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IEMbase 0244: NAGLU-related N-acetylglucosaminidase deficiency

Scope

Field Value
IEMbase ID 244
Nosology 20.2.04.01
Gene NAGLU
External IDs OMIM:252920
Generated mapping MAPPED; Sanfilippo_syndrome.yaml#MPS IIIB
Candidate DisMech targets Sanfilippo_syndrome.yaml#MPS IIIB
Review date 2026-07-07

IEMbase phenotype signal

IEMbase represents this as NAGLU-related N-acetylglucosaminidase deficiency, with alternate labels Sanfilippo B disease, mucopolysaccharidosis type 3B, and MPS IIIB. The record is autosomal recessive and treatability is marked yes, with no treatment rows in the cached JSON.

Biochemical rows include decreased alpha-N-acetyl glucosaminidase activity and increased urinary heparan sulfate and total glycosaminoglycans. Clinical rows include Alder-Reilly anomaly, diarrhea, dysostosis multiplex, hearing loss, liver dysfunction, retinopathy, and sleep disturbances. Characteristic rows include aggressive behavior, coarse facial features, hyperactivity, intellectual disability, neurologic regression, seizures, and swallowing difficulties.

DisMech phenotype coverage

Sanfilippo_syndrome.yaml#MPS IIIB is the correct local target. The local file has subtype coverage for NAGLU-related Sanfilippo syndrome type B/alpha- N-acetylglucosaminidase deficiency. The shared Sanfilippo entry covers autosomal recessive inheritance, failed heparan sulfate catabolism, heparan sulfate storage, neuroinflammation, progressive neurodegeneration, developmental regression, intellectual disability, behavioral disturbance, hyperactivity, sleep disturbance, seizures, swallowing and feeding difficulty, hearing and visual impairment, mild skeletal/systemic involvement, and supportive plus investigational treatment context.

Concordance and completeness

Judgement: correct subtype-level mapping with high concordance.

IEMbase and DisMech agree on NAGLU/MPS IIIB identity, the deficient lysosomal enzyme, heparan sulfate storage, total GAG elevation, progressive neurologic and behavioral disease, seizures, sleep disturbance, and swallowing difficulty. IEMbase adds concise per-subtype prompts for Alder-Reilly anomaly, diarrhea, dysostosis multiplex, liver dysfunction, and retinopathy.

Curation actions

  • Keep this record mapped to Sanfilippo_syndrome.yaml#MPS IIIB.
  • No mapping correction is needed.
  • Use IEMbase's subtype-specific enzyme and clinical checklist rows as enrichment prompts for future Sanfilippo review.