Brownstein et al. (2008) described a 23-year-old woman with hypophosphatemic rickets and hyperparathyroidism who presented at 13 months of age with a prominent forehead, large open anterior fontanel, knobby wrists, moderately bowed legs with refusal to stand, and ... Brownstein et al. (2008) described a 23-year-old woman with hypophosphatemic rickets and hyperparathyroidism who presented at 13 months of age with a prominent forehead, large open anterior fontanel, knobby wrists, moderately bowed legs with refusal to stand, and 'rachitic rosary' of the anterior ribs. Radiographs of knees and wrists showed florid rachitic changes of the growth plates. After unsuccessful treatment with vitamin D2 for presumed nutritional rickets, further evaluation revealed hypophosphatemia and elevated serum parathyroid hormone (PTH) levels with inappropriate renal phosphate wasting, and treatment was changed to 1,25(OH)2-vitamin D with oral phosphate salt supplementation; her bone pain improved, and she began to walk shortly before her second birthday. At age 7 she developed hypercalcemia and upon examination was noted to have normal leg alignment with no bowing, macrocephaly, prominent frontal bossing, and dysplasia of the nasal bones with exaggerated midface protrusion. She had persistent hypophosphatemia with hypercalcemia and hyperparathyroidism, and underwent surgical removal of 3.5 hyperplastic parathyroid glands; histology showed benign multigland hyperplasia. At age 19 years she redeveloped hypercalcemia, and underwent 75% removal of the then-enlarged parathyroid remnant, with histopathology again showing benign hyperplasia. At age 23, she had intermittent headaches and was found to have Arnold-Chiari I malformation; she had an adult height of 151 cm with normal leg alignment, a mildly elevated PTH, and was functioning well at university studies.