Co-existence of hyperparathyroidism, hypergastrinaemia and multiple gastric carcinoids is not always due to incomplete expression of the MEN-1 syndrome.

Until recently, the association of primary hyperparathyroidism and gastric carcinoid, with or without hypergastrinaemia, had been considered an incomplete form of multiple endocrine neoplasia type 1. This is because it seemed unlikely that the rare joint appearance of these diseases could occur only by chance. It is now possible to evaluate the pathogenetic involvement of the multiple endocrine neoplasia type 1 gene in many, apparently sporadic, clinical conditions. This is a case report of a female mimicking multiple endocrine neoplasia type 1 due to the presence of hyperparathyroidism, gastric carcinoid, and hypergastrinaemia. However, involvement of the MEN-1 gene (exons 2-10) was not detected, whereas hypergastrinaemia was attributed to a chronic atrophic gastritis.