Clinical signs, MRI features, and outcomes of two cats with thiamine deficiency secondary to diet change

Abstract

Two cats were presented with vestibular signs and seizures. Both cats were diagnosed with thiamine deficiency. The transverse and dorsal T2-weighted magnetic resonance (MR) images revealed the presence of bilateral hyperintense lesions at specific nuclei of the midbrain, cerebellum, and brainstem. After thiamine supplementation, the clinical signs gradually improved. Repeated MR images taken 3 weeks after thiamine supplementation had started showed that the lesions were nearly resolved. This case report describes the clinical and MR findings associated with thiamine deficiency in two cats.

The Role of Thiamine and Effects of Deficiency in Dogs and Cats

“…In dogs and cats, these can include ataxia, paraparesis, nystagmus, delayed pupillary light response and blindness, recumbency, and increasingly poor proprioception, as well as seizures [ 4 , 5 , 9 , 28 , 35 , 38 , 106 , 109 ]. Cats may also exhibit cervical ventroflexion [ 106 , 109 ] and dyspnea [ 9 , 106 ]. Cardiovascular signs during chronic deficiency may include arrhythmias and bradycardia [ 110 ].…”

“…Thiamine deficiency is poorly reflected on routine bloodwork. A complete blood count and serum biochemistry profile may be unremarkable in thiamine-deficient animals, even after prolonged deficiency [ 5 , 7 , 28 , 38 , 109 ]. High concentrations of organic acids that indicate impairment in thiamine metabolism may be used to diagnose thiamine deficiency [ 28 , 29 ].…”

“…Elevated lactate concentrations in urine may occur in dogs with thiamine deficiency [ 28 , 110 ], but these are not always present in cats [ 29 ]. As well, elevated lactate concentrations in plasma and cerebrospinal fluid (CSF) are not always present in dogs during thiamine deficiency [ 100 ], and CSF results can be unremarkable [ 7 , 106 , 109 ]. Blood pyruvate concentrations may be elevated in dogs with thiamine deficiency [ 110 ].…”

“…This may be due to the lack of an established reference range for thiamine status in dogs and cats, as well as poor availability of laboratories that routinely conduct thiamine analyses. Instead, thiamine deficiency in dogs and cats is typically diagnosed based on clinical signs and the presence of risk factors (e.g., unbalanced diet), and diagnosis is confirmed if signs reverse after thiamine supplementation [ 5 , 8 , 28 , 29 , 109 , 111 , 112 ]. An assessment of risk factors for thiamine deficiency should be accompanied by a nutritional assessment, such as the World Small Animal Veterinary Association (WSAVA) nutritional assessment guidelines, to rule out a nutritional cause [ 113 ].…”

Amprolium-induced thiamine deficiency in mice: evaluation of a practical model by oral administration

“…PEM has been described in several regions involving ruminants (APLEY, 2015;BARROS, 2010). However, thiamine deficiency is also important for carnivores (Chastek's palsy) (MOON;KANG;PARK, 2013) and humans (Beriberi, Wernicke's encephalopathy, and Wernicke-Korsakoff syndrome) (NARDONE et al, 2013;VETRENO et al, 2012).…”