Clinical features and autoimmune associations in patients presenting with Idiopathic Isolated ACTH deficiency

Abstract

IIAD typically presents with insidious symptoms. Euvolaemic hyponatraemia is common at diagnosis. It is associated with autoimmune diseases, particularly primary hypothyroidism. As two patients recovered ACTH secretion, and two progressed to other pituitary hormone deficits, repeat pituitary testing should be considered, to identify recovery of function, or progression to other hormone deficits.

Clinical features and aetiology of newly diagnosed adrenal insufficiency: A single-centre retrospective cross-sectional study in Japan.

“…However, abdominal pain and diarrhoeaasgastrointestinal symptoms were relatively less common inthisstudy, although other gastrointestinal symptoms were common.Thiswas also consistent with the ndings of past studies thatshowedthat abdominal pain and diarrhoea were less common inpatients withcentral AI than in those with primary AI [3,29]. Inthe presentstudy, a substantial proportion of patients with centralAI hadhypoglycaemic episodes and hyponatremia before diagnosis.Theseresults are also consistent with the results of paststudiesinvestigating the clinical features of isolated ACTHde ciency [24,30,32] or central AI [29].…”

“…Thisresult is not consistent with the results of paststudies thatreported that more than two-thirds of central AIexcludingglucocorticoid-induced AI was caused by pituitarytumours [3,7,15,17,18]. Given that these past studies [3,15,17,18]wereconducted outside Japan and idiopathic isolated ACTH de ciencymaybe more common in Japan than in other countries [24,25],our nding suggests that pituitary tumours are a relativelylesscommon cause of central AI in Japan. However, our studyhaslimitations due to the small sample size and single-centrestudydesign.…”

“…Based on past studies andreviews [26,42,43], primary AI was de ned as AI with a plasma ACTHlevelgreater than 2 times the upper limit of the referencerange.Otherwise, AI was classi ed as central AI. There is noconsensusfor the de nition of idiopathic isolated ACTH de ciency.Based onpast cases and reviews [24,32,44,45], idiopathic isolatedACTHde ciency was identi ed if the following criteria were allmet:(1) central AI was con rmed by hormone tests; (2) no signsorlaboratory ndings suggested de ciencies in otheranteriorpituitary hormones; and (3) no organic pituitary lesionwasobserved on brain imaging.…”

“…Thus, no studies havefocused on theaetiology of newly diagnosed AI includingglucocorticoid-induced AI [4]. Furthermore, given that past studiessuggested that there aresubstantial differences in the prevalencerates of Addison'sdisease [11,13,22,23] and idiopathic isolatedadrenocorticotropichormone (ACTH) de ciency [24,25] between Japanand othercountries, it is possible that the frequency of causes ofAI inJapan is different from that in other countries.…”

“…Furthermore, few studies have focused on thefeatures ofcentral AI at presentation [4,29] because most paststudiesinvestigated only clinical features of central AI due tospeci caetiologies [24,30,[32][33][34][35], such as pituitary apoplexy [34,35] oridiopathic isolated ACTH de ciency [24,30,32]. Inaddition, nostudies have been conducted to investigate the clinicalfeatures ofglucocorticoid-induced AI because nearly all studiesregardingglucocorticoid-induced AI targeted asymptomatic ratherthansymptomatic biochemical AI induced by glucocorticoiduse [21,[36][37][38][39].…”