Endocrine Abstracts

Background: The diagnostic process to unveil the underlying cause of endogenous Cushing’s syndrome (CS) is often challenging. Sometimes, atypical manifestation of the disease or only periodic hypercortisolaemia with spontaneous resolutions are observed and make the diagnosis even more difficult. Although it is common in primary pigmented nodular adrenocortical disease (PPNAD), pituitary corticotroph adenoma can manifest itself as cyclic Cushing’s syndrome as well.

Case description: We present the difficulties that came with the patient with previously diagnosed primary pigmented nodular adrenal disease (PPNAD) and conflicting hormonal and radiological findings a few years later. A 33-year-old female with almost 10-year-long history of intermittent Cushing’s syndrome and no family history was first admitted for endocrinological evaluation in 2010. As a result, she underwent unilateral adrenalectomy because of an overt, apparently ACTH-independent, Cushing’s syndrome with hyperandrogenism and left adrenal hyperplasia. Histological examination revealed the diagnosis of PPNAD. Although being scheduled for right adrenalectomy, she moved on without any additional treatment. Despite repeated search, no other components of Carney’s complex had ever been discovered. Since 2015, cushingoid features had been getting more florid. Meanwhile, she gave birth to three healthy children from untreated pregnancies, while single pregnancy ended in miscarriage in 12 Hbd. Finally being able to undergo concluding hormonal evaluation, laboratory and radiological findings were consistent with ACTH-dependent excessive cortisol production this time. Pituitary MRI showed a lesion of <3 mm on the left side of adenohypophysis (suggesting microadenoma) and bilateral inferior petrosal sinus sampling (BIPSS) confirmed this suspicion. The patient underwent effective transsphenoid resection of the tumor and is now eucortisolaemic after one year since the operation. The genetic testing for PRKAR1A mutations was negative and the second histopathological evaluation raised considerable doubts whether the diagnosis of PPNAD was stated correctly.

Conclusions: This case illustrates that careful evaluation of hypercortisolic patients is always crucial before moving on to definite treatment. BIPSS is the procedure of significant value in patients with misleading hormonal tests’ results and uncertain source of cortisol. Isolated, non-familiar PPNAD has been very rarely reported. Pituitary lesion as the component of Carney’s complex may comprise hormonally active GH/prolactin adenoma or inactive incidentaloma, although single cases of corticotropinoma have also been described. However, genetic testing is helpful to state the diagnosis in many cases.