Endocrine Abstracts

Pseudohypoparathyroidism (PHP) is group of heterogeneous disorders characterized by hypocalcemia, hyperphosphatemia and elevated paratormone (PTH) levels as a result of end-organ resistance to PTH. Basal ganglia calcification (BGC) in states of hypoparathyroidism is not uncommon. In PHP, BGC can occur up to 50%; the pathogenesis is poorly defined. The aim of our study was to evaluate the prevalence of BGC at baseline observation in a series of patients with PHP followed at a tertiary center. The diagnosis of PHP was based on clinical features and confirmed by genetic analysis. We evaluated 21 patients with a mean age of 21±12 (7 males and 14 females) with a diagnosis of PHP type I (1A, n=5; 1b, n=13), pseudopseudohypoparathyroidism (n=1). Two patients were negative at genetic screening. Five (23.8%) subjects had familial PHP type 1A. All patients underwent brain computed tomography (CT, n=20) or magnetic resonance imaging (MRI, n=1) to detect the presence of BCG. Biochemical and clinical data were available for all patients. BGC were present in 8 (38,1%) patients (7 in PHP type 1b and one in type 1A). 37% were present in males and 62% percent in females, (P=0.5). The localization of BCG was pallidum in two patients, all basal ganglia in two, pallidum, cerebellum and caudatum in one, cortical-subcortical junction and caudatum in one, pallidum, striatum and cortical-subcortical junction in one and pallidum and subcortical area in one. Four (19%) patients had other cerebral calcifications, localized in cerebral falx (n=1), in pineal gland (n=1), choroid plexus (n=1) and soft cerebral tissue (n=1). Before diagnosis, two of 21 (9.5%) patients presented seizures and one (4.8%) neurocognitive alterations; none of them had BCG. Three patients had soft tissue calcification and two of them also had BCG. Eight patients (38%) presented signs or symptoms of hypocalcemia before the diagnosis, and all but one had BCG. At baseline evaluation, 6 of 21 patients were taking calcium supplements and calcitriol. Mean serum calcium, phosphate and PTH levels were 7.7±1.5 mg/dl, 4.863±1.8 and 440.1±397 pg/ml, respectively. In conclusion, our study finds a high rate of BCG in patients with PHP, with no significant difference between gender. Calcifications were detected in different cerebral sites, usually without clinical manifestations. However, their clinical value is still unclear. Our results suggest evaluating the presence of BCG in PHP and monitoring them with CT o MRI during follow-up.