Longitudinal clinical and imaging analysis of hydrocephalus in a single-center study in 57 patients with mucopolysaccharidosis type IH (Hurler syndrome).

Objective: Hurler syndrome (mucopolysaccharidosis type IH [MPS IH]) is the most severe form of MPS type I. Hydrocephalus can be an early manifestation, but currently there are no established guidelines to monitor for its development or progression in these patients, either before or after treatment.

Methods: In this retrospective study, the records of 57 patients with MPS IH who received a hematopoietic stem cell transplant at the University of Minnesota were reviewed, and 291 brain MRI studies were analyzed. Ventricular size over the years was measured using the fronto-occipital horn width ratio.

Results: Fifty-seven patients were included in the analysis. Fifty-one patients without a shunt showed a decrease in ventricular size and eventual stability of ventricular size about 2 years after transplant. No new cases of hydrocephalus as part of the natural disease process requiring shunt placement were observed after transplant (0%, 95% CI 0%-5.8%).

Conclusions: In patients without preexisting hydrocephalus, no new cases of hydrocephalus developed, and ventricular size stabilized within 2 years after transplant. The authors call into question the overall utility of serial brain MRI after transplant in patients with MPS IH.