GUIDELINES ON THE DIAGNOSIS AND MANAGEMENT OF X-LINKED HYPOPHOSPHATEMIA

Abstract

X-linked hypophosphatemia (XLH) is the most common cause of rickets related to inherited renal phosphate wasting. XLH is associated with lower limb deformities, pain, poor mineralization of the teeth, and disproportionate short stature in children as well as hyperparathyroidism, osteomalacia, enthesopathies, osteoarthritis, and pseudofractures in adults. The characteristics and severity of XLH vary between patients. Because of its rarity, the diagnosis and specific treatment of XLH are frequently delayed, which has a detrimental effect on patient outcomes. The diagnosis of XLH is based on signs of rickets and/or osteomalacia in association with hypophosphatemia and renal phosphate wasting in the absence of vitamin D or calcium deficiency. Whenever possible, the diagnosis should be confirmed by molecular genetic analysis or measurement of levels of fibroblast growth factor 23 (FGF23) before treatment. An evidence-based guideline was published for recommendation on the diagnosis, treatment, and follow-up of XLH by a multidisciplinary team organized by a metabolic bone disease expert. In this article, the current recommendations - based on the published guideline was summarized and adapted for our country.

Keywords

• X-linked hypophosphatemia,XLH,rickets,hypophosphatemic rickets,PHEX,concensus,guidelines,treatment,conventional,burosumab

X’E BAĞLI HİPOFOSFATEMİDE TANI VE TEDAVİ UZLAŞISI

Abstract

X’e bağlı hipofosfatemi (XLH) kalıtsal renal fosfat kaybına bağlı raşitizmin en sık nedenidir. Çocuklarda alt ektremite deformiteleri, orantısız boy kısalığı, ektremite ağrısı, diş problemlerinin yanı sıra erişkin yaş grubunda hiperparatiroidi, osteomalazi, entesopati, osteoartrit ve psödofraktürlere neden olur. Hastalar arasında hastanın klinik seyri ve etkilenme düzeyi farklılıklar gösterebilir. XLH nadir bir hastalık olması nedeniyle hastalığın tanısı sıklıkla gecikmekte ve tedavi gecikmesinin hasta sonlanımına olumsuz etkileri bulunmaktadır. XLH; D vitamini eksikliği/ hipokalsemi veya hiperparatriodinin eşlik etmediği renal fosfat kaybına bağlı gelişen hipofosfatemi ve raşitizm durumunda akla gelmelidir. Mümkün olduğu durumlarda tanı, moleküler genetik testler ile veya tedavi öncesi alınan fibroblast growth factor 23 (FGF23) ölçümü ile doğrulanmalıdır. Metabolik kemik hastalıkları konusunda uzman hekimlerin önderliğinde multidisipliner bir ekip tarafından kanıta dayalı olarak hazırlanıp 2019 yılında yayınlanan uzlaşı raporu ile XLH hastalarının tanı ve tedavi kriterleri belirlenmiştir. Yazımızda bu uzlaşı raporu temel alınarak ülkemiz için XLH’de tanı, tedavi ve takip prensipleri verilmiştir.

Keywords

• X’e bağlı hipofosfatemi,XLH,raşitizm,hipofosfatemik raşitizm,PHEX,uzlaşı,rehber,tedavi,konvasiyonel,burosumab

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