FIP – a disease full of curiosities

It is with a sense of excitement and humility that I address this to you. In this issue of the Journal of Feline Medicine and Surgery, I am proud to share with you 45 years of discoveries and attempts to understand the secrets of the puzzling condition we call feline infectious peritonitis (FIP). Dr Niels Pedersen, of the University of California, Davis, possibly the most prolific and prominent researcher in this field, approached us with an entire chapter on FIP. We are thrilled and honoured to provide the platform he chose to use to share this work with the aelurophilic veterinary community.

‘ A review of feline infectious peritonitis virus infection: 1963–2008 ’ appraises all of the work done by esteemed virologists and infectious disease specialists in veterinary medicine. Pedersen presents the history of this fascinating disease. In a very nice section he writes about the causative agent, presenting the evidence for an intriguing concept: FIP, while an infectious condition, isn't caused by a consistently specific virus – but rather mutation of a relatively benign one under appropriate conditions. What a bizarre virus that rarely spreads horizontally yet is pathogenic when inoculated in a research setting.

He summarizes not only the clinical presentations we are well familiar with, but also some that I had never heard of. It seems logical that cats can present initially with the dry form and, as they decompensate, develop effusions, but I was not aware that the reverse is possible as well. Cats with the wet form may mount enough of a cell-mediated response that they transform the presentation from effusive to granulomatous. Dry FIP has been reported mimicking myeloproliferative disease. Patients with FIP can have monoclonal gammopathies. And he slips in many other interesting facts: deaths from FIP are more common in the fall than in the winter months.

There is so much to read and engage with! You may choose to read it in sections. The images illustrate well. I hope I have piqued your curiosity. You will not be disappointed. This is a state of the art reference that you will undoubtedly want to hold on to. And, please remember, Dr Pedersen, a veritable guru in the feline infectious disease world, wanted you to be the recipient of this article.

Enjoy!