First diagnosis of mucolipidosis type II at the Vietnam National Children’s Hospital
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Abstract
Mucolipidosis type II (MLII) is a rare lysosomal storage disorder caused by mutations in the GNPTAB gene located on chromosome 12q23.2. Our study was conducted to characterize the clinical and paraclinical features, as well as genetic variants, in pediatric patients diagnosed with MLII at the National Children’s Hospital. Our findings revealed that 100% of cases presented with classic manifestations, including severely short stature, coarse facial features, restricted joint mobility, and recurrent respiratory tract infections; cardiovascular complications and herniation were also documented in a subset of cases. Laboratory investigations demonstrated elevated serum lysosomal enzyme activities and elevated urinary glycosaminoglycan (GAGs) excretion in all children examined. This study underscores the value of combining characteristic clinical manifestations with genetic testing for the definitive diagnosis of MLII. The identification of novel variants contributes to the expansion of the genetic variant database and supports genetic counseling as well as prenatal diagnosis for at-risk families.
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Keywords
Mucolipidosis type II, I-cell disease, lysosomal storage disorder, GNPTAB, rare disease.
References
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