Calcification of Soft Tissues in a Family, Case Report and Review of Pseudohypoparathyroidism

Abstract

Pseudohypoparathyroidism and pseudo-pseudohypoparathyroidism are rare genetic disorders of calcium metabolism and resistance to the action of Parathormone. Although the genetic details of these conditions are not fully diagnosed, role of gene coding for stimulatory G protein locus was studied and imprinting in its inheritance was proved. We report three cases of a family member with calcification in soft tissues that show Pseudohypoparathyroidism in father and his sister and pseudo-pseudohypoparathyroidism in his son. history of two times seizure in the past years. The patient's paternal aunt had similar objective finding similar to patient's father but she didn't agree to involve in our assessment. The parents was non-consanguineous and the mother had not the same problems and was normal in physical examination and anthropometric evaluation. The other 3.5 year old boy of this parent had not objective specific finding. In evaluation of 33 year old father, low total calcium level (6.9 mg/dL), high phosphorus (5.5 mg/dL), normal Alkaline phosphatase (277 U/L), very high PTH (650 pg/ml), normal kidney and thyroid function tests were found. The 25-OH-Vit D was in mid-normal range and ultrasound evaluation of kidneys do not demonstrate significant pathology. The brain CT scan showed calcification of basal ganglia and cerebellum nuclei (Figure 2). KeywordsAccording to clinical and para-clinical findings, such as hypocalcemia, hyperphosphatemia, elevated PTH, shortening of metacarpus, facial sign and subcutaneous calcification, the father's disease is a classic form of PHP type I (a or c) with AHO features but without obvious other evaluated hormone resistance. Differential diagnosis for subcutaneous ossification in our target child were: dystrophic soft tissue calcification, causing chondro-calcinosis, Fibrodysplasia ossificans progressive, posttraumatic osteoma cutis, metastatic calcification, idiopathic tumoural calcinosis, scleroderma, dermatomyositis, cysticercosis, myositis ossificans and soft tissue sarcoma. These wide range of differential diagnosis from trauma to malignancy were simply narrowed when his father's observed after a simple family history taking! Multiple subcutaneous calcifications in a child when his father shows a classic form of PHP, strike PPHP in the mind because of its genetic nature. As we discuss it in the next section, in a family with history of PHP when the father is the origin of gene, its imprinting led to PPHP in child. When a child has PPHP, and the father shows PHP features, the father's type of PHP is Ia. In the absence of genetic study and evaluation of urine cAMP after synthetic PTH administration it is difficult to say our diagnosis is definite. According to European PHP network classification for PHP the father case has two major criteria and is a case of "inactivating PTH/PTHrP signaling disorder" (iPPSD) without genetic study. PathophysiologyBecause of critical function of calcium ion in much vital enzymatic process and electrical activity of neuron, muscle conducti...