Endocrine Abstracts

Introduction: Pseudohypoparathyroidism (PHP) is a state of parathyroid hormone resistance and is characterised by low serum calciumand elevated serum phosphate and parathyroid hormone level

Case descriptions: We describe three cases diagnosed with PHP. Case 1: 14 year old male, known case of hypothyroidism, presented with carpopedal spasm and on treatment with 75 mg oflevothyroxine, with short height of 143 cm (less than 3rd percentile), BMI 23.23 kg/m² which was deemed to be overweight as per Indian Academy of Pediatrics (IAP) standard. The patient had signs of Albright Hereditary Osteodystrophy (AHO). Investigations revealed hypocalcemia (serum calcium 6.2 mg/dl), hyperphosphatemia (serum phosphorus level of 6.5 mg/dl) and high levels of Parathyroid Hormone (PTH) (889 pg/ml), normal vitamin D levels (25 OHD–63.2 ng/ml). Alkaline Phosphatase (AP) levels were normal. TSH, FSH and calcitonin levels were elevated, with Sexual Maturity Rating (SMR) Tanner III and low testicular volume of 5 ml. Case 2: 13 years female presented with carpopedal spasm with signs of AHO, with short height of 128 cm (less than 3rd percentile), BMI 22.89 kg/m² (overweight). Investigations revealed hypocalcemia (serum calcium 5.8 mg/dl), hyperphosphatemia (serum phosphorus level of 4.8 mg/dl) and high levels of PTH (221 pg/ml), normal vitamin D levels (25 OHD −70.1 ng/ml), with elevated AP levels. TSH levels were normal. Patient had primary amenorrhea, hence had not attained menarche. FSH levels were 2.1 mIU/ml, LH 0.97 IU/l E 22 pg/ml. Case 3: 11 year old male presented with carpopedal spasm and convulsions. Investigations revealed hypocalcemia (serum calcium 7.3 mg/dl), hyperphosphatemia (serum phosphorus level of 7.56 mg/dl) and very high levels of PTH (1879 pg/ml), with normal AP. No signs of AHO, normal height, SMR was prepubertal with normal TSH levels.

Discussion: We diagnosed these as PHP based on the current global consensus statement with PTH resistance for the association of hypocalcaemia, hyperphosphataemia and elevated PTH in absence of vitamin D deficiency with normal magnesium levels and renal function. The case 1 with possible G(s) protein resistance, as FSH, TSH and calcitonin were high was diagnosed as PHP 1a. The second case was categorized PHP 1b but PHP 1a cannot be ruled out. Further, molecular analysis would have assisted with a precise diagnosis. The third case was diagnosed as PHP type 2. The management plan was based on true hypoparathyroidism including Vitamin D supplementation, with varied prognosis