Faculty of Veterinary Medicine University of Zagreb
Abstract
Verocytotoxin-producing Escherichia coli (VTEC) O157:H7 is a predominant cause of haemorrhagic colitis (HC) and haemolytic uraemic syndrome (HUS) in humans. To assess the role of dogs as a possible source of transmission of VTEC O157:H7 to humans, the faeces of diarrhoeic (31) and non-diarrhoeic (63) dogs were examined for the presence of the organism. Escherichia coli O157:H7 was isolated from 22 (23.4%) out of 94 samples examined. The organism was detected in 5 (16.1%) out of 31 diarrhoeic faeces and 17 (26.9%) out of 63 non-diarrhoeic faeces, but the difference was not statistically significant (P>0.05). All the E. coli O157:H7 isolates produced one or both of verocytotoxin 1 and 2 (VT1 and VT2). Verocytotoxin 1 (VT1) was detected in 10 (45.5%) out of 22 isolates, VT2 in 8 (36.4%), while both toxin types were detected in four (18.2%) isolates. Sixteen (72.7%) out of 22 isolates were resistant to at least three antimicrobials from different classes, while 18 distinct antimicrobial resistance patterns were observed among the isolates. The isolates showed resistance to ampicillin (86.4%), chloramphenicol (36.4%), ciprofloxacin (4.5%), gentamicin (18.2%), kanamycin (68.2%), nalidixic acid (22.7%), neomycin (40.9%), norfl oxacin (9.1%), streptomycin (63.6%), sulphamethoxazole/trimethoprim (63.6%) and tetracycline (77.3%). The present study showed that diarrhoeic and non-diarrhoeic dogs may serve as potential sources of multi-drug resistant VTEC O157:H7 transmissible to humans.Verotoksični sojevi bakterije Escherichia coli (VTEC) O157:H7 pretežito uzrokuju hemoragijski kolitis (HC) i hemolitičko-uremijski sindrom (HUS) u ljudi. Radi procjene uloge pasa kao mogućeg izvora prijenosa VTEC O157:H7 na ljude, pretraženi su uzorci njihova proljeva (31) i normalno formiranog fecesa (63) na prisutnost te bakterije. Escherichia coli O157:H7 bila je izdvojena iz 22 (23,4%) od 94 pretražena uzorka. Bila je dokazana u 5 (16,1%) od 31 uzorka proljeva i 17 (26,9%) od 63 uzorka normalno formiranog izmeta. Nije bila ustanovljena statistički značajna razlika (P>0,05). Svi izolati bakterije E. coli O157:H7 proizvodili su jedan ili oba verotoksina: 1 i 2 (VT1 i VT2). Verotoksin 1 bio je dokazan u 10 (45,5%) od 22 izolata, VT2 u osam (36,4%), dok su oba tipa toksina bila dokazana u četiri (18,2%) izolata. Šesnaest (72,7%) od 22 izolata bilo je otporno na najmanje tri antimikrobne tvari različitih skupina. Među izolatima je bilo ustanovljeno 18 različitih obrazaca otpornosti na antimikrobne tvari. Izolati su pokazivali otpornost na ampicilin (86,4%), kloramfenikol (36,4%), ciprofl oksacin (4,5%), gentamicin (18,2%), kanamicin (68,2%), nalidiksičnu kiselinu (22,7%), neomicin (40,9%), norfl oksacin (9,1%), streptomicin (63,6%), sulfametoksazol/trimetoprim (63,6%) i tetraciklin (77,3%). Istraživanje je pokazalo da psi s proljevom i bez proljeva mogu biti izvor multiplorezistentne VTEC O157:H7 za ljude
