The role of radiography in the diagnosis of different forms of hypophosphatasia: a clinical case

Hypophosphatasia is a rare metabolic disorder characterized by mutations in the ALPL gene and reduced activity of tissue-nonspecific alkaline phosphatase, leading to impaired mineralization of bone tissue and teeth. Clinical manifestations depend on the age at onset and the severity of the disease. In the severe perinatal and infantile forms, the following features are observed: marked skeletal hypomineralization, chest wall deformities, respiratory insufficiency, pyridoxine-dependent seizures, hypercalcemia, nephrocalcinosis, craniosynostosis, and a high risk of mortality. This article describes the characteristic radiographic features of various forms of the disease and provides a differential diagnosis with rickets. Clinical observations of two patients — one with the perinatal form and one with the childhood form of hypophosphatasia — are presented; both were diagnosed using laboratory, molecular genetic, and radiographic methods. It is noted that accurate interpretation of radiographic signs in different forms of hypophosphatasia can be crucial for timely diagnosis, initiation of therapy, and subsequent monitoring of treatment efficacy.

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