My 18 year old son was born with nesidioblastosis and had 95% of his pancreas removed at nine days of age. There was no information available in 1984 about his condition, and we are very lucky that he is an incredibly fit young man who has never had any problems since the day of his operation. He does not have diabetes and doesn’t need enzymes, but I wonder about the future. He has an annual blood sugar and liver function test which are normal. Is this enough? I also wonder as his mother whether I passed on a faulty gene or caused his problem.

Nesidioblastosis, which is now called PHHI or Persistent Hypeinsulinemic Hypoglycemia of Infancy, is currently subdivided into a diffuse form and a focal adenomatous form. Your son’s excellent post-operative progress suggests that he was one of approximately 30% in the latter group.

Because of the rarity of this condition, about 1:50,000 births the genetics is still not well understood. Most cases though are sporadic with only some 5% being familial. There have been some interesting recent developments in the understanding of the inheritance especially of the focal variety. A group of investigators in Paris have shown that in these case there are losses of maternal alleles in the short arm of chromosome 11, an area that contains two of the four genes primarily involved in the hyperinsulinism namely SUR-1 (Sulphonyl Urea Receptor-1) and KIR6.2 at the same time there is also a paternal contribution from other abnormalities in the SUR-1 gene.

I don’t think that your son really needs any additional investigation, although of course it would be interesting to determine radiologically the extent to which his pancreas has redeveloped. I also think it unlikely that he would pass this on to his children; but when the time comes for him to consider starting a family of his own, he should contact the genetics group at the hospital where he was diagnosed to catch up with any recent developments in this particular field.

DOB