performed. Results: Ten isolates of Klebsiella spp. were obtained from 159 samples, with an incidence of 6.28% (10 of 159). Based on biochemical and serological identification, K. pneumoniae was detected in 4.4% (7 of 159) of the samples. Using PCR, all tested K. pneumoniae isolates (n=7) carried the 16S-23S ITS gene. By contrast, no isolates carried magA, uge, and kfu genes. The blaTEM gene was detected in all test isolates. Moreover, all isolates did not harbor the blaSHV or blaCTX gene. Sequence analysis and phylogenetic relatedness reported that the maximum likelihood unrooted tree generated indicated the clustering of the test isolate with the other Gram-negative isolate blaTEM. Finally, the sequence distance of the blaTEM gene of the test isolate (generated by Lasergene) showed an identity range of 98.4-100% with the blaTEM gene of the different test isolates. Conclusion: The misuse of antimicrobials and insufficient veterinary services might help generate a population of ESBL-producing K. pneumoniae in equines and humans, representing a public health risk.

Antimicrobial Resistance and Extended-Spectrum Beta-Lactamase Genes in Enterobacterales, Pseudomonas and Acinetobacter Isolates from the Uterus of Healthy Mares

“…were reported in mares with fertility problems [ 62 ] in chronic endometritis and in those without response to antibiotic treatments [ 63 , 64 ]. On the other hand, Klebsiella pneumoniae has been frequently found in respiratory and digestive conditions in horses [ 65 , 66 ]. Enterococcus spp.…”

“…Likewise, the use of broad-spectrum cephalosporins could be a selection factor for bacteria with ESBL. Generally, the resistance genes that code for the expression of this ESBL phenotype, such as bla CTX-M, bla SHV , bla TEM , and bla CTX-M , are in plasmids or integron-type structures, which would facilitate horizontal gene transfer [ 30 , 40 , 66 , 87 , 88 , 89 , 90 ].…”