A rare genetic bone disorder involving abnormal loss of bone mineralization and remineralization, broadened bone shafts and high levels of alkaline phosphatase in the blood.
* Blue sclerae * Deafness * Growth deficiency * Enlarged bone ends * Broadened bone shafts * Bowed bone shafts * Pigeon breast * Kyphoscoliosis * Short stature * Walking difficulty * Enlarged head * Dental caries * Increased blood level of alkaline phosphatase * Increased urine level of leucine-amino acid peptidase * Increased urine level of uric acid * Increased blood level of uric acid * Increased blood level of leucine-aminopeptidase * Incrdased blood level of hydroxyproline
The disease occurs worldwide, but is more common in Europe, Australia, and New Zealand, where it’s seen in up to 5% of the elderly population. Although its exact cause is unknown, one theory holds that early viral infection causes a dormant skeletal infection that erupts many years later as Paget’s disease. Genetic factors are also suspected.
Primary treatment consists of drug therapy and includes one of the following: * Calcitonin (subcutaneously or intranasally) is used to retard bone resorption (which relieves bone lesions) and reduce levels of serum alkaline phosphate and urinary hydroxyproline secretion. Although calcitonin therapy requires long-term maintenance, improvement is noticeable after the first few weeks of treatment. * Bisphosphonates, such as etidronate, alendronate, pamidronate, tiludronate, and risedronate, produce rapid reduction in bone turnover and relieve pain. They also reduce serum alkaline phosphate and urinary hydroxyproline secretion. Therapy produces noticeable improvement after 1 to 3 months. * Plicamycin, a cytotoxic antibiotic, is used to decrease calcium, urinary hydroxyproline, and serum alkaline phosphatase. It produces remission of symptoms within 2 weeks and biochemical improvement in 1 to 2 months. Plicamycin is used to control the disease and is reserved for severe cases with neurologic compromise and for those resistant to other therapies. However, it may destroy platelets or compromise renal function. Orthopedic surgery is used to correct specific deformities in severe cases, reduce or prevent pathologic fractures, correct secondary deformities, or relieve neurologic impairment. Joint replacement is difficult because bonding material (methyl methacrylate) doesn’t set properly on pagetic bone. Other treatment varies according to symptoms. Analgesics or nonsteroidal anti-inflammatory drugs may be given to control pain.