Biyokimyasal Olarak Düşük Alkalen Fosfataz Düzeyi Saptanan Bireylerin Hipofosfatazya Açısından Değerlendirilmesi

Abstract

Hypophosphatasia (HPP) (OMIM 146300, 241500, 241510) is a rare, inherited disease characterized by bone and tooth mineralization disorder resulting from decreased non-tissue-specific alkaline phosphatase activity. There are seven forms of the disease described so far. The form in which only the teeth are affected is called "odontohypophosphatasia"; this is the most common and probably the mildest form. Other types of the disease are named according to age groups and prognosis. These are "adult hypophosphatasia," "mild childhood hypophosphatasia," "severe childhood hypophosphatasia," "infantile hypophosphatasia," "prenatal benign hypophosphatasia" and "lethal perinatal hypophosphatasia." Despite developing laboratory techniques and genetic analysis methods, the diagnosis of HPP is delayed, especially in mild disease forms, because muscle, joint, and bone pain, which is one of the common symptoms of the disease, is confused with more common diseases such as rheumatoid arthritis, fibromyalgia, osteogenesis imperfecta, Paget's disease, rickets, and osteomalacia. For this reason, it is essential to know about the disease and to suspect it for diagnosis. Another reason for the delay in diagnosis; clinicians are more accustomed to high ALP enzyme levels, and low ALP values are overlooked. ALP level was measured between 2014 and 2022 in Hacettepe University Children's and Adult Hospitals, and patients with values below the lower limit determined according to age groups were included. A total of 48 patients agreed to participate in the study. Of these patients, 34 (70.8%) were female, and 14 (29.2%) were male. The median ALP result of the patients included in the study was 28 IU/L. When the relationship between ALP and age was examined, a negative relationship was found between the two variables, which was significant at the p<0.01 level. When the relationship between ALP and gender was examined, ALP levels were found to be higher in men than in women, and the relationship between the two variables was significant at the p 0.01 level. The median PLP value was 27.6 µg/L, and the median PEA value was 49.35 µmol/g crea. There were 12 patients (25%) with high PLP results and 21 patients (43.7%) with high PEA results. Seven patients (14.5%) had high results for both PLP and PEA. The relationship between PEA and PLP results was examined, and a positive correlation was found between the two variables at the p 0.01 level. Bone pain in 35.4%, joint pain in 29.2%, tooth fracture in 18.8%, tooth loss in 10.4%, tooth fracture in 10.4%, and 10.4% had a history of bone fractures. When the relationship between patient complaints and ALP, PLP, and PEA results were examined, the relationship between tooth fracture history and ALP was found to be significant at the p 0.002 level, and the relationship was found to be negative. There was no significant correlation between the ALP, PLP, and PEA results of patients with dental caries and tooth loss. Still, the mean of ALP was 15.3 IU/L in patients with these complaints, while the mean of ALP was 25.57 IU/L in patients without these complaints; a numerical difference was observed. When the relationship between the complaint of bone pain and gender was examined, 16 of 34 (70.8%) female patients had bone pain, while only 1 of 14 (29.2%) male patients had bone pain. This relationship was found to be significant at the p 0.009 level. ALPL gene sequence analysis was performed in 31 of the 48 patients who participated in the study. Heterozygous mutations were detected in 25 patients and no mutation was detected in the remaining six patients.