Undetectable levels of CSF amyloid-ß peptide in a patient with 17ß-hydroxysteroid dehydrogenase deficiency.

ABSTRACT

17ß-hydroxysteroid dehydrogenase 10 (HSD10) deficiency is a rare X-linked inborn error of isoleucine catabolism. Although this protein has been genetically implicated in Alzheimer's disease pathogenesis, studies of amyloid-ß peptide (Aß) in patients with HSD10 deficiency have not been previously reported. We found, in a severely affected child with HSD10 deficiency, undetectable levels of Aß in the cerebrospinal fluid, together with low expression of brain-derived neurotrophic factor, α-synuclein, and serotonin metabolites. Confirmation of these findings in other patients would help elucidating mechanisms of synaptic dysfunction in this disease, and highlight the role of Aß in both early and late periods of life.