ESPE Abstracts

Background: Pseudohypoparahthyroidism is a rare genetic disorder that is characterized by unresponsiveness to parathyroid hormone and abnormal calcium regulation. Several subtypes have been established according to clinical appearance, resistance of other hormones, and recent genetic findings. Although little is known about the pathogenesis of heterotopic calcifications of soft tissues and brain, they are frequently found.

Objective and hypotheses: Evaluation of cerebral calcification during 15-year period in a patient with pseudohypoparathyroidism.

Method: We present a male patient with pseudohypoparathyroidism and basal ganglia calcification. This is the first child in a family with unaffected parents. Hypocalcemic convulsions occurred in the neonatal period, considered as transient and no further investigations were made. At the predpubertal age hypocalcemic convulsions occurred. Examination didn’t reveal dysmorphism or skeletal anomalies. Biochemical evaluation established the diagnosis of pseudohypoparathyroidism – severe hypocalcemia (1.7 mmol/l), hyperphosphatemia (2.9 mmol/l), and high levels of PTH (1050 pg/ml). No other hormone resistances except to PTH were found. CT scan has been done several times from establishing the diagnosis.

Results: CT of the brain that has been made at the beginning before treatment showed slightly dispersed calcification spread radially between gray and white matter. In the following years, after initiation and prompt titration of the therapy with calcium carbonate and calcitriol, several other scans have been made, all showing fluctuation in calcifications towards basal ganglia. The extent of calcification broadened in the first years, followed by reduction after the stabilization of PTH level.

Conclusion: Although calcification of basal ganglia is a well-established feature in pseudohypoparathyroidism, there are very few studies in the literature showing the changes in the amount of the calcified regions during the treatment. Monitoring of calcification is an important tool in titrating the therapy in patients.