Resolution of hypergastrinaemia after parathyroidectomy in multiple endocrine neoplasia syndrome type I (MEN type I).
The treatment of choice for gastric acid hypersecretion in MEN type I has now changed from total gastrectomy to the long-term administration of H2 receptor blockers or similar agents. However, the importance of parathyroidectomy for the concomitant hypercalcaemia is not fully realized. A case is reported of a subject with MEN type I, who was initially treated with parathyroidectomy and H2 receptor blockade. Following parathyroidectomy, there was a rapid fall of the markedly elevated gastrin levels to the upper limit of the normal range. During follow-up of 2.5 years, there has been no increase in serum gastrin, and the subject's gastric symptoms have resolved, despite the cessation of H2 blockade. Infusion of calcium to pre-operative levels and superimposed secretin stimulation after this period of time closely reproduced the pre-operative hypergastrinaemia. On screening, the subject's only child was found to have hypercalcaemia but normal serum gastrin levels and pituitary function; parathyroidectomy has been carried out. No abnormality of gastrin secretion has been found during follow-up. This case highlights the importance of early parathyroidectomy in this syndrome.