Sodyum Taurokolat Taşıyan Polipeptit Mutasyonuna Bağlı Transaminaz Yüksekliği

Abstract

Ailesel hiperkolanemi-2, SLC10A1 genindeki mutasyonların neden olduğu, konjuge safra tuzlarının plazmadan hepatositlere taşınmasındaki bozukluk ile sonuçlanan bir durumdur. Bunun nedeni, etkilenen gen tarafından kodlanan sodyum taurokolat kotransport polipeptididir. Gen ilk olarak 1994 yılında tanımlanmış olmasına rağmen hastalığın klinik özelliklerine ilişkin bilgiler sınırlıdır. Bildirilen birkaç vakada da hem klinik hem de laboratuvar bulguları farklılık göstermiştir. Bu yazımızda; tüm ekzon dizi analizi çalışmasıyla; ailesel hiperkolanemi-2 tanısı alan on iki yaşında bir kız hastayı sunuyoruz. Asemptomatik hipertransaminazemi nedeniyle getirilen hastaya, etiyolojiye yönelik kapsamlı çalışmalar sonucunda nedenin belirlenememesi üzerine genetik temelli tanı testleri yapıldı. Klinik olarak asemptomatik olan hastanın, laboratuvar incelemelerinde hiperkolanemi (safra asidi düzeyi 81.9 μmol/L) (açlık < 10 μmol/L, tokluk < 15 μmol/L) ve hipertransaminazemi mevcuttu. Hastalığın çok çeşitli fenotiplerle ortaya çıkabileceği ve altta yatan genetik mutasyon veya henüz tanımlanamayan mekanizmalara bağlı olarak laboratuvar bulgularının hastalar arasında farklılık gösterebileceği düşünülmektedir. Bu nedenle nedeni belirlenemeyen hipertransaminazemili hastalarda tanısal genetik incelemelerin yaygınlaştırılması önerilmektedir.

Keywords

• Safra asitleri ve tuzları
• Kolestaz
• Hiperkolanemi
• Sodyum taurokolat birlikte taşınan polipeptit

Sodium Taurocolate Cotransporting Polypeptide Mutation Associated Transaminase Elevation

Abstract

Familial hypercholanemia-2 is a condition caused by mutations in the human solute carrier family 10 member 1 (SLC10A1) gene, which results in the inability to transport conjugated bile salts from plasma to hepatocytes. This is due to the sodium taurocholate cotransport polypeptide encoded by the gene being affected. Although the gene was first described in 1994, there is limited knowledge on the clinical features of the disease. In the few reported cases, both clinical and laboratory findings have varied. We reported a twelve-year-old girl was diagnosed with familial hypercholanemia-2 through a whole gene exome sequencing study. She was brought in with asymptomatic hypertransaminasemia, and after comprehensive studies on etiology failed to detect the cause, genetic testing was done. The patient had no clinically abnormal findings but had hypercholanemia (bile acid level 81.9 μmol/L) (fasting < 10 μmol/L, postprandial < 15 μmol/L) and hypertransaminasemia in laboratory examinations. It is believed that the disease can present with a wide range of phenotypes, and laboratory findings may differ between patients depending on the underlying genetic mutation or mechanisms that have not yet been identified. Therefore, it is recommended to expand diagnostic genetic examinations in patients with hypertransaminasemia whose cause cannot be determined

Keywords

• Bile acids and salts
• cholestasis
• hypercholanemia
• Sodium taurocholate cotransporting polypeptide

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