ESPE Abstracts

Rendu-Osler-Weber syndrome (also called Hereditary Haemorrhagic Teleangiectasia) is an autosomal dominant disorder that results from multisystem vascular dysplasia. HHT syndrome has been described in association with autoimmune disorders, such as Hashimoto thyroiditis, lupus erythematosus, vitiligo, anti-phospholipidic syndrome and pernicious anaemia.

We present the case of a 6 year old girl with Rendu-Osler-Weber syndrome who was referred for endocrinological evaluation for moderate hypocalcemia discovered during a biochemical screening. The patient complained of paresthesia of the extremities without a history of carpal-pedal spasm, seizures or laryngospasm. Physical exam showed obesity (BMI 22.7 kg/m2, above 97^th percentile), no bone deformities, positive Chvosteck sign, dental dystrophia. During the initial endocrinological evaluation, blood tests showed low serum calcium (8.1 mg/dl and 7,1 mg/dl in two different ocasions), serum albumin (5.1 g/dl) and corrected calcemia (6.8 mg/dl), high phosphorus (7.4 ng/dl), low urine calcium (5 mg/500 ml, under the reserve of improper collection) and normal vitamin D levels (35.19 ng/ml). The parathyroid hormone concentration was inappropriately low (24.96 pg/ml). Cerebral CT scan showed no calcifications, hand X ray showed normal length of the metacarpal bones and no particular findings were found on electrocardiogram. Based on the clinical and biochemical evaluation the diagnosis of hypoparathyroidism was established. She was given alphacalcidolum in doses of 0.25 ug and 500 UI colecalciferol, and put on a low phosphorus diet. She was advised to have an adequate intake of calcium. Under treatment, at one month evaluation the calcium corrected (serum calcium 8.4 mg/dl).

We present this case because of the rare association between HHT and hypoparathyroidism. To our knowledge, there is only one clinical case report of two brothers with clinical manifestations of HHT in addition to severe hypocalcemia associated to hypoparathyroidism. One possible explanation for this rare association can be the autoimmune etiology of hypoparathyroidism since other autoimmune disorders were reported to be found in HHT. However, the mechanism underlying the connection between HHT and autoimmune disorders is not yet clarified. Nowadays, there are no sufficient data to justify the coexistence of these two rare diseases.