Different organic acid patterns in urine and in cerebrospinal fluid in a patient with biotinidase deficiency

Multiple carboxylase deficiency (MCD) is characterized by decreased activities of the biotin-dependent carboxylases and a specific urinary organic acid pattern. The early-onset form is due to a defect of holocarboxylase-synthetase while deficient biotinidase activity leads to the late-onset form. Both forms are responsive to administration of biotin in pharmacological dosage. The authors report preliminary results of original studies carried out on the cerebrospinal fluid (CSF) of a new case of biotinidase-deficient MCD.