Endocrine Abstracts

Introduction: Multiple Endocrine Neoplasia Type 1 (MEN1) is a rare, autosomal dominantly inherited syndrome that causes tumors of the endocrine glands [1]. This syndrome is most commonly associated with neuroendocrine tumors of the parathyroid glands, pituitary gland and pancreas [2].

Case: A 30-year-old woman was admitted to the Hospital of Lithuanian University of Health Sciences, Kaunas Clinics for unconsciousness and significant hypoglycaemia: 1.0 - 3.04 mmol/l.

Anamnesis: In 2016, the patient was examined for infertility. Hyperprolactinemia was diagnosed. Head MRI was performed to detect pituitary microadenoma, treatment with Cabergoline 0.25 mg/week was started. In 2017, an episode of the hypoglycaemic coma was observed. Due to recurrent unspecified hypoglycaemia, the patient was admitted to the Endocrinology Department.

Laboratory tests were performed (Table 1). GTT results were within the normal range. Thyroid US: hypoechoic masses: dorsal from the left lobe, 1.6x0.5 cm and dorsal from the right lobe 2x0.4 cm - possibly parathyroid adenomas. DXA scan: T value - 2.5; Z value -2.5. Conclusion: osteoporosis.

After evaluating multiple endocrine pathologies (prolactinoma, hyperparathyroidism, hypoglycaemia), MEN1 syndrome was diagnosed with the following outcomes:

1) Microadenoma hypophysis – prolactinoma. Secondary infertility

2) Parathyroid adenomas. Primary hyperparathyroidism. Secondary osteoporosis.

3) Insulinoma. Hypoglycaemia.

Parathyroid Scintigraphy Tc-MIBI + SPECT/CT: right and left parathyroid adenomas. Head MRI: 0.6x0.6 cm hypo-enhanced area on the left side of the adenohypophysis - pituitary microadenoma, without negative dynamics. Abdominal MRI: a possible neuroendocrine tumor - insulinoma in the body and tail of the pancreas. Genetic test: sequencing of 2-4 exons of the transcript encoded by the MEN1 gene was performed. A pathogenic change in the c.446-2A> T sequence was identified, and the diagnosis of MEN1 syndrome was confirmed. The patient underwent parathyroidadenomectomia subtotal, laparoscopic surgery to remove insulinoma. An abdominal MRI was performed 6 months later and two new neuroendocrine tumors were identified in the pancreas. Confirmed during scintigraphy. The patient underwent reoperation. After 1 year, there were no signs of recurrence of insulinoma and hyperparathyroidism, test results were in normal ranges.

Conclusion: This clinical case reflects the classic manifestation of MEN1 syndrome with the typical target organs: the parathyroid glands, pancreas, and pituitary gland. In addition, secondary symptoms of these diseases were hyperparathyroidism, infertility, hypoglycaemia and osteoporosis. Multiple endocrine disorders should lead to a suspicion of a diagnosis of MEN1. Therefore, precise laboratory, imaging tests of the target organs and genetic tests should be performed.