| Hyperthyroidism is one of the causes for elevated alkaline phosphatase. In the treatment of hyperthyroidism, if it appears that the progressive rise of alkaline phosphatase is accompanied by bone pain, we cannot rule out the possibility of osteomalacia, which deserves attention. With the further study of metabolic bone disease, patients with osteomalacia gradually increase, and the causes include deficiency of vitamin D, vitamin D absorption and metabolic disorders, kidney disease (nephrotic syndrome, chronic renal failure, renal tubular acidosis, fanconi syndrome, etc.), as well as hereditary and tumorous low phosphorus osteomalacia, and other causes including heavy metal poisoning, high fluoride intake, certain drugs and so on. However, osteoporosis is more common in patients with hyperthyroidism, and it is rare to for hyperthyroidism patients to have osteomalacia. As it is rarely reported, it is easy to miss diagnosis and misdiagnosis. We report a case of hyperthyroidism with progressive elevation of alkaline phosphatase (ALP) and systemic bone pain after oral administration of methimazole, and alkaline phosphatase decreased and bone pain disappeared after oral administration of calcitriol. Therefore, during the treatment of hyperthyroidism, combined with foreign literature reports, we considered the possibility of osteomalacia, and closely observed the changes of alkaline phosphatase in the patients. After active symptomatic treatment, the symptoms of osteomalacia were significantly alleviated. So we should pay attention to the changes of alkaline phosphatase and its clinical characteristics, so as to make sure whether there is osteomalacia and to treat it as soon as possible. |