Hypophosphatasia: the clinical description of 3 cases of the disease with the molecular-genetic verification of the diagnosis

Hypophosphatasia is a rare hereditary rickets-like disease resulting from the impaired activity of tissue-specific alkaline phosphatase encoded by the ALPL gene. A few forms of this pathology are distinguished depending on the severity of its clinical picture and the age at which its symptoms begin to manifest themselves. The main clinical signs of the disease are skeletal deformations, muscular hypotonia, and respiratory insufficiency in the early childhood as well as the retardation of the physical and motor development and early loss of the teeth In the mature age, such patients suffer from stress fractures, muscle pain, calcification of the ligaments and joints. The biochemical markers of hypophosphatasia are the low blood alkaline phosphatase level and the high urinary phosphoethanolamine level. Also, the severe forms of the disease are associated with hypercalcemia, hyperphosphatemia, and the low parathormone level. The authors describe the patients presenting with Hypophosphatasia of different severity in whom the molecular-genetic verification of the diagnosis was undertaken for the first time in this country.

ALPL, rickets-like disease, hypophosphatasia, ALPL gene, alkaline phosphatase, inorganic pyrophosphates, phosphoethanolamine

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