Doxycycline-resistant Enterobactereaceae isolated from clinical infections pets in Argentina.

RUMI MARÍA VALERIA; NUSKE EZEQUIEL; MAS JAVIER; GUTKIND GABRIEL; DI CONZA JOSÉ

Chicago

Congreso; ASM Microbe 2020; 2020

Doxycycline (DOX) is a broad spectrum antibiotic that is a member of the tetracycline family. It is used to treat different bacterial and parasitic infections in human and veterinary medicine. DOX is a first-line drug in some countries for the treatment of respiratory tract disease in dogs and cats. In recent times, the increase in cases of ehrlichiosis, some without confirmed diagnosis, encouraged a growth in the prescription of DOX in prolonged treatments. The aim of this study was to detect DOX resistant Enterobacteriaceae isolated from pets, and evaluate the association with extended spectrum β-lactamases (ESBL) and/or multidrug-resistant (MDR). A total of 219 Enterobacteriaceae were isolated from clinical infections during 2014-2018 from Argentina. Identification was done by MALDI-TOF MS. Resistance was determined by the disk diffusion method (CLSI 2018): ampicillin, amoxicillin-clavulanic, cefotaxime, ceftazidime, cefoxitin, imipenem , meropenem , cefovecin , cefepime , gentamicin , amikacin , trimethoprim-sulfamethoxazole , nalidixic acid , ciprofloxacin , levofloxacin , enrofloxacin , nitrofurantoin , DOX and colistin (COL, by COL-spot). MDR was considered when the isolates were resistant to three or more antibiotics of different families. Screening for extended spectrum β-lactamases (ESBL) production were conducted by double disk synergy test. 92 out of 219 (42%, CI95: [35%, 47%]) isolates were DOX resistant (R). This profile were detected in 66/157 (42%, CI95: [34%, 50%]) E. coli; 19/32 (59%, CI95: [41%, 76%]) K. pneumoniae; 7/30 (23%, CI95: [10%, 42%]) Enterobacter spp. (26/30 E. cloacae). In this study, 132/219 (60%, CI95: [53%, 67%]) Enterobacteriaceae were MDR, of them 89/132 (67%, CI95: [59%, 75%]) DOX-R vs 43/132 (33%, CI95: [25%, 41%]) DOX sensitive (S). While for 105/219 (48%, CI95: [41%, 55%]) ESBL producers were 61/105 (58%, CI95: [48%, 68%]) DOX-R and 44/105 (42%, CI95: [32%, 52%]) DOX-S. More than one quarter of the strains were ESBL, MDR and DOX-R (60/219: 27%). The strongest association was detected between MDR and DOX-R with an Odds Ratio (OR) of 57, while association between ESBL and DOX-R had an OR of 9.Variations in antibiotic susceptibility in different bacterial populations make knowledge of local resistance patterns vital. Thus, the alarming emergence of ESBL and MDR isolates in pets, DOX may be a good therapeutic option, preserving other critical antibiotics such as carbapenems and COL