The authors describe a female patient with large parathyroid gland adenoma presenting with clinical symptoms of primary hyperparathyroidism and severe hypercalcaemia. Before planned surgical treatment the patient spontaneously developed clinical symptoms of tetany. Hypocalcaemia was confirmed by laboratory test. The reason turned out to be spontaneous necrosis of the parathyroid adenoma, resulting in remission of hyperparathyroidism. After stabilization of calcium levels, the necrotic adenoma was removed and histopathological examination revealed necrotic adenoma with only occasional vital adenoma cells. During the next follow-up the patient was without any subjective complaints and her state was stable. This phenomenon, yet described in the literature in past, belongs to unusual findings.

        Key words: Hyperparathyroidism - Adenoma - Spontaneous necrosis - Remission