A case of Gaucher disease Type 2 due to compound heterozygous mutations in <italic>GBA</italic> gene

Abstract

This study aimed to explore the clinical features and diagnostic strategy of Gaucher disease type 2. The female proband was hospitalized at the age of 13-month-old because of malnutrition and psychomotor regression. She presented “snoring from throat and profuse sputum” after birth and was suspected as “laryngeal stridor”. Malnutrition was observed because of failure to thrive from the age of 6 months. Since the age of 9 months, she presented with mental and motor regression. Rehabilitation training was not effective. When she was 13 months old, splenomegaly, anemia, thrombopenia, and convulsion were noticed. The glucocerebrosidase (GBA) activity of her fresh peripheral leucocytes was significantly decreased (0.4 nmol g−1 min−1, normal control 2.63–25.6 nmol g−1 min−1), while the activity of chitotriosidase was increased greatly (54000.5 nmol L−1 min−1, normal control 0–25145 nmol L−1 min−1). In her GBA gene, two pathogenic compound heterozygous mutations, c.703T>C (p.S235P) and c.1205A>G (p.Y402C), were detected by target genomic DNA capture for next generation sequencing method and validated by Sanger sequencing method. Each parent carried one mutation. The results confirmed the diagnosis of Gaucher disease type 2. Unfortunately, the girl died of asphyxia at the age of 16 months due to milk choking at home. Gaucher disease is a disorder of inborn error of metabolism inherited as autosomal recessive mode due to GBA mutations. Type 2 is the rare type of the disease with poor prognosis. In this study, the girl with occult onset had experienced difficult diagnostic process. Analysis of lysosomal enzyme activities and gene studies are keys for the diagnosis.