Table 1.
Checklist of MPS I signs and symptoms. When one of these signs is present, check for other signs. MPS I should be suspected when at least two of the signs occur together
| Suspicious findings | Details |
|---|---|
| Airway obstruction | Obstructive sleep apnoea, snoring, macroglossia, gingival hypertrophy, difficulty with intubation |
| Cardiac valvular disease/cardiomyopathy | Heart insufficiency/failure |
| Carpal tunnel syndrome | Mainly in children or young adults: bilateral and recurrent |
| Coarse facial features | Progressive (from mild to severe): large head, bulging forehead, thick lips, widely spaced teeth, large tongue and short, flat nose with wide nostrils. Not often typical in Hurler–Scheie and Scheie |
|
Corneal clouding Developmental delay |
Progressive visual impairment Initial symptom‐free interval, then delayed acquisitions followed by a plateau and loss of previously acquired skills (only in the severe phenotype) |
| Dysostosis multiplex | Hip dysplasia, scoliosis, kyphosis, gibbus, genu valgum, odontoid hypoplasia |
| Family history | Sibling affected with MPS I |
| Growth retardation | Deviation from the growth curve, short stature |
| Hepatosplenomegaly | Enlargement of both the liver and spleen |
| Hydrocephalus | Mainly in severely affected patients |
| Inguinal and umbilical hernia | Mainly when bilateral (inguinal) or recurrent |
| Joint contractures or stiffness without inflammation | Thickening of joint capsules, contractures/stiffness of joints, progressive difficulties in performing daily activities, including walking |
| Psychiatric symptoms | In adults with attenuated phenotype |
| Repeated ear, nose and throat infections/upper respiratory tract infections in the first years of life | Recurrent rhinitis or otitis media in the first years of life – also occurring before social mixing and not necessarily related to concomitant infections in other siblings – hearing loss, early adenotonsillectomy, t‐tubes |
| Spinal cord compression | Mainly cervical and thoracic |
| Trigger fingers | Progressive, hands and toes, short, broad hands with curving fingers |
MPS I, mucopolysaccharidosis type I.