Diagnostic Value Of Standard Posture Test In Adrenal Incidentalomas

Objective:Summarize the characteristics of standard posture test in adrenal incidentalomas(AI),and discuss its diagnostic value.Methods:We retrospectively reviewed 526 cases diagnosed with AI from 1 January 2013 to 1 January 2015 at the Endocrinology Department of Chinese PLA General Hospital,and data were colleted including baseline data,biochemical indices,functional diagnosis,postoperative pathological and immunohistochemistry.We further analyzed those AI patients wiht surgical treatment,including 204 case.And draw ROC(receiver operating characteristic) curve to evaluate the diagnostic value of standard posture test in AIs.Results:1.Of the 526 cases,259(49.2%) were male,and 267(50.8%) were female,with average age of (50.65±11.30) years.Most of them were non-functional adrenal incid-entalomas,387 cases(73.60%).And among functional AIs,53cases(10.10%) were phe-ochromocytoma(PHEO),36 cases(6.80%) were subclinical Cushing syndrome(SCS), 34 cases(6.50%) were primary aldosteronism(PA),and 16 cases (3.00%) were gangli-oneuroma(GN).In PHEO group, average level of 24 hours urinary catecholamine [norepinephrine(NE) 175.70(365.84)μg/24h,epinephrine(E) 56.92(129.21)μg/24h,do-pamine(DA) 420.47(308.23)μg/24h]was higher than other groups (P<0.05);PRA in both supine and upright position[1.90(3.70)μg/L/h,8.95(6.3)μg/L/h], △ANG[60.65 (76.80)ng/L],upright ANGⅡ [121.25(99.10)ng/L],also were higher than other groups (P<0.05).Average level of 24 hours urinary free cortisol(24h-UFC) in patients with SCS was 481.85(608.10)nmol/24h, cortisol concentration average after midnight lmg dexamethasone suppression test(1mg-DST) was 202.00 (315.00) nmol/L,both significantly higher than other groups (P< 0.05);besides, △plasma aldosterone concentration(PAC) also was higher than the other groups(P<0.05).Average upright ARR(aldosterone/renin ratio) in patients with PA was 49.29 (135.77), PAC in both supine and upright position were higher than other AIs, meanwhile,PRA and ANG Ⅱ were lower than other AIs. 2.Of the 204AI patients with surgical treatment,290 cases(44.1%) were male,and 114 cases(55.9%) were female,with average age of (47.97±10.93) years.PRA in both supine and upright position[1.90(3.70)μg/L/h,8.95(6.3)μg/L/h].upright ANG II [121.25(99.10)ng/L], △ ANG Ⅱ [60.65(76.80)ng/L] in PHEO patients and PAC in both supine and upright position[533.90(183.00)pmol/L,68.00(164.60)pmol/L],ARR [129.35(126.34),59.22(150.57)]in PA patients were highest among AI patients(P< 0.05).And supine PAC[268.95(158.40)pmol/L] in SCS patientswas lowest among AI patiens(P< 0.05).AUCROC of supine PRA,upright PRA andANG Ⅱ,△ANG Ⅱ in PHEO patients were 0.747,0.744,0.748,0.737.AUCROC of △PAC in SCS patients was 0.708.AUCROC of ARR and PAC in both supine and upright postion were 0.972,0.972, 0.854,0.816. All of them with medium diagnostic value.Conclusion:PRA, ANG Ⅱ and PAC level has different characteristics in different causes AI patients; PRA in both supine and upright postion,upright ANG Ⅱ and △ ANG Ⅱ with moderate diagnostic value in PHEO; △ PAC with moderate diagnostic value in SCS;ARR in both supine and upright postion had high diagnostic value in PA, PAC also with moderate diagnostic value.