The evolving course of HNF4A hyperinsulinaemic hypoglycaemia—a case series
Article first published online: 12 DEC 2013
© 2013 The Authors. Diabetic Medicine © 2013 Diabetes UK
Volume 31, Issue 1, pages e1–e5, January 2014
How to Cite
Diabet. Med. 31, e1–e5 (2014)
- Issue published online: 12 DEC 2013
- Article first published online: 12 DEC 2013
- Accepted manuscript online: 24 JUN 2013 09:41AM EST
- Manuscript Accepted: 18 JUN 2013
Hepatocyte nuclear factor 4 alpha (HNF4A) gene mutations have a well-recognized role in maturity-onset diabetes of the young and have recently been described in congenital hyperinsulinism. A biphasic phenotype has been postulated, with macrosomia and congenital hyperinsulinism in infancy, and diabetes in young adulthood. In this case series, we report three children with HNF4A mutations (two de novo) and diazoxide-responsive congenital hyperinsulinism, highlighting the potential for ongoing diazoxide requirement and the importance of screening for these mutations even in the absence of family history.
All patients presented with macrosomia (mean birthweight 4.26 kg) and hyperinsulinaemic hypoglycaemia soon after birth (median age 1 day). All three (age range 7 months to 11 years 10 months) remain on diazoxide therapy, with dose requirements increasing in one patient. There was no prior family history of diabetes, neonatal hypoglycaemia or macrosomia. Parents were screened for HNF4A mutations post-diagnosis and one father was subsequently found to have maturity-onset diabetes of the young.
This case series follows the evolving course of three patients with confirmed HNF4A-mediated congenital hyperinsulinism, highlighting (1) the variable natural history of these mutations, (2) the potential for prolonged diazoxide requirement, even into adolescence, and (3) the need for screening, regardless of family history.