Adrenocorticotropin-independent Cushing's syndrome in pregnancy related to overexpression of adrenal luteinizing hormone/human chorionic gonadotropin receptors.

Cushing's syndrome during pregnancy is rare, and rather than being of pituitary origin most patients exhibit ACTH-independent adrenal hypercortisolism. In some cases the syndrome has spontaneously resolved post partum, suggesting the presence of a pregnancy-associated stimulatory factor(s). We describe a case with aberrant adrenal LH/hCG receptors in a large adrenal tumor as a possible explanation for cortisol hypersecretion and tumor growth in Cushing s syndrome during pregnancy. A 27-yr-old woman presented with hypertension and diabetes mellitus in early pregnancy. Investigations revealed hypercortisolemia, suppressed ACTH-levels, and a 6.4- cm right adrenal tumor. The tumor was successfully removed by laparoscopy at 26th week of pregnancy. Hypercortisolism and hypertension resolved post-operatively. The tumor displayed higher LH/hCG receptor mRNA and protein positivity than adjacent normal adrenal tissue as examined by in situ hybridization and immunocytochemistry. High physiological levels of hCG, in conjunction with aberrant adrenal LH/hCG receptor overexpression, may have contributed to the development of Cushing's syndrome in pregnancy.