A Case of Low Bone Mineral Density with Vitamin D Deficiency Due to Prolonged Lactation and Severe Malnutrition

Malnutrition associated vitamin D deficiency contributes to the calcium loss from bone and results in osteoporosis and osteomalacia at final stage. Osteomalacia is characterized with softening of bone secondary to defective bone mineralization. Here, we report a case of possible osteomalacia caused by prolonged lactation and severe malnutrition in 35-year-old female. She was a housewife and her body mass index was 11.8 kg/m(2). She was diagnosed with severe osteoporosis in regular health check-up 2 years ago, but did not take any medication. Nine months ago, she had been treated with anti-tuberculosis medications for 6 month due to active pulmonary tuberculosis. After complete remission of pulmonary tuberculosis, she had lost her appetite severely. Furthermore, she felt gait difficulty and suffered from generalized bone pain. On serologic examination, hypocalcemia, hypophosphatemia, high alkaline phosphatase, low vitamin D3 and high parathyroid hormone level were seen. In the bone mineral density, Z-score from her lumbar spine was -6.5. She was treated with oral calcium and vitamin D3 intramuscularly. After 1 year treatment, she felt significant improvement in bone pain and could walk alone. Also her serum calcium, phosphate and vitamin D3 level are all normalized.