May 1981

Heterogeneity of Adult Hypophosphatasia Report of Severe and Mild Cases

Author Affiliations

From the Metabolic Bone Disease Laboratory, Section of Metabolic and Endocrine Disease, Department of Medicine, Medical College of Georgia, Augusta (Dr Weinstein), and the Division of Bone and Mineral Metabolism, Department of Medicine, The Jewish Hospital of St Louis, Washington University School of Medicine (Dr Whyte).

Arch Intern Med. 1981;141(6):727-731. doi:10.1001/archinte.1981.00340060035010

Two cases of women with adult hypophosphatasia illustrate the clinical spectrum and potential difficulties in the diagnosis of this condition. Both patients had subnormal serum alkaline phosphatase activity, absence of leukocyte alkaline phosphatase, increased amounts of urinary phosphoethanolamine, and normal levels of immunoreactive calcitonin and parathyroid hormone. In undecalcified bone biopsy specimens, the number of osteoblasts and the tetracycline-labeled calcification front were similar in the two patients, although the percentage of unmineralized bone matrix and the extent of osteoid-covered bone surface were different. Twenty years of bone pain, severe skeletal deformities, and a generalized increase of osteoid in one patient contrasted with an 18-month history of bone pain and patchy osteoid in the other. These cases suggest that adult hypophosphatasia is a heterogenous disorder and may be more common than previously realized.

(Arch Intern Med 1981;141:727-731)