Diagnosis, treatment and genetic analysis of an elderly patient with Gaucher's disease characterized by marked multiple bone destruction.

Gaucher's disease is a rare autosomal recessive genetic disease. Due to the decrease or lack of glucocerebrosidase () activity in lysosome caused by the mutation of gene, its substrate glucocerebroside is detained in lysosome, resulting in clinical manifestations of liver, spleen, kidney, bone, hematopoietic system and even nervous system involvement. Here, we report a case of elderly patient presenting marked multiple bone destruction, with childhood medical history of splenectomy and "osteomyelitis". The patient has a significantly enlarged liver, accompanied by anemia, thrombocytopenia and osteopenia. Laboratory studies show this patient has low blood GBA activity and high glucosyl sphingosine level and increased chitotriosidase activity. Genetic testing revealed a homozygous missense variant NM_001005741.2 c.770A>G (p.Asp257Gly) in the patient's gene. After 6 months of enzyme replacement therapy, the patient's platelets returned to normal, anemia improved, and liver volume decreased. Further detections show that the mother and brothers of the patient have heterozygous mutations at this locus, which is consistent with Mendelian inheritance law. Although this variant has not been reported in literatures or database, both clinical manifestations, characteristics of enzymology and biomarkers, and the effect of enzyme replacement therapy support the diagnosis of Gaucher's disease. The Asp257Gly variant is therefore assessed as a clinical pathogenic variant. This study expands the spectrum of the gene variants. The diagnosis and treatment process of this case also provide reference for the early identification, diagnosis and early treatment of this kind of patients.