In the adult patient with iduronidase deficiency, the dysmorphic features are often very mild and there are different priorities with regard to management. The clinical picture is dominated by the orthopedic complications. Poor hand function is due to chronic carpal tunnel syndrome. Progressive joint stiffness and severe back pain are usual. As the patient grows older corneal clouding may interfere with vision and corneal grafting might be needed.
Death usually occurs in the first decade as a result of cardiorespiratory failure.
In a recent review, a series of 46 patients with this type were studied. Severely affected patients share many of the features of classic Hurler s syndrome, but tend to be milder and have less skeletal involvement. The classic nodular rash said to be pathognomic of this disorder is rare and has been observed in only two patients. Again, ear, nose, throat and airway problems dominate the clinical course. In addition patients are prone to severe bouts of diarrhea, the cause of which remains obscure.