FAMILIAL IDIOPATHIC HYPERPHOSPHATASIA A STUDY OF TWO YOUNG SIBLINGS TREATED WITH PORCINE CALCITONIN

A study of two siblings with a severe infantile form of familial idiopathic hyperphosphatasia is reported. A girl aged one year was followed for two years while receiving intermittent treatment with porcine calcitonin. This induced a clinical remission, a reduction ofboth the high serum level of alkaline phosphatase and the raised urinary excretion ofhydroxyproline, and a remarkable improvement in bone structure as seen radiologically. Her sister aged two months received porcine calcitonin for three weeks, during which clinical improvement, no change in the serum level of alkaline phosphatase and a marked decrease of the excretion of hydroxyproline were recorded. A rare disorder of bone in childhood has been reported in the literature under different names. Its main features are progressive skeletal deformity with generalised conversion of long bones to coarsely tra-beculated radiolucent widened bone, coxa vara, pro-tusio acetabuli and diaphysial bowing, and high levels of both serum alkaline phosphatase and urinary excretion of hydroxyproline. Chronic idiopathic orfamilial hyper-phosphatasia, the term coined by Caffey in 1961, has gained wide acceptance although there is general agreement that the raised serum phosphatase is only secondary to the bone disorder. Other proposed names are Osteitis deformans in children (Choremis et al. 1958), Hyperostosis corticalis (Swoboda 1958), Osteochalasia desmalis famiiaris (Fanconi et al. 1964) and Familial osteoectasia (Bakwin et al. 1964). In 1973 Caffey reviewed fourteen patients des-cribed in the English literature with this type of bon