Bone marrow disorders | Multiple myeloma |
| Myelodysplasia |
| Systemic mastocytosis |
| Thalassemia |
Endocrine or metabolic diseases | Acromegaly |
| Anorexia nervosa |
| Cushing syndrome |
| Diabetes mellitus type 1 |
| Hypercalcemia |
| Hyperparathyroidism |
| Hyperprolactinemia |
| Hyperthyroidism |
| Hypopituitarism |
Other conditions | Chronic kidney disease |
| History of organ transplantation |
| Hypercalciuria |
| Immobilization (e.g., paraplegia, quadriplegia, or muscular dystrophy) |
| Inadequate calcium uptake |
| Malabsorption (e.g., celiac disease) |
| Rheumatoid arthritis |
| Secondary hyperparathyroidism due to renal disease |
| Vitamin D deficiency |