Aminoacylase 1 deficiency: the first Czech patient

Background: aminoacylase 1 (ACY1D) deficiency (MIM 609924) is a rare metabolic disorder characterized by increased urinary excretion of N-acetylated amino acids (serine, glutamic acid, alanine, methionine, glycine, leucine and valine). The disorder is inherited in an autosomal recessive manner, the ACY1 gene (104620.0001) is located in the 3p21.2 region. So far, about 20 patients have been detected in the world. Case report: Our patient was monitored by a neurologist since infancy for hypotonia, retardation of verticalization, and retardation of the expressive component of speech. For tics and childhood autism under the care of a psychiatrist. The patient suffers from bizarre, purposeless movements, does not establish social and verbal contact, is profoundly autistic, only rarely makes a sound. His condition is assessed as severe mental retardation (IQ 30). Results: Hearing examination (BERA) confirmed moderate perceptual deafness. MRI of the brain: random multiple foci of demyelinating character in the white matter. Profile of organic acids in urine: increased excretion of N-acetyl-alanine (27 mg/gKr), N-acetyl-glycine (23 mg/gKr), N-acetyl-methionine (78 mg/gKr), N-acetyl-glutamate (45 mg/gKr) and N-acetyl-valine (12 mg/gKr), which are not detected in urine under physiological conditions. The finding led to the suspicion of a possible deficiency of the ACY1D enzyme. DNA analysis of the ACY1 gene: the sequence variant NM_000666.2, c.1057C>T p.(Arg353Cys) was found in the homozygous state, which is the most frequently described pathogenic sequence variant for ACY1D. Conclusion: to date, most probands with ACY1D have been described in connection with children who underwent selective metabolic screening for psychomotor developmental delay and a history of seizures. The prognosis of patients remains unclear. The causal treatment is unknown.