Idiopathic Juvenile Osteoporosis

Abstract

IDIOPATHIC juvenile osteoporosis is a rare, selflimiting condition, unassociated with the classic causes (5) of osteoporosis. Its onset is noticed between the ages of eight and twelve years. Roentgenographically it often appears as a widespread demineralization, vertebral collapse, or fracture of long bones. These findings elucidate the initial clinical symptoms, which are usually focal or generalized pain. Spontaneous clinical and roentgenographic improvement is eventually seen in most of these patients, so no specific therapy is indicated. Case Report Severe pain of 2-months duration in the left hip of this 15-year-old girl prevented weight-bearing and was not preceded by injury. Similar pains in both knees and ankles two years previously had improved spontaneously. The girl had lost 2-3 inches in height over the preceding eighteen months. Intake of calcium was adequate. No medications had been administered; specifically, no cortisone. Otherwise, the health had been normal. There was no family history of bone disease. The patient was moderately obese, and secondary sex characteristics were present. Height was 5 feet 6 1/2 inches (168.91 em), weight 160 pounds (72.6 kg), and blood pressure 124 systolic and 84 diastolic. Pain in the left hip limited flexion and internal rotation. No muscular atrophy or arthritis was evident in any joint nor were striae, hirsutism, bruising, or other stigmata of Cushing's syndrome seen. Distribution of axillary and pubic hair was normal. The thyroid was not palpable and there was no clinical evidence of thyrotoxicosis. Except for the osseous lesions depicted (Figs. 1–4), the results of all roentgenographic studies, including intravenous urography, upper gastrointestinal barium examination, and barium enema study, were within the limits of normal. Laboratory determinations of the following were normal: hemoglobin, leukocyte count (total and differential), erythrocyte sedimentation rate, serial electrolytes, serum protein electrophoresis, cholesterol, alkaline phosphatase, blood urea, creatinine and creatinine clearance, serum carotene, quantitative analysis of stool for fat, triolein fat absorption, D-xylose absorption, protein-bound iodine, urinary 17-ketosteroids and 17-hydroxycorticosteroids, blood cortisol levels, tubular absorption of phosphate, and glucose tolerance. Radioactive iodine uptake was 20 per cent and the thyroid scan was normal. A liver scan with technetium 99 was normal. Serial determinations of serum calcium were 9.7, 10.5, 10.3, 10.6, and 10.1 mg/100 ml. Those of serum phosphorus were 3.5, 4.3, 4.5, and 4.3 mg/100 ml. The twenty-four-hour urine specimens examined for amino acids and hydroxyproline were normal. Antinuclear antibody determination was negative and the white blood cells showed normal activity of leukocytic alkaline phosphatase.