Biogenic amine metabolites and thiamine in cerebrospinal fluid in heredo-degenerative ataxias

Background: The aims of the present study were: i) to measure levels of the dopamine metabolite homovanillic acid (HVA), the serotonin metabolite 5-hy droxindoleacetic acid (5HIAA) and precursor tryptophan, as well as the nora drenaline metabolite 3-methoxy-4-hydroxyphenylethylene glycol (MHPG) and th iamine in the cerebrospinal fluid (CSF) of patients with Friedreich's ataxi a (FA), olivopontocerebellar atrophy (OPCA), and the autosomal recessive sp astic ataxia of Charlevoix-Saguenay (ARSAC), as compared with sex- and age- matched control subjects. Patients and methods: CSF amine related compound levels and thiamine results were compared in 40 FA, 44 OPCA and nine ARSAC patients with those of 94 sex- and age-matched subjects. Neuroimaging (CT s cans and single photon emission computed tomographies i.e. SPECT) were carr ied out in all patients and controls. Genetic studies were conducted on OPC A patients. CSF amine related compounds were measured by high performance l iquid chromatography, whereas CSF thiamine levels were measured by a microb iological method. Results: FA patients had significantly lower CSF HVA, 5HI AA and thiamine values than control patients and a trend for lower MHPG lev els. In OPCA patients, CSF HVA, MHPG and thiamine values were markedly lowe r whereas CSF 5HIAA values showed only a trend towards lower levels; in ARS AC patients only thiamine and HVA CSF values were lower than those in contr ol subjects. Conclusion: After presenting the relationships between neuroch emical findings on one side, the degree of ataxia, the degree of cerebellar atrophy and the SPECT findings on the other, the authors concluded that re placement and neuroprotective clinical trials in these patients would have to include two or three drugs because the neurotransmitter deficiencies are multiple.