Aim: Mucopolysaccharidoses (MPS) are a heterogeneous group of diseases characterised by systemic manifestations due to impaired glucosaminoglycans (GAG) degradation within lysosomes. Mucopolysaccharidosis type II (MPS II, Hunter) is a lysosomal disease caused by mutations in the iduronate-sulfatase (IDS) gene. MPS II is inherited in an X-linked recessive manner. Mucopolysaccharidosis type III (MPS III, Sanfilippo) is an autosomal recessive lysosomal disease. It has four subtypes (A, B, C, and D). MPS II and III particularly exhibit significant central nervous system involvement. Early clinical manifestations may include cognitive delay, behavioural disturbances, progressive behaviour-sleep problems, delayed speech, autism-like features, and unexplained intellectual disability. Materials and Methods: In this retrospective study, we recorded the clinical findings of patients who were diagnosed with mucopolysaccharidosis type II and III and presented with neuropsychiatric symptoms such as seizures, developmental delay, speech impairment, and loss of neurological milestones. Results: The study included eleven cases, comprising 6 (54.5%) males and 5 (45.5%) females. Among them, 4 (50%) were diagnosed with MPS IIIA, 3 (37.5%) with MPS IIIB, and 1 (12.5%) with MPS IIIC. Six patients (54.5%) had speech delay, while two (18.1%) had cognitive delay, and three (27.2%) had hyperactivity, with nine (81.8%) experiencing motor delay. The mean age at presentation was 8.4 (±5.2 SD) years, with six patients (54.5%) receiving physical therapy and special training. Conclusion: In patients presenting with neuropsychiatric symptoms, consideration of mucopolysaccharidoses along with urine GAG, enzymatic assays and, when indicated, genetic testing is crucial for early diagnosis and intervention.
Erdem et al. (Mon,) studied this question.