A Case Report Of Ectopic CRH Syndrome And Literature Review

Objective:85 to 90%cases of Cushing's syndrome are adrenocorticotropic hormone(ACTH)dependent and most of them are caused by Cushing's disease.Only 5-10%of the cases are caused by ectopic secretion of ACTH and extremely rare corticotropin-releasing hormone(CRH).The diagnose of ectopic CRH syndrome and ectopic ACTH/CRH syndrome is a challenge of clinical work with high rates of missed diagnosis and misdiagnosis.We report a case of ectopic CRH syndrome caused by a right upper arm peripheral primitive neuroectodermal tumor and collect the related detailed case reports,analyze and summarize the clinical characteristics,diagnostic methods,and diagnostic pitfalls of the disease,to improve the understanding of the disease.Methods:Report a case of ectopic CRH syndrome caused by a right upper arm peripheral primitive neuroectodermal tumor.10 cases of ectopic CRH syndrome and ectopic ACTH/CRH syndrome from the database were retroactively analyzed and literature reviewed.Results:1.The patient is a young woman,with acute onset of amenorrhea and weight gain,typical Cushing appearance,rapid disease progression,elevated blood and urine cortisol levels,and elevated ACTH levels.High-dose dexamethasone suppression test(HDDST)was not inhibited,pituitary MR without obvious abnormalities,and finally diagnosed as ectopic CRH syndrome derived from peripheral primitive neuroectodermal tumors in the right upper arm by pathological biopsy and immunohistochemical staining.2.Of the 11 cases reviewed,6 were diagnosed with ectopic CRH syndrome and 5 were diagnosed with ectopic ACTH/CRH syndrome.The main symptoms of the 11 patients were hypertension,hyperglycemia,fatigue,and hypokalemia.Other typical symptoms such as moon face,sanguineous appearance,buffalo hump,and centripetal obesity were also reflected.The median morning plasma ACTH,early morning serum cortisol,and 24h urinary free cortisol of the 11 patients were higher than the normal range.6 patients underwent HDDST,3 were able to be suppressed,and 3 was unable to be suppressed;2 patients underwent CRH stimulation test,1 positive and 1 negative.8 cases had pituitary MR examination data,only 1 displayed enlarged pituitary,the other 7 were all normal.5 patients underwent bilateral sinus blood sampling,and 3 of them had Cushing's disease-like manifestations.1 patient experienced unnecessary pituitary surgery.The 11 cases were diagnosed by immunohistochemical staining of ACTH and CRH in tumor tissues.Conclusions:Ectopic CRH syndrome and ectopic ACTH/CRH syndrome are rare diseases whose diagnosis requires detailed medical history collection,dynamic assessment of clinical manifestations,laboratory and imaging studies,dynamic tests,and pathological examinations for comprehensive assessment.It is easy to be misdiagnosed as Cushing's disease,which leads to unnecessary pituitary surgery and delays the diagnosis and treatment of patients.Doctors should strengthen their knowledge of the disease and avoid missed diagnosis and misdiagnosis.