Endocrine Abstracts

Background: Fahr’s Syndrome, also known as striopallidodentate calcinosis is a rare form of neurological disorder characterized by abnormal calcified deposits in basal ganglia, cerebellar and cerebral cortex. Its prevalence goes from 2 to 12.5%. Etiology of this disorder is very wide and involves endocrinopathy, mitochondrial myopathies dermatological abnormalities, infectious disease or may be idiopathic. We present a case of a patient with diffuse brain calcifications due to pseudohypoparathyroidism probably type 1b.

Case description: We present a case of a 37 years old man who presented in the Emergency Unit with epileptic generalized tonic-clonic seizure. He was known to suffer from epilepsy since 4 months of age but head CT was performed for the first time during this hospitalisation and difuse bilateral brain calcifications were noticed. The patient has short stature with round face and brachydactyly of 4th metacarp. He also showed intellectual disability.Biochemical analysis showed hypocalcemia (6.1 mg/dl) with low/normal Vit D levels (29.8 ng/ml) and high PTH levels (152.1 ng/l). Hepatic and renal function were normal. Other electrolytes were also normal. Anterior hypophysis hormones were in their normal range. Because of hipocalcemia with high PTH levels and normal vit D, magnesium levels and renal function, diagnosis of pseudohypoparathyroidism was made. Lack of other hormone resistances, and clinical appearance suggests pseudohypoparathyroidism type 1b. The patient was treated with IV calcium and Vit D3 firstly and then with calcitriol 0.25/daily. On follow up levels of serum ionized calcium and 24 h calcinuria were improved.

Conclusions: Fahr’s Disease is a rare, neurological complication of chronic pseudohypoparathyroidism. In most cases the diagnose is clinical-radiological with diffuse brain calcifications. It is suggested that PTH plays a protective role against calcifications in the brain. The mechanism is not fully explained but it is emphasized the importance of PTH receptor 2, found in brain cells and mitochondrial superoxides. After confirming pseudohypoparathyroidism, the patients should start treatment with cholecalciferol or ergocalciferol (firstly to fill the depots) and calcium supplements. Because PTH is required for the renal conversion of calcidiol to calcitriol (active metabolite) calcitriol is often the treatment of choice.

Key words: calcium, PTH, hypoparathyroidism, pseudohypoparathyroidism, brain calcifications.