MRI findings in Neurologic FIP

Feline Infectious Peritonitis (FIP) is the most common infectious disease affecting the central nervous system in cats and is usually fatal. An accurate diagnosis is important to help clinicians to manage owner expectations and avoid unsuccessful treatment. FIP is caused by a virus, FIPV, a mutant of the widespread feline enteric coronavirus (FECV).  These viruses are genetically and serologically indistinguishable which makes ante-mortem diagnosis difficult.

The authors examined the medical records of 24 cats from 5 centers with a diagnosis of neurologic FIP.  All of the animals had been submitted to MRI. The most common clinical signs in the animals included abnormal mentation, tetraparesis, pathologic nystagmus and vestibular ataxia. The authors identified three particular conditions:

• T3-L3 myelopathy without brain involvement;
• Central vestibular syndrome;
• Multifocal CNS disease.

Abnormalities, including contrast enhancement for the meninges and ependyma, ventriculomegaly, syringomyelia and foramen magnum herniation were seen in all of the animals.

The results suggest that MRI, when combined with clinical presentation and other tests, can help clinicians to accurately diagnose FIP before death.  This capability could be helpful in establishing a more precise prognosis and in managing client expectations.

In Crawford, A H et al. “Clinicopathologic Features and Magnetic Resonance Imaging Findings in 24 Cats with Histopathologically Confirmed Neurologic Feline Infectious Peritonitis” Journal of veterinary internal medicine vol. 31,5 (2017): 1477-1486.