Studies were done to determine the cause for hypocalcemia, secondary hyperparathyroidism, osteomalacia and osteitis fibrosa cystica in a 22-year-old black woman. The patient had normal serum 25-hydroxyvitamin D (14 ng per milliliter) and markedly elevated serum 1,25-dihydroxyvitamin D (137 pg per milliliter). Vitamin D3, 4000 units per day for four weeks, increased the serum 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D to as high as 29 and 297 pg per milliliter, respectively, and corrected the hypocalcemia and secondary hyperparathyroidism. The results suggest that the disorder results from impaired end-organ response to 1,25-dihydroxyvitamin D. We propose that the entity be called vitamin-D-dependent rickets Type II.

No abstract

Thromboembolic events occur in about 27% of the patients with polycythemia vera and account for 31% of the deaths. These include cerebrovascular accidents, myocardial infarction, peripheral vascular occlusions, pulmonary infarctions, and venous thrombosis. We report two cases with polycythemia vera who presented with pulmonary hypertension in the absence of previous thromboembolic complications of any kind. One patient died suddenly, with evidence of extensive bilateral thrombosis of prelobular pulmonary arteries at autopsy. In the second patient, local thrombosis in the pulmonary vasculature or recurrent silent pulmonary emboli appear to be responsible for the development of pulmonary hypertension. After institution of anticoagulant therapy, he is able to maintain his functional status. The purpose of this report is to alert clinicians to the development of this insidious, but potentially fatal complication in patients with polycythemia vera.

Laryngeal atresia is a rare congenital anomaly requiring immediate tracheotomy as a lifesaving measure. A case of subglottic laryngeal atresia is reported and correlated with laryngeal embryogenesis. Three types of laryngeal atresia are described. Although tracheoesophageal fistula is commonly associated with laryngeal atresia, one must be careful not to confuse a pharyngotracheal duct with a tracheoesophageal fistula. A disproportionate number of reported TE fistulas associated with laryngeal atresia may result if an accurate distinction between pharyngotracheal duct and TE fistula is not made.