Osteomalacia
Osteomalacia is a disease characterized by soft and weak bones. In children the condition is known as rickets, and leads to defects in growth and development.
Causes
Calcium and phosphorus are vital minerals for normal bones, and vitamin D is a major regulator of bone materials. Deficient diet, intestinal absorption problems, or inability of the body to use these nutrients can cause osteomalacia.
The body’s primary source of Vitamin D is sunlight; therefore low sunlight exposure is an important cause of osteomalacia. In the US most people get sufficient exposure to sunlight, so osteomalacia is a rare disease. Moreover, dairy products sold for human consumption are rich in calcium, are often fortified with vitamin D.
People at risk for developing osteomalacia are:
- those living in far northern parts of the world (Alaska, Scandinavia), due to shorter sunlight hours;
- the elderly who live in long-term care;
- people who are lactose intolerant or do not ingest enough dairy products;
- people with dark skin or those who use strong sunscreens that block the absorption of the rays of the sun.
Other causes for osteomalacia include certain surgeries (gastric or intestinal bypass), celiac disease, kidney or liver disorders, some drugs, and alcoholism.
Symptoms
Completely silent at early stages, osteomalacia may cause a variety of symptoms as the disease progresses: bone pain, muscle weakness, muscle cramps, numbness or tingling, abnormal heart rate (due to low calcium levels), fatigue, bone deformities, growth problems (in children), and in severe cases, bone fractures.
Tests and diagnosis
- Blood tests: vitamin D, creatinine, calcium, and phosphate levels.
- Bone x-rays and a bone density test to detect pseudofractures, bone loss, and bone softening.
- Bone biopsy reveals bone softening.
Treatment
Treatment is adapted to the individual case, the severity of symptoms, and the presence of any underlying diseases or complications.
When osteomalacia arises from a dietary or sunlight deficiency, replenishing low levels of vitamin D and calcium usually cures the condition.
Patients take oral vitamin D supplements for several weeks or months. Less commonly, vitamin D is given as injection. Supplements of calcium or phosphorus are also given if the patient's body is deficient in these minerals.
Prevention
Exposure to sunlight and a diet rich in vitamin D can help prevent osteomalacia. Vitamin D is found in large amounts in fortified dairy products (milk, yogurt), cereal, bread, egg yolks, oily fish (salmon, mackerel, and sardines), and cod liver oil.
Washington University Page on Osteomalacia
Difference Between Osteoporosis, Hyperparathyroidism, and Osteomalacia
Last updated: Nov 1, 2011
