Hypophosphatasia: A rare disease with an easy diagnosis and available therapy

Czech version

Authors: Šumník Zdeněk; Souček Ondřej
Authors‘ workplace: Pediatrická klinika, 2. lékařská fakulta, Univerzita Karlova a FN v Motole, Praha
Published in: Čes-slov Pediat 2023; 78 (6): 325-329.
Category: Comprehensive Report
doi: https://doi.org/10.55095/CSPediatrie2023/047

Overview

Hypophosphatasia (HPP) is a disease characterized by predominant skeletal involvement and multiple systemic manifestations due to reduced activity of tissue-non-specific alkaline phosphatase (ALP) in the serum. The incidence of severe forms of HPP in European populations is estimated at 1:300 000, with the frequency of milder forms being significantly more common, around 1:6300. HPP is one of the clinically heterogeneous diseases, leading symptoms typically vary by age at manifestation. The most severe, life-threatening forms are the neonatal and infantile forms. HPP can also manifest later in life, most commonly causing skeletal deformities, poorly healing fractures or arthropathy. Until 2015, treatment of these patients was symptomatic. The situation has changed with the development and availability of recombinant ALP (asfotase alfa), the indication for which is HPP, in which the first symptoms of the disease appeared before the age of 18 years, in order to treat the bone manifestations of the disease. This review summarizes the current knowledge on the diagnosis, therapy and prognosis of this disease and illustrates the most commonly used differential diagnostic procedures when assessing low ALP or clinical symptoms suspicious for HPP. Early diagnosis represents the most important preventive tool against the development of HPP complications.

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