[Measurement of thiamine concentration in the cat using high pressure liquid chromatography].

Objective: Thiamine deficiency in cats frequently leads to a dysfunction of the central nervous system including vestibular signs with fatal outcome in untreated cases. The aim of the present study was to directly measure thiamine concentrations using high pressure liquid chromatography (HPLC) in feline blood samples and to evaluate values in healthy and diseased cats.
Material and Methods: Blood samples (1 ml EDTA-whole blood) from 193 cats were analysed for total thiamine and thiamine diphosphate using HPLC. For the interpretation of the results cats were retrospectively assigned to six groups: A) healthy cats, B) cats with diseases of the gastrointestinal tract, C) cats with different traumas not affecting the gastrointestinal tract, D) cats with inappetence, cats with central vestibular signs and normal (E) or low values of thiamine (F), respectively.
Results: In animals of group F no obvious cause for the vestibular signs was found and spontaneous recovery after thiamine application occurred in three cats. Therefore thiamine deficiency was a highly likely clinical diagnosis. Total thiamine concentration (mean 48.2 µg/l, standard deviation ± 22.6) of group F significantly differered from the other groups (group A-D: p<0.01, group E: p<0.001). Comparable results were obtained for thiamine diphosphate. However, low total thiamine values were also found in cats with inappetence without any neurological signs.
Conclusion and Clinical Relevance: In the present study a method for direct measurement of thiamine formerly established for ruminants was evaluated for cats. A more accurate and objective clinical diagnosis of thiamine deficiency is feasible in cats with values less than 50 µg/l and typical clinical signs. In animals with values of total thiamine levels between 50-70 µg/l a prophylactic substitution of thiamine can be discussed.