Bacterial and fungal colonisation of peripheral intravenous catheters in dogs and cats.

Objectives: The purposes of this study were to determine the prevalence of intravenous catheter colonisation in a routine clinical setting, to identify pathogens involved and to explore factors associated with an increased risk of colonisation.

Methods: A prospective study of 100 peripherally placed intravenous catheters from 13 cats and 78 dogs was conducted. The distal two-thirds were removed and submitted for bacterial and fungal cultures. Antimicrobial susceptibility of each isolate was determined.

Results: Nineteen peripheral catheters were positive for microbiologic culture from 14 animals. Twenty organisms were isolated among which Staphylococcus species was the most common. Isolates displayed lower levels of resistance against the antimicrobial agents amoxicillin-clavulanate, cephalosporins and gentamicin than against other agents tested. Major risk factors predisposing to catheter-related colonisation included dextrose infusion, duration of catheter placement, local complications and immunosuppressive diseases or drugs.

Clinical Significance: In a routine clinical setting, the prevalence of microbial colonisation of peripheral intravenous catheters is comparable to that found in an intensive care unit. However, consequences on morbidity and mortality rates differ.