Causes
Rickets and osteomalacia result when there is a vitamin D deficiency in the body. This may occur when:
- The supply of vitamin D from the diet or sun exposure is inadequate.
- The metabolism of vitamin D is abnormal.
- Tissue is resistant to the action of vitamin D.
Vitamin D regulates calcium absorption in the body. It also controls levels of calcium and phosphate in bone. Vitamin D is absorbed in the intestines from food. Vitamin D is also produced by the skin during exposure to sunlight.
Most often, rickets and osteomalacia are caused by a deficiency of vitamin D. This can result from:
-
Insufficient vitamin D in the diet. In children, this may be related to:
- Insufficient consumption of vitamin D-fortified milk
- Insufficient intake of vitamin D supplements to children being breastfed or to children who are lactose intolerant
- Lack of exposure to sunlight.
Less often, rickets and osteomalacia can be caused by other disorders that affect vitamin D absorption, metabolism, or action in the body such as:
-
Kidney problems:
- A hereditary disorder of the kidney called vitamin D-resistant rickets
- Renal tubular acidosis—a nonhereditary kidney disorder which causes bone calcium to dissolve
- Chronic kidney failure
- Long-term kidney dialysis
- Diseases of the small intestines with malabsorption
- Disorders of the liver or pancreas disease
- Cancer
-
Certain drugs, such as:
- Certain seizure medications, such as phenytoin or phenobarbital
- Acetazolamide
- Ammonium chloride
- Disodium etidronate
- Fluoride treatment
-
Toxicity or poisoning from:
- Cadmium
- Lead
- Aluminum
- Outdated tetracycline
Risk Factors
A risk factor is something that increases your chance of getting a disease or condition. Risk factors for rickets/osteomalacia include:
-
Age in children: 6 to 24 months old
- Either the child is consuming breast milk (from a mother who is deficient in vitamin D) or milk not fortified with vitamin D.
- Age in adults: 50-80 years
- Lactose intolerance with inadequate intake of vitamin D-fortified milk
- Family history of rickets
- Race: Black, especially in association with breastfeeding