Clinical Course and Diagnostic Findings of Biopsy Controlled Presumed Immune-Mediated Polyneuropathy in 70 European Cats

Abstract

There is a paucity of information on the clinical course and outcome of young cats with polyneuropathy. The aim of the study was to describe the clinical features, diagnostic investigations, and outcome of a large cohort of cats with inflammatory polyneuropathy from several European countries. Seventy cats with inflammatory infiltrates in intramuscular nerves and/or peripheral nerve biopsies were retrospectively included. Information from medical records and follow up were acquired via questionnaires filled by veterinary neurologists who had submitted muscle and nerve biopsies (2011–2019). Median age at onset was 10 months (range: 4–120 months). The most common breed was British short hair (25.7%), followed by Domestic short hair (24.3%), Bengal cat (11.4%), Maine Coon (8.6%) and Persian cat (5.7%), and 14 other breeds. Male cats were predominantly affected (64.3%). Clinical signs were weakness (98.6%) and tetraparesis (75.7%) in association with decreased withdrawal reflexes (83.6%) and, less commonly, cranial nerve signs (17.1%), spinal pain/hyperesthesia (12.9%), and micturition/defecation problems (14.3%). Onset was sudden (30.1%) or insidious (69.1%), and an initial progressive phase was reported in 74.3%. Characteristic findings on electrodiagnostic examination were presence of generalized spontaneous electric muscle activity (89.6%), decreased motor nerve conduction velocity (52.3%), abnormal F-wave studies (72.4%), pattern of temporal dispersion (26.1%) and unremarkable sensory tests. The clinical course was mainly described as remittent (49.2%) or remittent-relapsing (34.9%), while stagnation, progressive course or waxing and waning were less frequently reported. Relapses were common and occurred in 35.7% of the cats' population. An overall favorable outcome was reported in 79.4% of patients. In conclusion, young age at the time of diagnosis and sudden onset of clinical signs were significantly associated with recovery (p < 0.05). Clinical and electrodiagnostic features and the remittent-relapsing clinical course resembles juvenile chronic inflammatory demyelinating polyneuropathy (CIDP), as seen in human (children/adolescents), in many aspects.

Serum anti‐GM2 and anti‐GalNAc‐GD1a ganglioside IgG antibodies are biomarkers for immune‐mediated polyneuropathies in cats

“…These changes are consistent with previous reports in the literature and support the presence both of demyelination and axonal loss in IPN-cats. 5,6,16 Conversely, histological examinations conducted on peripheral nerve biopsies taken from IPN-cats show evidence of demyelination and remyelination, less commonly axonal degeneration and regeneration, and variable inflammatory infiltrates. Muscle biopsies from affected cats commonly show a loss of myelinated intramuscular nerve fibres with or without mononuclear infiltrates.…”

Neurolymphomatosis in a cat with diffuse neuromuscular signs including cranial nerve involvement

“…Cranial nerve involvement in cats with (suspected) polyneuropathies is not common. 19,20 In a recent study published of cats with immune-mediated polyneuropathy, 17% of the study population showed signs of cranial nerve involvement. 20 EMG of the limb muscles showed abnormalities consistent with denervation.…”

“…19,20 In a recent study published of cats with immune-mediated polyneuropathy, 17% of the study population showed signs of cranial nerve involvement. 20 EMG of the limb muscles showed abnormalities consistent with denervation. However, EMG abnormalities could not be observed in the masseter and temporalis muscles, which we had expected to be present due to the trigeminal nerve motor deficits (weak masticatory muscle tone).…”

“…With the first‐order neuron arising from the hypothalamus and extending down the spinal cord, the second‐order neuron arising from the first three thoracic spinal cord segments and travelling back through both thorax and cervical region before it synapses at the cranial cervical ganglion and the third‐order neuron travelling from this last ganglion to the eye. Cranial nerve involvement in cats with (suspected) polyneuropathies is not common 19,20 . In a recent study published of cats with immune‐mediated polyneuropathy, 17% of the study population showed signs of cranial nerve involvement 20 …”

Biopsy Characteristics, Subtypes, and Prognostic Features in 107 Cases of Feline Presumed Immune-Mediated Polyneuropathy

“…Recovery was defined as the state in which the cat could walk without assistance and could jump onto objects. Results of patient history, onset of clinical signs, course of the disease, neurological examination, results of the electrophysiological examination, imaging findings including MRI and CT, laboratory workup, and outcome are described by van Renen et al (28).…”