Basic and clinical evaluation of the measurement of bone resonant frequency

A new computerized apparatus was constructed to measure the resonant frequency of human ulna in vivo with high sensitivity and reproducibility. Experimental studies using aluminum bar and dried human bone revealed the importance of the ulna being positioned parallel to the radius, approximately 90 degree flexion of the elbow joint, and minimal muscle activity in order to demonstrate maximum resonant frequency of ulna. Measurement of bone resonance in monkeys in vivo and after removal of the bone in vitro showed good agreement. Product of F (maximum resonant frequency in Hz) and L (ulnar length in cm), FL, indicating the speed of propagation of sound wave through the ulna, showed a significant positive correlation with bone mineral content/bone width (BM/BW) measured by Norland-Cameron apparatus and age-bound decline in both sexes. Patients with osteomalacia and primary hyperparathyroid bone disease tended to have higher FL values than expected from BM/BW. Two-dimensional display of FL and BM/BW thus appears to be useful in distinguishing osteoporosis from osteomalacia better than the use of BM/BW alone.

Familial hypocalciuric hypercalcemia involving four members of a kindred including a girl with severe neonatal primary hyperparathyroidism

A family with hypercalcemia in four members is reported. The proband, a newborn girl presenting with inadequate sucking due to muscle hypotonia, marked thoracic deformity due to decalcification, hypercalcemia, and hypophosphatemia, suffers from cerebral damage due to hypoxia despite successful total parathyroidectomy of four hyperplastic glands and replacement therapy. Her 31-year-old father showed CCa/Ccr of 0.0094, normal serum Mg, hypercalcemia, hypophosphatemia and normal renal concentrating ability without kidney stone and bone abnormality. Subtotal parathyroidectomy caused only a transient fall of serum Ca. His half sister and her daughter also had symptomless hypercalcemia. Recognition of familial hypocalciuric hypercalcemia is important to avoid unnecessary parathyroid surgery and to respond effectively to severe neonatal primary hyperparathyroidism occasionally seen in such kindred.

Parathyroid hormone immunoreactivity in the plasma filtrate of uremic patients

Plasma filtrate of uremic patients concentrated and fractionated by gel filtration consisted of a large peak with C-terminal immunoreactivity and a small peak with N-terminal immunoreactivity. Further analysis of the first peak with C-terminal immunoreactivity by ion exchange chromatography revealed at least 3 peaks indicating the presence of three peaks with a similar immunological behavior but different charge. The elution profile in a patient under chronic hemofiltration was different in pattern compared with that in 2 patients under conventional hemodialysis.

A case of multiple endocrine neoplasia type II b: endocrinological evaluation and family screening

The case of a 27 year-old woman with typical manifestations of multiple endocrine neoplasia type II b is reported. Medullary carcinoma of the thyroid was detected on the occasion of an operation for goiter when she was 22 years of age. Constipation due to megacolon caused by intestinal neuroma had persisted since childhood. Neuroma of the tongue and lips, hypertrophic corneal nerve and Marfanoid habitus were also found. The presence of pheochromocytoma was suggested in view of the positive cold pressor and results of glucagon loading tests, but this remains inconclusive. There was prolonged and exaggerated response of growth hormone and luteinizing hormone after provocative tests for anterior pituitary gland, in spite of normal basal levels. Screening of her family members for medullary carcinoma of the thyroid was carried out by measurement of immunoreactive calcitonin. Two siblings were shown to be hypercalcitoninemic, presumably due to occult medullary carcinoma of the thyroid. This case appeared to be the first in Japan showing multiple endocrine neoplasia type II b accompanied by familial hypercalcitoninemia.