Influence of disodium etidronate on Paget's disease of bone.

The use of agents that decrease bone resorption, notably the calcitonins, diphosphonates and mithramycin, has been shown to result in symptomatic and/or biochemical improvement in patients with Paget's disease of bone (osteitis deformans). The effects of short-term (6 months), low-dose (5 mg/kg body mass/d) etidronate disodium, a diphosphonate compound at present subject to registration in this country, on the clinical and laboratory manifestations of this disorder were examined. Marked symptomatic improvement was noted in 70% of patients, while biochemical parameters of bone turnover, namely serum alkaline phosphatase level (44%) and urine hydroxyproline excretion (56%), decreased significantly (P less than 0.001). A technetium-99m bone scan revealed an impressive reduction in uptake of isotope in 50% of patients. The drug was well tolerated and no adverse reactions (clinical, biochemical or haematological) were evident. It is concluded that short-term low-dose etidronate disodium affords a convenient and effective therapeutic alternative in patients with symptomatic Paget's disease.