A Case of Nutritional Osteomalacia in Young Adult Male
Patient: 30-year-old, male\nChief complaint: walking disturbance, hip-joint pains, cramps in both pelvic limbs\nCurrent medical history: The patient is vegetarian without any unusual medical history. He owns a private business; he usually transfers light objects within 10 kg. Since about 1-2 years ago, he had pain on his legs when walking and difficulties to run and walk up stairs. Also, he sometimes had cramps at hip-joint and hip muscles but he didn't experience much inconvenience in daily life. Three months before visiting a hospital, he did intensive work to carry things while moving so he had more serious pains at hip-joint part. Then the patient experienced difficulties in walking and abnormalities and oppressive pains around coccyx. He was disturbed while in sleep since he couldn't lie down due to the severe pains and cramps occurred as he spread his legs more. A half month before the hospital visit, he couldn't sleep due to serious cramps without specific reasons and then he came into neurology department out-patient clinic of the hospital in order to have additional examination and treatments.\nPast history: The patient had no special past history such as hypertension, diabetes, hepatitis, and tuberculosis etc.\nFamily history: No one in his family had special past history including hypertension, diabetes, hepatitis, and tuberculosis etc. All family members (parents and five brothers and sisters) except for the patient are normal dieters who eat meats and had normal height and body weight.\nSocial history: The patient is a non-drinker and non-smoker. He is single and works at home as he owns his private business. He was reluctant to go out since his walking had changed. He didn't go out for about a year and he went out at night if necessary.\nSystemic review and physical examination findings: In bio-vitality index from body examination, systolic blood pressure, diastolic blood pressure, pulse, breathing, and temperature were 118 mmHg, 58 mmHg, 84 times per minute, 20 times per minute, and 36.8℃, respectively. Height and body weight were 168.0 cm and 50.9 kg, respectively, the body weight had not been changed for several years. Deformation on upper pelvic limb or body was not observed. The patient claimed pains in both hip joints when walking or carrying heavy stuff. As he had pain like pulling behind of both legs when walking fast, he couldn't run and exhibited waddling gait. In neurologic examination, left and right were symmetric and strength index showed 4+, indicating slight muscle weakness.\nExamination findings: In peripheral blood examination, leukocyte, hemoglobin, and thrombocyte were 8,100/mm3, 13.8 g/dL, and 268,000/mm3, respectively. In serum biochemical examination, total protein (7.9 g/dL), albumin (4.3 g/dL), blood urea nitrogen (15.9 mg/dL), creatinine (0.7 mg/dL), sodium (138 mmol/L), potassium (4.1 mmol/L), chlorine (102 mmol/L), and carbon dioxide (24 mmol/L) exhibited normal. Phosphorus (2.4 mg/dL; reference value 2.7-4.5), calcium (6.0 mg/dL; reference value 8.2-10.2), and ionized calcium (3.3 mg/dL; reference value 4.4-5.2) were decreased and alkaline phosphatase (313 U/L; reference value 35-129) was increased. Serum parathyroid hormone (268 pg/mL; reference value 13-54), 25(OH)D measured by radioimmunoassay (Diasorin kit) (less than 4.0 ng/mL; reference value 4.8-52.8), 1,25(OH)D (7.51 pg/mL; reference value 19.60-54.30), osteocalcin (32.9 ng/mL; reference value 11.3-37.0), N-telopeptide (NTx; 100 nMBCE/mMCr; reference value 14-81), urine calcium (0.6 mg/dL), and urine phosphorus (29.1 mg/dL) indicated vitamin D deficiency and secondary hyperparathyroidism.\nRadiologic examination findings: In spinal X-ray scanning, diffuse osteopenia was observed overall. Pseudofracture was not exhibited in femur, pelvic bone, and costal bone. In bone mineral density examination utilizing dual energy X-ray absorptiometry, severe diffuse osteopenia was observed with Z values of lumbar spine (L1-L4) (-5.4) and femoral neck (-4.0) (). In whole body bone scan, multiple increased uptakes including costal bone were exhibited and it was in agreement with the finding of osteomalacia ().\nClinical progress: In order to evaluate and find the causes of vitamin D deficiency in the patient, listening of medical history and environment investigation were carried out in detail. The patient had been vegetarian since 8 years ago; he had meals three times a day with general meals but he was vegan, the strictest type of vegetarian, who didn't eat meats, fish, eggs, and milk etc at all. He had a bowl of rice per meal and vegetables and legumes as side dishes. The patient hardly went out for the last 6 months and stayed and worked at home using internet. Therefore, we performed bone mineral density examination, serum hormone examination, and electrolyte examination in the patient who came into the hospital due to the walking impairment and were under examination in neurology department. Based upon the examination, the authors diagnosed osteomalacia caused by vitamin D deficiency due to undernutrition and lack of exposure to sunlight. The patient started taking calcitriol, 0.5 µg per day, and calcium carbonate, 1,000 mg per day. After a week, serum ionized calcium (4.0 mg/dL) and serum phosphorus (2.9 mg/dL) were observed to be increased. Serum ionized calcium was back to normal, 4.5 mg/dL, 12 days after the injection. As the patient got better after a week, bone biopsy was not carried out. We recommended him to have sufficient nutrition including vitamin D and to go out in order to be exposed to sunlight daily. The patient was prescribed calcitriol, 0.5 µg per day, and calcium carbonate, 1,000 mg per day, when he was discharged from the hospital. In follow up from out-patient clinic 3 months later, strength index, 5, was back to normal and pains at hip joint and walking impairment were improved. Serum calcium (8.7 mg/dL), phosphoric acid (4.3 mg/dL), ionized calcium (4.5 mg/dL), and 25(OH) D (5.9 ng/mL) were improved as well. Alkaline phosphatase and serum parathyroid hormone exhibited 391 U/L and 295 pg/mL, respectively.