Dihydrotachysterol and Vitamin D Resistance in Renal Failure

Vitamin D and dihydrotachysterol have been used for the treatment of hypoparathyroidism and osteomalacia for many years. Recently, experimental and clinical evidence has suggested that these compounds under certain circumstances may have quite different potencies when expressed on a weight basis.^1,2 This report illustrates this phenomenon.

Patient Summary  A 56-year-old English-born nurse was first found to have hypertension at the age of 33 years. Investigation revealed a blood pressure of 180/110 mm Hg and normal results of urinalysis. The blood urea level was 26 mg/100 ml (normal, 20 to 40 mg/100 ml). Subsequent symptoms included constipation and one episode of colicky abdominal pain with dysuria. A lumbar sympathectomy was carried out for her hypertension when she was 36 years of age. At the age of 50 years the patient was found to be hypercalcemic and to have mild renal failure and was placed on reserpine therapy. Her laboratory findings