P82 – 2690: Surgical history in the child neurology clinic and consideration of Hunter syndrome: Insights from the Hunter Outcome Survey (HOS)

Abstract

Objective Hunter syndrome (mucopolysaccharidosis type II, MPS II, OMIM 309900) is a lysosomal storage disease with progressive multisystem manifestations caused by a deficiency in the enzyme iduronate-2-sulfatase. Prompt diagnosis and treatment may improve patient outcomes, but delays in diagnosis are common. This analysis used data from Hunter Outcome Survey (HOS) to assess the potential role of paediatric neurologists in achieving earlier diagnosis of Hunter syndrome. Methods HOS is a global, multicentre, longitudinal registry that collects comprehensive real-world data on the natural history of Hunter syndrome and the long-term safety and effectiveness of enzyme replacement therapy with idursulfase (Elaprase®). The registry contains data from patients followed prospectively, as well as from those who were deceased at HOS entry. We analysed data on neurological signs and symptoms and surgical procedures that preceded formal diagnosis in prospective patients in HOS. Results As of 15 September 2014, 864 patients were followed prospectively in HOS; median ages at symptom onset and diagnosis were 1.5 and 3.2 years, respectively. Of 587 patients with available information, 51 (8.7%) were first suspected of having Hunter syndrome by neurologists/neurosurgeons. Information on neurological manifestations was available for 797 patients; 184 (23.1%) had neurological symptoms before diagnosis, with cognitive impairment (13.3%), behavioural problems (both 13.0%), and gait abnormalities (5.6%) being most common. Of 666 patients who required surgery at any time, 52.0% had first undergone surgery before diagnosis, with hernia repair (46.3%), tympanostomy (36.3%) and adenoidectomy (38.8%) being most common. Conclusion Consulting neurologists may play an important role in identifying patients with Hunter syndrome and initiating appropriate follow-up. Multiple ear, nose and throat procedures or hernia surgeries are a diagnostic clue for consideration of Hunter syndrome, especially in patients with other characteristic disease symptoms, such as dysmorphic facial features, dysphagia, airway problems, seizures, joint stiffness, developmental delay or carpal tunnel syndrome.