Long-Term Cardiorespiratory, Endocrine, Ophthalmic, and Functional Outcomes in Adult Patients with Mucopolysaccharidosis Type I (Hurler Syndrome) Post Haematopoietic Stem Cell Transplantation: The Irish Experience

Abstract Mucopolysaccharidosis type IH (MPS IH) is caused by homozygous IDUA gene pathogenic variants. This results in deficiency of the enzyme α-L-iduronidase (IDUA), which is necessary for the degradation of glycosaminoglycans (GAGs). This study outlines the long-term outcomes in adult Irish patients affected with MPS IH, who were followed up for mean 28 years post Haematopoietic Stem Cell Transplantation. Nineteen adult MPS IH patients underwent HSCT in childhood. The participant cohort represents 6 families. Among the 13 patients with Irish Traveller ethnicity, 6 patients were either siblings or first cousins. All these related patients were homozygous for p. Trp402Ter (W402X). Mean age at the first transplantation was 8 months (range 3-21). Five patients had undergone a second transplantation (n=5, 26%) in childhood, due to graft failure. None of the patients had a cardiac valve surgery at the time of the study. 14/19 patients had mild to moderate aortic or mitral valve insufficiency or stenosis. 3/19 patients used non-invasive ventilation at night. Two patients had tracheostomy in situ. Both sensorineural as well as conductive hearing defects. No corneal clouding post corneal transplantation (n=8) was observed. Six patients attended regular secondary school. Multidisciplinary follow-up is needed to address the disease specific complications in adulthood.

Serial Spectral Domain Ocular Coherence Tomography Measurement of Outer Nuclear Layer Thickness in Rhegmatogenous Retinal Detachment Repair.

INTRODUCTION: The outer nuclear layer (ONL) contains mostly photoreceptor bodies and reduced post-operative ONL thickness (ONLT) is associated with poor visual outcome in rhegmatogenous retinal detachment (RRD). METHODS: Spectral domain ocular coherence tomography was recorded before and 6 weeks following RRD repair in 27 consecutive patients. RESULTS: The repair consisted of combined 20-guage pars plana vitrectomy (PPV) and encirclement in 66.7% of cases, 22.2% underwent PPV alone and 11.1% scleral buckle alone. The mean (± standard deviation) ONLT was reduced in detached retinae (94.1 ± 31.1 microns) compared to the unaffected eye (119.5 ± 26.8 microns). Postoperatively the ONLT increased to 103.3 (± 32.8) microns. ONLT at presentation in the affected eye is significantly and positively correlated with the final ONLT in the affected eye (Pearson's correlation: r = 0.80, p = 0.029). CONCLUSION: The finding that ONLT is reduced in detached retinae carries implications for visual prognosis.