Open AccessFamilial Hypocalciuric Hypercalcaemia (FHH): A Case Report
Author(s) -
Tivya Kulasegaran,
Pranav Kumar
Publication year - 2018
Publication title -
international journal of innovative research in medical science
Language(s) - English
Resource type - Journals
ISSN - 2455-8737
DOI - 10.23958/ijirms/vol03-i09/433
Subject(s) - hypocalciuria , hypercalcaemia , asymptomatic , calcium sensing receptor , medicine , primary hyperparathyroidism , endocrinology , parathyroid hormone , gnas complex locus , hyperparathyroidism , hypoparathyroidism , differential diagnosis , gastroenterology , calcium , chemistry , gene , biology , pathology , genetics , hypomagnesemia , organic chemistry , magnesium
Familial hypocalciuric hypercalcaemia (FHH) is a rare genetic autosomal dominant disorder, with 3 variants described. An inactivating mutation in the calcium sensor receptor (CASR) gene causes the subtype 1, which represents 65% of the cases. Inactivation of Ca-sensing receptors (CaSR) can also lead to hypercalcemia associated with increased parathyroid hormone (PTH) secretion.[1]
It is characterised by causes mild asymptomatic hypercalcemia[2] and hypocalciuria with normal or elevated PTH. FHH is generally asymptomatic and treatment is not needed. Differential diagnosis with primary hyperparathyroidism (PHPT) is crucial and based on calcium-creatinine clearance ratio (CCCR), which, when under 0.02 points to the diagnosis of FHH.[3] Genetic test is necessary for confirmation.[4]