Prolactin Assay Interference by Macroprolactin.

BACKGROUND: Macroprolactinemia is a common presentation especially in gynecology and fertility clinics. However, with this clinical condition, there is a potential for misdiagnosis and unnecessary investigations/treatments due to lack of awareness of its prevalence and diagnostic approaches amongst trainees and physicians. METHODS: In this paper, we discuss the causes of hyperprolactinemia, its pathobiology, and an approach to macro-prolactinemia including relevant clinical chemistry methods and their limitations through the case of a 45-year-old female with a history of irregular menstrual cycles, who was seen in the endocrine clinic. RESULTS: Patient did not have a history of infertility, galactorrhea, visual-disturbance, or headaches. Her physical examination and routine clinical chemistry investigations were unremarkable. Her initial prolactin level was 4,836 mIU/L (109 - 557) with subsequent results demonstrating diminishing levels of prolactin a month apart (1,023 mIU/L). Polyethylene glycol (PEG) precipitation test demonstrated the presence of macroprolactin with a 3% post-PEG recovery of prolactin and 111 mIU/L post-PEG prolactin concentration. CONCLUSIONS: Patient's post-PRL results and clinical course confirmed the presence of macroprolactin to be the cause of factitious hyperprolactinemia. A sound approach to macroprolactinemia is critical in clinical and laboratory practices.

Cribriform morular variant of papillary thyroid carcinoma in a patient with an incidental neck lump: a case report and review of the literature.

The cribriform morular variant of papillary thyroid carcinoma (CMV-PTC) is a rare morphologic entity that is associated with familial adenomatous polyposis (FAP). We report a case of a young lady with an incidentally discovered right-sided neck nodule on ultrasonography with a diagnosis of CMV-PTC confirmed on thyroidectomy and review the literature associated with the clinical presentation, imaging characteristics, pathological findings and the association with FAP.

Unravelling the mystery in a case of persistent ACTH-independent Cushing's syndrome.

INTRODUCTION: We present a rare variety of adrenocorticotrophic hormone (ACTH)-independent Cushing's syndrome known as primary pigmented nodular adrenocortical disease (PPNAD). CLINICAL PICTURE: The patient initially underwent unilateral adrenalectomy for what was thought to be a left adrenal adenoma. OUTCOME: Partial resolution of symptoms and demonstrable persistent hypercortisolism after surgery prompted further evaluation with findings leading to the diagnosis of Carney complex. A review of the adrenal histology was consistent with PPNAD. CONCLUSION: This entity of PPNAD, which has rarely been reported in Asians, forms part of the Carney complex. The diagnosis may not be simple and straightforward, as illustrated in this patient.