Case#: 22-month-old Norwegian female patient

DiseaseAssertion: MPS-H

FamilyInfo: Mother and father received parental testing.

CasePresentingHPOs: Joint stiffness (HP:0001387)

CaseHPOFreeText: She had a tendency to fall without normal protective reactions. Typical facial appearance and other clinical findings were suggestive of MPS I Hurler, and this diagnosis was also supported by X-ray images which showed characteristic skeletal changes. Motor development appeared slightly delayed, while intellectual development was considered to be normal.

CaseNotHPOs: Corneal clouding (HP:0007957)

CaseNotHPOFreeText: N/A

CaseEnzymeAssay: 0.006 μmol phenol/18 h/mg protein. Normal range of IDUA activity (n = 52, healthy volunteers): 0.143–0.351 μmol phenol/18 h/mg protein.

CaseUrineGAGs: Urinary GAG excretion - 101 mg GAG/mmol creatinine. The patient demonstrated increased excretion of GAGs, which were identified as HS and DS. Normal age adjusted range of urinary GAG excretion: 14–34 mg GAG/mmol creatinine.

CaseERT: The patient was initiated on enzyme replacement therapy (ERT) with weekly infusions of recombinant α-l-iduronidase 100 IE/kg

CaseBMT: The patient successfully received hematopoietic stem cell transplantation (HSCT) 4 months after ERT.

Variant1: c.1727+3G>C

Variant1ClinVarID: 4817926

Variant1CAID: CA91171181

Variant2: c.208C>T (p.Q70X)

Variant2ClinVarID: 11909

Variant2CAID: CA204563

AdditionalVariants: N/A

ParentalGenotype: Mother: c.208C>T (p.Q70X); 0.071 μmol phenol/18 h/mg protein (IDUA activity). Father: c.1727+3G>C; 0.079 μmol phenol/18 h/mg protein (IDUA activity).

PreviouslyPublished N/A