Increased pituitary volumes in patients with Sanfilippo syndrome (mucopolysaccharidosis type 3, MPS III)

Purpose: To evaluate apparent pituitary gland enlargement inpatients with Sanfilippo syndrome observed at our institution. Methods: Twelvepatients with Sanfilippo syndrome with brain MRI were studied. Anterior,posterior, and whole pituitary volumes were estimated using the prolateellipsoid volume calculation method (π/6 × L × W × H). Convexity along the upperpituitary margin (Elster’s grade) was also measured. These values were comparedto two age- and sex-matched groups (normal controls and patients with Hurlersyndrome) using one-way ANOVA followed by Tukey’s post hoc analysis for multiplecomparisons. Results: In theSanfilippo cohort, the mean whole pituitary volume was 529.9 mm, the meananterior pituitary volume was 333.4 mm, and the mean posterior pituitary volumewas 59.1 mm with Elster’s grade of 4.2. In the control cohort, the mean wholepituitary volume was 217.4 mm, the mean anterior pituitary volume was 154.8 mm,and the mean posterior pituitary volume was 28.4 mm with Elster’s grade of 2.5.In the Hurler syndrome cohort, the mean whole pituitary volume was 310.0 mm,the mean anterior pituitary volume was 178.2 mm, and the mean posteriorpituitary volume was 35.4 mm with Elster’s grade of 3.5. Conclusion: In ourcohort of patients with Sanfilippo syndrome, whole, anterior, and posteriorpituitary volumes and degree of convexity along the upper pituitary border wereall significantly greater than controls. The cause of these morphologicalchanges is unclear, as is clinical correlation of the findings.