PTH and pseudohypoparathyroidism type 1B: She and her three brothers (33-year-old male twins, and a 21-year-old male) were diagnosed with pseudohypoparathyroidism type 1b (PHPT 1b) based on the presence of chronic HypoCa (serum Ca 1.6-1.85 mmol/l) since birth associated with significantly elevated plasma PTH levels in the range of 310-564 pg/dl (normal range 10-65) and absence of signs of Albright hereditary osteodystrophy.