An investigation of the relationship between carriage of Leptospira and kidney disease in cats

  • Alix Longhurst

Student thesis: Master's ThesisMaster of Science (MSc)


The aim of this study was to investigate Leptospira as a possible aetiology of chronic kidney disease (CKD), as well as investigating the relationship between demographic, haematological, biochemical, urinary and other variables, with leptospiral infection, in cats.

In this retrospective study, whole blood samples of 158 cats of the feline population of Langford Vets, Bristol, between September 2016 and October 2017, were analysed using a real-time polymerase chain reaction assay (qPCR) targeting the lipL32 gene, present in pathogenic Leptospira.

When analysing the relationship between CKD and leptospiral positivity, 69 cats were excluded due to having existing conditions known or suspected to cause CKD. Of the remaining 89 cats, 2/33 (6.06%) of ‘CKD’ cats and 6/56 (10.71%) of ‘non-CKD’ cats were deemed leptospiral positive by PCR. There was found to be no significant association between CKD and leptospiral positivity.

All cats were included (n=158) when analysing the relationship between other variables and leptospiral positivity. 24/158 (15.19%) cats were deemed leptospiral positive. Statistical analyses revealed that leptospiral positive cats had significantly higher basophil and lymphocyte counts, as well as higher serum alanine aminotransferase. Leptospiral positivity was also significantly associated with AKI, current urolithiasis/nephrolithiasis, eosinophilia and lymphocytosis and biochemical hyperthyroidism. A negative correlation was found with age, abnormally low total protein and biochemical hypothyroidism.

Although, this study failed to demonstrate an association with leptospiral positivity and CKD, it was associated with AKI and younger cats. Younger cats may be more susceptible to infection by the bacterium, before an effective immune response is elicited, which then adapts to, and prevents, future infection. This initial infection may cause AKI and the damage caused later progresses into CKD as a cat gets older, despite the absence of active leptospiraemia by this point. Therefore, leptospiral infection may still be of aetiological relevance to CKD in the cats.
Date of Award23 Jan 2019
Original languageEnglish
Awarding Institution
  • The University of Bristol
SupervisorTristan A Cogan (Supervisor) & Andrea Jeffery (Supervisor)

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