TRANSIENT NEONATAL DIABETES CAUSED BY ACTIVATING NOVEL KCNJ11 GENE MUTATION AND SUCCESSFULL TRANSFER TO SULPHONYLUREA THERAPY

Autori:

Gordana Stipančić, Marija Požgaj Šepec, Lavinia La Grasta Sabolić

Sažetak
Neonatalni diabetes mellitus (NDM) rijetka je monogenska forma dijabetesa koja se klinički prezentira uglavnom do 6. mjeseca života. Javlja se u obliku trajnog i prolaznog NDM-a. Dok je u trajnom NDM-u liječenje nužno cijeli život, u prolaznom NDM-u nakon nekoliko tjedana ili mjeseci liječenja dolazi do remisije, a samo oko 50% oboljelih doživi ­relaps bolesti tijekom adolescencije ili u ranoj odrasloj dobi. Mutacije ABCC8 ili rjeđe KCNJ11-genâ koji kodiraju pod­jedinice kalijeva kanala (KATP-kanal) ovisnog o adenozin trifosfatu uzrok su bolesti u manje od 30% oboljelih. Prikazujemo svoju bolesnicu s prolaznim NDM-om uzrokovanim novom aktivirajućom mutacijom KCNJ11-gena s učinkom na Kir6.2-podjedinicu KATP-kanala i uspješno prevođenje s inzulinske terapije na terapiju sulfonilurejom. Genetička analiza učinjena je u 22. godini života, 12 godina nakon relapsa bolesti te nakon 10 godina inzulinske terapije. Nakon 3 mjeseca terapije peroralnim preparatom sulfonilureje normalizirala se razina HbA1c, a potom i razina inzulina te C-peptida. Zaključak: Potvrdom monogenskog oblika dijabetesa genetička analiza može promijeniti terapijski pristup s pozitivnim učinkom na kontrolu i tijek bolesti, kvalitetu života te otvara mogućnost genetičkog savjetovanja.
Summary

Neonatal diabetes mellitus (NDM) is a rare monogenic form of diabetes that usually presents within the first six months of life. It occurs in the form of transient and permanent NDM. Permanent NDM requires life-long treatment while TNDM resolves few weeks or months after treatment initiation, with relapse occuring only in around 50% of patients ­during their adolescence or young adult life. Mutations in ABCC8, or less often in KCNJ11 gene (coding subunit of the ATP-sensitive potassium channel (KATP channel)) cause the disease in less than 30% of all patients. We present our female patient with transient NDM caused by a novel activating KCNJ11 mutation in the Kir6.2 subunit of the K-ATP channel and her successfull transfer from insulin to sulphonylurea therapy. Genetic testing was done at the age of 22 years, 12 years after disease relapse and ten years of insulin treatment. Three months after transfer to sulphonylurea therapy HbA1c levels normalised, followed by normalisation of C-peptide and insulin values as well. Conclusion: Using genetic analysis to confirm monogenic form of diabetes changes the therapeutical approach with positive effect on disease control and course and opens the possibility of genetic counseling.