Presenter – Sheri Ross DVM PhD DACVIM from the University of California Companion Animal Hemodialysis Unit
The Webinar Vet has once again succeeded in making part two of this veterinary webinar covering the treatment of feline urinary tract infections every bit as interesting and informative as part one. Sheri Ross from the University of California gave us a plethora of advice on how to treat these sometimes stubborn infections in a practical and relevant way.
The choice of antibiotics for treating these infections is key, not only for curing the problem but also to minimise any risk of antimicrobial resistance. Sheri could not stress enough the importance of choosing an appropriate antibiotic based on its efficacy against the causal bacteria and its ability to reach the right site at the necessary concentrations of four times that of the MIC. It is also paramount that owner compliance is achieved to ensure the correct dose is given over the correct duration.
Sheri agrees in cases of simple cystourethritis where infection is present, treatment with an appropriate antibiotic prior to obtaining a culture and sensitivity could be considered. First line antibiotics such as amoxicillin are a sensible choice but more aggressive antibiotics should always be reserved and used only after an appropriate culture and sensitivity. However, as stated in Sheri’s previous veterinary webinar, she believes that if a cat has a urinary tract infection there is likely to be underlying complications such as diabetes or chronic kidney disease and these cases should always be investigated further.
A recurrent infection is defined as more than two UTI’s in six months. Underlying causes should be investigated and the presence of a superbug may also be possible. In treating the initial UTI with antibiotics, the normal flora of the bladder can be disrupted and this could lead to the growth of a superbug which may be resistant to the antibiotics being used. Treatment of these recurrent cases involves performing a culture and sensitivity prior to starting treatment and then repeating this 3-5 days after starting therapy. There should be no bacterial growth at this stage if treatment is working but if bacteria are found, the incorrect antibiotic has been chosen and should be altered. A culture is then repeated at 5-7 days post therapy and ideally 1,2,3,6 and 12 months after treatment.
Pyelonephritis should also be considered if LUTD is seen alongside fever and /or anorexia, lethargy, vomiting and pain. Ultrasound and the presence of an active urine sediment and a positive urine culture can all help in making a diagnosis. It is always necessary to ensure there is no ureteral obstruction indicated by ureteral dilation on ultrasound as the kidney can be rapidly and irreversibly damaged in this situation. Cases of pyelonephritis should be treated with fluid therapy, iv antibiotics, followed by oral antibiotics for a 4-6 week period. Fluoroquinolones may be indicated for these cases if there is confirmed bacterial susceptibility on culture.
These two veterinary webinars covering feline urinary tract infections have provided a valuable resource from which to learn how to best diagnose and manage these cases. With antimicrobial resistance on the up, the correct treatment of these cases is all the more important and I would highly recommend this veterinary CPD, it really is an hour well spent.
The Stethoscope (MRCVS)