Mucolipidosis type IV in the practice of pediatricians and medical geneticists

Abstract

Mucolipidosis type IV is a rare autosomal recessive disease from the group of lysosomal accumulation diseases caused by a malfunction of the cation channel due to mutations in the MCOLN1 gene. The clinical symptom complex includes a combination of neurological symptoms (impaired speech and motor development, spasticity, rigidity), corneal opacity and achlorhydria with iron deficiency anemia. The literature data on this disease and the medical history of a 13-year-old girl who was observed in the Department of Clinical Genetics of the Veltischev Institute are presented. The child had a characteristic clinical picture, including damage to the nervous system: decreased intelligence, muscular dystonia and spasticity, salivation, strabismus, hypoplasia of the corpus callosum; damage to the organ of vision — corneal opacity, cataracts, myopia, photophobia in combination with persistent iron deficiency anemia (apparently due to achlorhydria). The diagnosis was confirmed by the results of DNA diagnostics — a known pathogenic mutation NM_02533.3 was detected in the MCOLN1 gene: c.304C>T (p.Arg102Term) in a homozygous state; in the girl’s mother — in a heterozygous state. A differential diagnosis was made with phenotypically similar diseases, primarily with cerebral palsy, mucopolysaccharidosis, and other types of mucolipidosis. Further medical supervision of the child should be carried out with the obligatory participation of a neurologist, an optometrist, a gastroenterologist, an orthopedist and a nephrologist. Knowledge of the clinical features of pathology ensures more successful medical care with the prevention of complications.