Feline hyperesthesia syndrome (FHS) is a well-known but poorly understood disease of cats. It is characterized by a diverse range of clinical signs including tail chasing, biting and licking at the tail and lumbar region, skin rippling, vocalization, wild running and jumping, and other non-specific signs. It has been variously classified as a dermatologic, behavioural, spinal, epileptic, compulsive, or a multitude of other classes of disorder. Clinical signs may be mild, but may also cause severe distress to both cats and owners and may lead to clinically significant self harm. Due to the wide range of clinical manifestations, many treatments have been proposed including steroids, analgesics, vitamins, anticonvulsants, benzodiazepines, and others. The relative efficacy of these treatments has not been well described.
The purpose of this study was to describe a case series of cats with FHS, including diagnostic steps and formulation of a multimodal treatment plan. The study was designed as a retrospective observational study using medical records from two British referral hospitals.
Seven cats were identified in the medical records; all domestic shorthairs, 6 male and 1 female, 5 with outdoor access. Median age was 1 year. Cats exhibited classic clinical signs of hyperesthesia, and received routine CBC and blood chemistries, toxoplasma, FeLV, and FIV testing, MRI of the brain and spinal cord, and CSF analysis. 4 cats underwent electrodiagnostics. These tests showed no cause for clinical signs.
Cats received therapy with a combination of medications as follows: Gabapentin, 6 cats; meloxicam, 4 cats; antibiotics, 4 cats; phenobarbital, 2 cats; prednisolone, 2 cats; topiramate, 2 cats; ciclosporin, clomipramine, fluoxetine, amitriptyline and tramadol, 1 cat each. Improvement was seen in 6 cases; 2 with gabapentin alone, the rest with a combination of gabapentin / ciclosporin / amitriptyline (one cat), gabapentin / prednisolone / phenobarbital (one cat) or gabapentin / topiramate / meloxicam (one cat).
Based on these findings, gabapentin appeared to be the most frequently used an effective monotherapy for FHS, as well as an effective drug in conjunction with other therapies. While skin disease may have played a role in some of the patients, therapy for atopy was no successful in many cases. Anti-epileptic drugs such as phenobarbital and topiramate were not successful in isolation. The authors constructed a flow chart as a protocol to be used in the diagnosis and workup of cats with FHS.
The retrospective nature of the study, combined with the varied treatment and diagnostics plans and the lack of definitive diagnosis place significant limitations on this study. However, it provides some insight into a confusing and not fully understood disease, and gives some groundwork into understanding the response to therapy.
