MRI, CT and histopathological findings in a cat with hypovitaminosis A

Abstract

An adult, male, domestic longhair cat was evaluated for chronic progressive visual impairment and lethargy. Neurological abnormalities localised to the cerebellum/central vestibular system, and optic chiasm/retinas and/or optic nerves were present on clinical examination. MRI and CT studies showed diffuse hyperostosis with thickening of the calvarium and tentorium cerebelli causing compression and distortion of the brain. Biochemical testing showed low plasma retinol levels at 0.1 μmol/l (0.86–2.2). Postmortem examination showed reduction in volume of the frontal lobes secondary to diffuse skull hyperostosis. Microscopically, there were mild white matter spongiosis affecting the corona radiata and optic nerves and multiple small plaque‐like thickening of the meninges. This is the first case report to provide a comprehensive clinical, diagnostic imaging and pathological details of hypovitaminosis A in a cat.

Pet Wellness and Vitamin A: A Narrative Overview

“…Oxidative damage to DNA, proteins, and lipids is widely recognized as a significant factor contributing to aging and the development of various chronic diseases in cats and dogs [145]. Vitamin A plays a vital role as a systemic antioxidant, impacting various biological processes in animals, including pets [4,146]. Retinol possesses direct antioxidant properties due to its hydrophobic polyene chains, allowing it to quench singlet oxygen and neutralize radicals [147].…”

“…Vitamin A deficiency can arise in pets due to various factors, encompassing inadequate dietary intake, compromised absorption, or increased metabolic demands [146,163,164]. Pets consuming diets deficient in vitamin A or experiencing gastrointestinal disorders such as intestinal fat malabsorption are particularly susceptible.…”

“…One of the primary physiological roles of vitamin A involves maintaining the optimal visual function. Consequently, the felines and canines deficient in this vitamin may manifest symptoms such as nyctalopia, reduced vision in low light, conjunctivitis, xerosis with keratitis and corneal neovascularization, photophobia, mydriasis in normal lighting, delayed pupillary light reflex, progressive retinal cell degeneration, cataract formation, or even complete blindness in severe cases [19,27,146]. Additionally, common neurological manifestations of progressive vitamin A deficiency include an altered mental state, seizures, nystagmus, ataxia, kyphosis, hyperesthesia, muscle wasting, nerve degeneration, and impaired nerve conduction [32,146,166].…”