1. DR. M. KRISHNA VASUDEV OSTEOMALACIA 2. INTRODUCTION Osteomalacia is the softening of the bones caused by defective bone mineralization secondary to inadequate levels of available phosphate and calcium, or because of overactive resorption of calcium from the bone which can be caused by hyperparathyroidism (which causes hypercalcemia). Osteomalacia in children is known as rickets, and because of this, use of the term "osteomalacia" is often restricted to the milder, adult form of the disease. Signs and symptoms can include diffuse body pains, muscle weakness, and fragility of the bones. 3. CAUSES Osteomalacia is a generalized bone condition in which there is inadequate mineralization of the bone. Many of the effects of the disease overlap with the more common osteoporosis, but the two diseases are significantly different. There are two main causes of osteomalacia: 1. insufficient calcium absorption from the intestine because of lack of dietary calcium or a deficiency of, or resistance to, the action of vitamin D; and 2. phosphate deficiency caused by increased renal losses. 4. CAUSES dietary deficiency of vitamin D + lack of solar irradiation deficiency of metabolism of vitamin D chronic renal disease (most common cause) 1-hydroxylation of 25-vitamin D renal tubular disorder (vitamin D resistant rickets): high level of phosphorus in urine X linked hypophosphatemia chronic liver disease: hepatocellular: 25-hydroxylation vitamin D biliary: abnormal gut absorption administration of phenobarbital (alternate liver pathway) 5. CAUSES decreased absorption of vitamin D malabsorption syndromes such as Crohn's partial gastrectomy (self-restriction of fatty foods) decreased deposition of calcium in bone diphosphonates Other causes Tumour induced osteomalacia Cadmium poisoning Itai-itai disease 6. SIGNS AND SYMPTOMS Diffuse joint and bone pain (especially of spine, pelvis, and legs) Muscle weakness Difficulty walking, often with waddling gait Hypocalcemia (positive Chvostek sign) Compressed vertebrae and diminished stature Pelvic flattening Weak, soft bones Easy fracturing Bending of bones 7. SIGNS AND SYMPTOMS Osteomalacia in adults starts insidiously as aches and pains in the lumbar (lower back) region and thighs before spreading to the arms and ribs. The pain is symmetrical, non-radiating and accompanied by sensitivity in the involved bones. Proximal muscles are weak, and there is difficulty in climbing up stairs and getting up from a squatting position. As a result of demineralization, the bones become less rigid. Physical signs include deformities like triradiate pelvis and lordosis. The patient has a typical "waddling" gait. However, these physical signs may derive from a previous osteomalacial state, since bones do not regain their original shape after they become deformed. 8. SIGNS AND SYMPTOMS Pathologic fractures due to weight bearing may develop. Most of the time, the only alleged symptom is chronic fatigue, while bone aches are not spontaneous but only revealed by pressure or shocks. It differs from renal osteodystrophy, where the latter shows hyperphosphatemia. 9. LAB FINDINGS Biochemical features are similar to those of rickets. The major factor is an abnormally low vitamin D concentration in blood serum. Major typical biochemical findings include: Low serum and urinary calcium Low serum phosphate, except in cases of renal osteodystrophy Elevated serum alkaline phosphatase (due to an increase in compensatory osteoblast activity) Elevated parathyroid hormone (due to low calcium) Furthermore, a technetium bone scan will show increased activity (also due to increased osteoblasts). 10. Condition Calcium Phosphat e Alkaline Phosphat e Parathyroid hormone Special features Osteopeni a Unaffecte d Unaffecte d Normal Unaffected Decrease d bone mass Osteoporo sis Unaffecte d Unaffecte d Elevated Unaffected Thick dense bones Osteomala cia/Rickets Decrease d Decrease d Elevated Elevated Soft bones Osteitis fibrosa cystica Elevated Decrease d Elevated Elevated Brown tumors Pagets disease unaffecte d decreased variable unaffected Abnormal bone structure COMPARISION OF CONDITIONS 11. RADIOLOGY diffuse demineralization: osteoporotic-like pattern may show a characteristic smudgy "erased" or "fuzzy" type of demineralization coarsened trabeculae insufficiency fractures Pseudofractures (loosers zone) articular manifestations (uncommon) rheumatoid arthritis-like picture osteogenic synovitis ankylosing spondylitis-like picture 12. TREATMENT Nutritional osteomalacia responds well to administration of 10,000 IU weekly of vitamin D for four to six weeks. Osteomalacia due to malabsorption may require treatment by injection or daily oral dosing of significant amounts of vitamin D. Calcitriol supplement for CKD. 13. Treatment Exercise Exercise helps to strengthen the bones, especially weight- bearing exercise (anything that involves walking or running). However, you should avoid intensive exercise while any fractures or cracks in the bones are healing. Sunlight Where possible, going outside and exposing your arms and face to sunlight is the best way to get vitamin D. From June to August just 15 minutes a day is generally enough. Dont allow your skin to go red and take care not to burn, particularly in strong sunshine and if you have fair or sensitive skin. Diet and nutrition A diet that includes vitamin D and calcium can help, but this wont prevent the condition by itself. Nevertheless, a diet that provides vitamin D is especially important if you dont get enough exposure to sunlight. - See more at: http://www.arthritisresearchuk.org/arthritis- information/conditions/osteomalacia/self-help-and-daily- living.aspx#sthash.RnEHUPBb.dpuf 14. All the back benchers can get up now.. The class is over Thank you