Primary Bilateral Macronodular Adrenal Hyperlasia With ARMC5 Mutation:a Case Report And Literature Review

Objective : Investigate and learn the clinical characteristics and the diagnosis and treatment process of primary bilateral macronodular adrenal hyperplasia,in order to improve the awareness and management of this disease.Methods : Retrospectively gather the clinical data from a case of primary bilateral macronodular adrenal hyperplasia with ARMC5 mutation from the department of endocrinology in a hospital in September 2020,review the relevant literature,summarize its clinical characteristics,laboratory inspection,imaging manifestation,pathogenesis,treatment and outcome.Results:A 41-year-old female patient,whose main manifestation were giddiness and hypodynamia,with no Cusing’s appearance,was monitored a blood pressure level around130-170/85-100 mm Hg during 4 years with family history of hypertension.Her serum potassium was slightly low.After admission to our hospital,the detection of endocrine hormones showed that the concentration of ACTH was decreased while the plasma cortisol(8:00 and 16:00)and the 24-hour urine free cortisol(UFC)were normal.Then cortisol couldn’t be suppressed after both low dose and high dose dexamethasone suppression tests.MR imagine revealed the posibility of multifocal mircoadenoma in pituitary.Bilateral macronodular adrenal hyperplasia could be seen through contrast-enhanced CT scan of epigastrium and the maximum nodule size was about1.4cm in the right.Her chromosomes were 46,XX.Whole exome sequencing indicated a ARMC5 hybrid transgenation on 16 p c.C2692 T.It meant that since base C mutated to T from 2692 of ARMC5,then tryptophane substituted for arginine,named p.R898 W.Father’s ARMC5 analysis showed wild type while mother’ and sister’s are as same as her.In addition,the CT scan on upper abdominal of her sister also reported bilateral adrenal marconodular hyperplasia.This patient was diagnosed PBMAH.Subsequently laparoscopic right adrenalectomy was performed in the department of urology in our hospital.The excised adrenal gland contained several yellow nodules,not pigmented,and final pathology diagnosis was macronodular adrenal hyperplasia,which confirmed our clinical consider.During the follow-up,her symptoms reliefed,blood pressure was well controlled and serum potassium returned to normal.Conclusion:Primary bilateral macronodular adrenal hyperplasia is a kind of Cushing’syndrome with atypical clinical manifestation and biochemical examination that is rarely seen.It is helpful to confirm this disease using high dose dexamethasone suppression test and adrenal image based on the diagnose of Cushing’ syndrome through standard low dose dexamethasone suppression test.Recommending gene detection if possible.ARMC5 is the commonest type of gene mutation.It may find more family or subclinical patients if the propositus’ family members take further screen.Surgery(unilateral or bilateral excision)is a main kind of therapy.