原发性醛固酮增多症患者血清NT-proBNP改变及临床意义研究

目的探讨原发性醛固酮增多症(PA)患者血清脑利钠肽前体N末端(NT-proBNP)改变及临床意义。方法纳入2012年1月至2015年12月疑似PA的高血压患者140例,分为PA组(n=30)和原发性高血压(EH)组(n=110)。检测两组患者血清NT-proBNP和肾素水平,并通过受试者工作特征曲线(ROC曲线)分析以及相关性分析比较血清NT-proBNP水平与PA的相关性。结果 PA组患者血清NT-proBNP水平[(93.9±7.3)pg/mL]明显高于EH组患者[(69.5±10.4)pg/mL],差异有统计学意义(P0.05)。单侧亚组PA患者肾素[(6.8±1.3)pg/mL vs.(5.1±0.6)pg/mL]、血浆醛固酮/血浆肾素比值(ARR)[(65.5±16.4)vs.(57.1±14.4)]和NT-proBNP[(101.9±14.1)pg/mL vs.(90.4±8.1)pg/mL]水平明显高于双侧亚组,差异均有统计学意义(P0.05)。NT-proBNP预测PA的AUC为0.809,95%CI:0.734~0.865,cut-off为98.4pg/mL,敏感度为83.4%,特异度为78.6%。预测单侧PA的AUC为0.733,95%CI:0.648~0.804,cut-off为109.6pg/mL,敏感度为79.9%,特异度为81.5%。血清NT-proBNP水平与ARR(r=0.765,P0.05)、PA(r=0.728,P0.05)和单侧PA(r=0.778,P0.05)呈正相关。结论 PA患者相比EH患者血清NT-proBNP水平轻度升高,有助于PA患者的早期诊断和筛查。     

99Tcm-MDP SPECT/CT诊断宫颈癌放疗后骨盆不全骨折

目的 探讨⁹⁹Tc^m-MDP SPECT/CT诊断宫颈癌放疗后骨盆不全骨折（PIF）的价值。方法 回顾性分析37例宫颈癌放疗后疑似PIF患者的全身显像（WBS）和骨盆SPECT/CT断层融合显像资料。以影像学资料、临床资料及随访（>12个月）结果作为最终诊断PIF的标准,比较WBS、SPECT/CT对PIF的诊断效能。结果 37例患者共50个骨盆病灶,最终诊断PIF 42个（30例）。WBS诊断PIF的灵敏度为45.24%（19/42）,特异度50.00%（4/8）,准确率46.00%（23/50）;SPECT/CT诊断PIF的灵敏度为92.86%（39/42）,特异度75.00%（6/8）,准确率90.00%（45/50）;SPECT/CT诊断宫颈癌放疗后PIF的灵敏度及准确率均高于WBS（χ²=22.28、22.24,P均<0.01）,但二者特异度差异无统计学意义（P=0.31）。结论 ⁹⁹Tc^m-MDP SPECT/CT可用于诊断宫颈癌放疗后PIF。     

18F-FDG PET/CT诊断非小细胞肺癌纵隔淋巴结转移

目的 探讨¹⁸F-FDG PET/CT诊断非小细胞肺癌（NSCLC）纵隔淋巴结转移的价值。方法 回顾性分析130例初诊NSCLC患者（337个纵隔淋巴结）术前PET/CT资料,与术后病理结果相对照,评价PET/CT诊断NSCLC纵隔淋巴结转移的灵敏度、特异度及准确率。结果 以患者为观察单位,PET/CT发现纵隔淋巴结转移66例,无纵隔淋巴结转移64例,灵敏度79.41%（54/68）,特异度80.65%（50/62）,准确率80.00%（104/130）,阳性预测值81.82%（54/66）,阴性预测值78.13%（50/64）;以淋巴结数为单位,PET/CT诊断纵隔淋巴结转移125个,非纵隔淋巴结212个,PET/CT诊断纵隔淋巴结转移的灵敏度74.42%（96/129）,特异度86.06%（179/208）,准确率81.60%（275/337）,阳性预测值76.80%（96/125）,阴性预测值84.43%（179/212）。PET/CT结果与病理结果比较差异无统计学意义。结论 ¹⁸F-FDG PET/CT诊断NSCLC纵隔淋巴结转移具有较高价值。     

去甲乌药碱负荷心肌灌注显像评价冠心病心肌血供

目的 评价盐酸去甲乌药碱（HG）负荷核素心肌灌注显像（MPI）对冠心病（CHD）的诊断价值。方法 对65例入选患者采用交叉试验法分别先后给予HG注射液（HG组）和安慰剂注射液（安慰剂组）的负荷试验,行负荷-静息^99mTc-MIBI MPI检查,以CAG结果为金标准,计算HG负荷显像诊断CHD的灵敏度、特异度、准确率、阳性预测值和阴性预测值。结果 HG注射液心脏负荷试验MPI诊断CHD的灵敏度为69.57%（16/23）、特异度为97.62%（41/42）、准确率为87.69%（57/65）、阳性预测值为94.12%（16/17）、阴性预测值为85.42%（41/48）。在HG负荷试验中,63例患者出现不同程度的不良反应,表现为心悸（57例）、胸闷（17例）、头晕（1例）、胸痛（10例）等,症状较轻微,停药后10 min内自行缓解。结论 HG作为心脏负荷试验药物用于MPI诊断CHD,具有较好的诊断效能,其不良反应轻微,安全可行,有望成为一种新型的心脏负荷试验药物。     

超声“萤火虫”成像鉴别诊断乳腺占位病变

目的 探讨超声"萤火虫"成像（MI）对鉴别诊断乳腺良恶性病变的临床应用价值。方法 对134例乳腺占位病变患者行MI和常规乳腺X线摄影（MMG）检查，观察微钙化分布及形态，通过活检或术后病理检查明确诊断。采用ROC曲线评价MI、MMG对乳腺恶性病变的诊断效能。结果 病理诊断乳腺良性病变85例、恶性49例，MI正确诊断良性82例、恶性44例，MMG正确诊断良性69例、恶性34例。簇状和线性分布的微钙化更倾向于恶性病变。ROC曲线结果显示，以MMG所示每平方厘米病灶内存在5个钙化点为截断值，诊断恶性病变的AUC为0.64（P=0.01），敏感度69.39%（34/49），特异度81.18%（69/85），准确率76.87%（103/134）；以MI所示每平方厘米病灶内存在3个强回声点为截断值，诊断乳腺恶性病变的AUC为0.76（P<0.01），敏感度89.80%（44/49），特异度96.47%（82/85），准确率94.03%（126/134）。结论 MI所示微钙化数量及分布有助于鉴别诊断乳腺良恶性病变，且诊断效能高于MMG。     

二维超声联合声触诊组织成像定量技术诊断唾液腺干燥综合征

目的 观察二维超声联合声触诊组织成像定量（VTIQ）技术诊断唾液腺干燥综合征（SS）的价值。方法 收集43例SS患者（SS组）和60例非SS患者（对照组）,观察并对比其唾液腺病灶二维超声评分及剪切波速度（SWV）,绘制受试者工作特征（ROC）曲线,评估二维超声评分、VTIQ及二者联合诊断唾液腺SS的效能。结果 SS组唾液腺二维超声评分及唾液腺SWV均明显高于对照组（P均<0.01）。以2.12、2.38 m/s为唾液腺（腮腺、下颌下腺）SWV最佳截断值,其诊断唾液腺SS的敏感度、特异度、约登指数和曲线下面积（AUC）分别为83.70%、88.30%、0.72和0.90;以二维超声评分2分为最佳截断值,其诊断唾液腺SS的敏感度、特异度、约登指数和AUC分别为76.70%、90.00%、0.67和0.91;以二维超声评分为1分且唾液腺SWV=2.12、2.38 m/s为最佳截断值,联合诊断唾液腺SS的敏感度、特异度、约登指数和AUC分别为95.30%、60.00%、0.55和0.78。结论 二维超声联合VTIQ技术有助于诊断唾液腺SS。     

血浆ARR筛查原发性醛固酮增多症的应用分析

目的探讨血浆醛固酮/肾素活性比值(ARR)在原发性醛固酮增多症(PA)的应用分析。方法选取2016年1月至2017年12月在驻马店市中心医院治疗的PA患者78例(PA组),同时选取疑似PA但确诊为原发性高血压(EH)患者120例(EH组),比较两组临床一般资料以及卧位、立位ARR水平。方法 PA组收缩压、舒张压和尿钾分别为(162.20±20.03)mmHg、(103.20±12.23)mmHg和(37.18±9.39)mmol/L,明显高于EH组(P0.05),而血钾为(3.02±0.55)mmol/L,明显低于EH组(P0.05);PA组卧位、立位ARR分别为73.01(42.23,120.03)ng·dl-1/ng·ml-1·h-1和60.10(30.12,220.43)ng·dl-1/ng·ml-1·h-1,明显高于EH组(P0.05);卧位ARR和立位ARR诊断PA的ROC曲线下面积分别为0.910和0.946(P0.05),卧位ARR和立位ARR截断值分别为15.96ng·dl-1/ng·ml-1·h-1和32.96ng·dl-1/ng·ml-1·h-1,灵敏度分别为94.90%和100.00%,特异度分别为80.83%和81.67%。结论血浆ARR筛查PA有重要作用,其中立位ARR筛查诊断的价值可能较高,值得进一步研究。     

血浆醛固酮/肾素活性比值与血清钾在原发性醛固酮增多症诊断中的临床意义

目的探讨血浆卧位ARR比值与血清钾浓度在原发性醛固酮增多症(PA)疾病中的临床诊断价值。方法以PA患者66例作为疾病组,非PA高血压患者58例为对照组,采用放射免疫法测定血醛固酮(SAC)及肾素活性(PRA),采用离子选择电极法测定血清钾,并计算ARR比值(SAC/PRA)。结果 PA组中ARR比值和血清钾浓度分别为203.47±50.23和2.76±0.72mmol/L,与对照组间的差异均达到显著水平(P0.01)。以卧位ARR比值为112.0作为临界值,诊断PA的灵敏度为92.42%,特异性为87.93%,诊断符合率为90.32%;卧位ARR比值与血清钾浓度联合进行诊断时,灵敏度为98.48%,特异性为86.20%,诊断符合率为92.74%。结论血浆卧位ARR比值与血清钾浓度联合测定可用于PA疾病的临床诊断,但将卧位ARR比值与血清钾浓度指标联合检测时具有更高的诊断符合率,可提高PA的检出率。     

剪切波弹性成像与18F-FDG PET/CT显像诊断甲状腺微小癌的对比

目的 比较剪切波弹性成像与¹⁸F-FDGPET/CT显像诊断甲状腺微小癌的价值。方法 回顾性分析经病理证实的甲状腺小结节患者超声剪切波弹性成像及¹⁸F-FDGPET/CT显像资料,计算并比较2种方法诊断甲状腺微小癌的灵敏度、特异度、准确率、阳性预测值及阴性预测值。结果 48个甲状腺小结节中,37个为恶性结节,11个为良性结节,剪切波弹性成像与¹⁸F-FDGPET/CT显像诊断甲状腺微小癌的灵敏度、特异度、准确率、阳性预测值及阴性预测值结果分别为91.89%（34/37）、81.82%（9/11）、89.58%（43/48）、94.44%（34/36）、75.00%（9/12）和29.73%（11/37）、72.73%（8/11）、39.58%（19/48）、78.57%（11/14）、23.53%（8/34）;两种方法的灵敏度、准确率及阴性预测值差异有统计学意义（P均<0.05）,特异度、阳性预测值差异无统计学意义（P均>0.05）。结论 剪切波弹性成像对甲状腺微小癌的诊断价值优于¹⁸F-FDGPET/CT。     

实时剪切波弹性成像应用于股总静脉血栓临床分期

目的 探讨实时剪切波弹性成像（SWE）应用于股总静脉血栓（CFVT）临床分期的价值。方法 根据主诉发病时间将92例单侧CFVT患者分为急性期（1~14天,n=41）、亚急性期（15~30天,n=24）及慢性期（>30天,n=27）,比较其二维超声评分及SWE所测杨氏模量值。采用ROC曲线评价二维超声及SWE对急性期、慢性期CFVT的诊断效能。结果 3期患者间二维超声评分及杨氏模量值总体比较（P均<0.001）及两两比较差异均有统计学意义（P均<0.05）。以杨氏模量值=13.50 kPa为截断值,SWE诊断急性期CFVT的AUC为0.916（P<0.05）,敏感度85.37%,特异度82.35%;以二维超声评分=2.00为截断值,二维超声诊断急性期CFVT的AUC为0.800（P<0.05）,敏感度75.61%,特异度66.67%;2种方法AUC差异有统计学意义（P<0.001）。以杨氏模量值=16.40 kPa为截断值,SWE诊断慢性期CFVT的AUC为0.917（P<0.05）,敏感度85.19%,特异度87.69%;以二维超声评分=2.03为截断值,二维超声诊断慢性期CFVT的AUC为0.842（P<0.05）,敏感度87.21%,特异度69.23%;两种方法AUC差异有统计学意义（P=0.010）。结论 SWE可用于判断CFVT临床分期,且效果好于常规超声。     

Analytical validation and investigation on reference intervals of aldosterone and renin in Chinese Han population by using fully automated chemiluminescence immunoassays

BackgroundThe aldosterone/renin ratio (ARR) is recommended to screen for primary aldosteronism (PA) in hypertension. We estimated fully automated chemiluminescence immunoassays (CLIA) for plasma aldosterone concentrations (PAC) and plasma direct renin concentrations (PRC) and investigated their reference intervals in Chinese Han population.MethodsPAC and PRC were measured on a fully automated analyzer (LIAISON XL, DiaSorin, Italy). Performance characteristics were estimated according to CLSI approved guidelines. 328 healthy individuals were selected for reference intervals investigation. Results simultaneously tested by CLIA and radioimmunoassays were reviewed from 123 patients with hypertension and/or adrenal space-occupying lesion. PAC/PRC ratio (ARR_prc) was compared to PAC/plasma renin activity (PRA) ratio (ARR_pra).ResultsWithin-laboratory imprecision was 5.6%–6.7% for PAC and 3.0%–3.3% for PRC. The LoQ was 72.2 pmol/L for PAC and 1.27 mIU/L for PRC. Linearity was excellent in the range of concentrations between 94 and 2708 pmol/L for PAC and 1.3–461.8 mIU/L for PRC. Interferences of hemoglobin, unconjugated bilirubin and lipaemia could be acceptable, but not of conjugated-bilirubin when renin and aldosterone at low concentrations. The central 95% reference intervals for males: PAC: 76–722 pmol/L, PRC: 3.3–92.7 mIU/L, ARR: 2.2–46.0 pmol/mIU; for females: PAC: 85–1010 pmol/L, PRC: 3.7–99.8 mIU/L, ARR: 3.6–68.4 pmol/mIU. Upper reference limits for ARR of younger and older men were lower than women. ARR_prc and ARR_pra showed almost perfect agreement (kappa = 0.815) for screening PA.ConclusionThe DiaSorin tests are valuable analytical options for PAC and PRC measurements. We recommend sex-specific and age-specific reference intervals of these items should be estimated.     

Diagnosis of primary aldosteronism: Comparison of post-captopril active renin concentration and plasma renin activity

BackgroundA common pharmacologic test for the diagnosis of primary aldosteronism (PA) is the administration of captopril to determine whether an abnormal plasma aldosterone concentration (PAC) to plasma renin activity (PRA) ratio(ARR) persists, although active renin concentration (ARC) may offer advantages with regard to processing and standardization.MethodsA prospective, head-to-head study was conducted between Feb 2008 and Dec 2008. One hundred and fourteen patients enrolled and received captopril to aid in the diagnosis of PA in the TAIPAI intervention.ResultsFifty-one patients were diagnosed with PA. Post-captopril ARC was significantly correlated with PRA. The area under the receiver operating characteristic curve of the post-captopril ARR was not different in PRA vs ARC measurements. When post-captopril ARC-based ARR (ARR_ARC) > 35.5 as the cut-off value, we obtained sensitivity of 75.0% and specificity of 86.4% to differentiate PA from essential hypertension.ConclusionsThe correlation of individual PRA and ARC after administration of captopril was excellent; especially at the lower PRA levels. Post-captopril ARR_ARC values used to diagnose PA are not different from post-captopril PRA-based (ARR_PRA) values in patients without kidney, liver and heart failures. Primary aldosteronism can be diagnosed with a post-captopril cut-off value of ARR_ARC > 35.5 pmol/ng.     

经手术病理证实的原发性醛固酮增多症102例临床分析

目的在经手术病理证实的原发性醛固酮增多症(PA)患者中评价术前各项诊断筛查方法的临床价值。方法回顾性分析经手术病理证实的102例PA患者的临床特征、生化资料及血浆醛固酮浓度(PAC)、血浆醛固酮与肾素比值(ARR),比较不同指标筛查PA的阳性率,不同试验对PA的确诊率及影像学检查对PA的检出率和诊断符合率。结果在上述患者中:(1)ARR>20 ng/dl·(ng·ml-1·h-1)-1筛查PA的阳性率为86.27%;ARR>20 ng/dl·(ng·ml-1·h-1)-1且PAC>15 ng/dl筛查PA的阳性率为68.63%(P<0.01)。(2)静脉盐水抑制试验和卡托普利抑制试验对PA的确诊率分别为100%和80%(P>0.05)。(3)影像学检查中,CT和MRI对PA的检出率明显高于超声(P<0.01);与术后病理对照,CT对醛固酮腺瘤(APA)和单侧肾上腺皮质增生(UAH)的诊断符合率分别为97.33%和78.26%(P<0.01),MRI对APA和UAH诊断符合率分别为88.89%和75.00%(P>0.05)。结论 ARR>20 ng/dl·(ng·ml-1·h-1)-1筛查PA的阳性率高于ARR>20 ng/dl·(ng·ml-1·h-1)-1联合PAC>15 ng/dl;盐水抑制试验和卡托普利抑制试验都有较高的确诊率;影像学检查中,CT对PA有较高的检出率和诊断符合率,对于分型而言,CT对APA的诊断符合率高于UAH。     

醛固酮与肾素活性比值对原发性醛固酮增多症的诊断价值

目的 评价醛固酮与肾素活性比值(ALD/PRA,ARR)对原发性醛固酮增多症(PA)的诊断价值.方法 回顾性收集44例PA、9例嗜铬细胞瘤、8例无功能性瘤、12例库欣综合征、4例肾动脉狭窄及13例原发性高血压患者的ALD、PRA结果,计算ARR,采用受试者操作特性(ROC)曲线评价各项指标的诊断价值.结果 卧位ALD ROC曲线下面积为0.947,临界值(cut-off值)为174.1 ng/L时,敏感度为86.4%,特异度为91.3%.立位ALDROC曲线下面积为0.889,cut-off值为209.8 ng/L时,敏感度为84.1%,特异度为87.0%.卧位ARR ROC曲线下面积为0.978,cut-off值为40.8 ng·dl-1/ng·ml-1·h-1时,敏感度为95.5%,特异度为95.7%;立位ARR ROC曲线下面积为0.981,cut-off值为35.26 ng·dl-1/ng·ml-1·h-1时,敏感度为95.5%,特异度为93.5%;联合立位ARR和立位ALD,其诊断价值明显优于单一指标,当立位ALD>275 ng/L,立位ARR ROC曲线下面积为0.989,cut-off值为23.73 ng·dl-1/ng·ml-1·h-1时,特异度为100%,敏感度为95.7%.结论 ARR诊断PA的价值高于ALD、PRA,立位ARR优于卧位,当联合立位AID>275ng/L,则诊断价值更大.     

醛固酮肾素定量比值筛查原发性醛固酮增多症的探讨

目的探讨醛固酮肾素定量比值(PAC/PRC以下简称AARR)筛查原发性醛固酮增多症(以下简称为原醛症)的价值。方法使用化学发光方法检测32例原醛症和88例原发性高血压患者立、卧位醛固酮和肾素浓度,计算醛固酮肾素浓度比值(AARR),构建AARR对原醛症的ROC曲线,确定AARR筛查原醛症的最佳切点。结果原醛症患者组立位肾素浓度为4.55(15.67)pg/ml,卧位为2.85(5.34)pg/ml,立位醛固酮浓度为213.70(237.38)pg/ml,卧位为207.52(137.90)pg/ml, 立位AARR为61.53(182.84),卧位为100.69(254.03)。原发性高血压患者组立位肾素浓度为6.80(11.90)pg/ml,卧位为4.79(8.36)pg/ml,立位醛固酮浓度为121.20(31.94)pg/ml,卧位为112.47(23.99)pg/ml,立位AARR为17.49(28.57),卧位为22.67(37.43)。立位AARR筛查原醛症的ROC曲线AUC为0.802,Youden’s指数提示最佳切点为54.40 pg/ml,灵敏度为0.719,特异度为0.852;卧位AARR筛查原醛症的ROC曲线AUC为0.848,最佳切点为64.18 pg/ml,灵敏度为0.750,特异度为0.818。卡方检验提示立、卧位AARR筛查原醛症的诊断效果差异无统计学意义(P>0.05)。结论临床上采用醛固酮肾素定量比值对原发性醛固酮增多症进行筛查有一定的应用价值,且立、卧位AARR诊断效果相当。     

Re‐evaluation of the fludrocortisone test: duration,NaCl supplementation and cut‐off limits for aldosterone

Objective. Primary aldosteronism (PA) is the most common form of secondary hypertension. Thus, the aims of this study were: (1) to clarify whether the fludrocortisone suppression test (FST), which confirms autonomous aldosterone secretion, is reliable when carried out during a shorter period of time and (2) to confirm the importance of NaCl supplementation. The cut‐off limits already obtained for aldosterone in healthy subjects during the FST were applied in hypertensive patients with a high aldosterone to renin ratio (ARR). Material and methods. The healthy subjects were allocated to three groups. Fludrocortisone was administered 4 times daily over 4 days and sodium chloride was supplemented in 3 different doses. The result was applied in 24 hypertensive patients, in 24 healthy subjects (10 women (23–38 years old) and 14 men (23–58 years old)) and in 24 patients with hypertension and high ARR (16 women (45–74 years old) and 8 men (56–73 years old)). Blood pressure, aldosterone, renin, potassium and sodium were measured. Results. After three days of FST, there was a significant decrease in the serum level of aldosterone in the healthy subjects, regardless of high or low sodium chloride supplementation (p<0.001). The decrease in serum aldosterone was significantly less pronounced in patients with PA than in healthy subjects and hypertensive patients without PA (p<0.001). The 95th percentile of plasma aldosterone at the end of the test was 225?pmol/L. Conclusions. The FST can be shortened to 3 days and a daily 500?mg NaCl supplementation is sufficient. A cut‐off value for aldosterone of 225?pmol/L after 4 days with FST is appropriate.     

High frequency of primary hyperaldosteronism among hypertensive patients from a primary care area in Sweden

OBJECTIVE: To search for primary hyperaldosteronism (PHA) among previously known hypertensive patients in primary care, using the aldosterone/renin ratio (ARR), and to evaluate clinical and biochemical characteristics in patients with high or normal ratio. DESIGN: Patient survey study. SETTING AND SUBJECTS: The study population was recruited by written invitation among hypertensive patients in two primary care areas in Sweden. A total of 200 patients met the criteria and were included in the study. MAIN OUTCOME MEASURES: The ARR was calculated from serum aldosterone and plasma renin concentrations. The cut-off level for ARR was set to 100, as confirmed in 28 healthy subjects. Patients with increased ARR were considered for a confirmatory test, using the fludrocortisone suppression test. RESULTS: Of 200 patients, 50 patients had ARR > 100; 26 patients were further evaluated by fludrocortisone suppression test. Seventeen of these patients had an incomplete aldosterone inhibition. CONCLUSION: In total 17 of 200 evaluated patients (8.5%) had an incomplete suppression with fludrocortisone. This confirms previous reports on a high frequency of PHA. No significant biochemical or clinical differences were found among hypertensive patients with PHA compared with the whole sample.     

Primary aldosteronism among newly diagnosed and untreated hypertensive patients in a Swedish primary care area

Objective

To evaluate the prevalence of primary aldosteronism (PA) in newly diagnosed and untreated hypertensive patients in primary care using the aldosterone/renin ratio (ARR), and to assess clinical and biochemical characteristics in patients with high and normal ARR.

Design

Patient survey study.

Setting and subjects

A total of 200 consecutive patients with newly diagnosed and untreated hypertension from six primary health care centres in Sweden were included.

Main outcome measures

ARR was calculated from serum aldosterone and plasma renin concentrations. The cut-off level for ARR was 65. Patients with an increased ARR were considered for confirmatory testing with the fludrocortisone suppression test (FST), followed by adrenal computed tomographic radiology (CT) and adrenal venous sampling (AVS).

Results

Of 200 patients, 36 patients had an ARR > 65. Of these 36 patients, 11 patients had an incomplete aldosterone inhibition during FST. Three patients were diagnosed with an aldosterone producing adenoma (APA) and eight with bilateral adrenal hyperplasia (BHA). Except for moderately lower level of P-K in patients with an ARR > 65 and in patients with PA, there were no biochemical or clinical differences found among hypertensive patients with PA compared with patients without PA.

Conclusion

Eleven of 200 evaluated patients (5.5%) were considered to have PA. The diagnosis of PA should therefore be considered in newly diagnosed hypertensive subjects and screening for the diagnosis is warranted.Key Words: Aldosterone, aldosterone to renin ratio, family practice, hypertension, primary aldosteronism, reninPrimary aldosteronism (PA) is common in patients diagnosed with “essential hypertension” in specialized centres; however, reports on prevalence in primary care are few.

• Screening with the aldosterone to renin ratio followed by confirmatory testing showed that 5.5% of newly diagnosed and untreated hypertensive patients had PA.
• No particular clinical features could distinguish these patients from patients with essential hypertension.
• Screening for PA should always be performed in younger patients with newly diagnosed hypertension and in patients with resistant hypertension irrespective of potassium concentrations.

Hypertension affects up to 25% of the adult population in Sweden [1,2]. Primary aldosteronism (PA) is a common form of secondary hypertension, characterized by excessive aldosterone secretion and renin suppression, followed by hypertension, alkalosis and hypokalemia [3–6]. The latter is, however, not necessarily an integral element [3–6]. Resistant hypertension requiring more than three antihypertensive drugs, hypertension diagnosed at a young age, or family history of stroke at a young age are factors that suggest the possibility of PA [7]. PA arises from one or both adrenal glands. The two major subtypes are aldosterone producing adenoma (APA; 1/3 of the cases) and bilateral adrenal hyperplasia (BAH; 2/3 of the cases). APA is preferably treated by surgery while BHA is treated with aldosterone antagonists. The diagnosis thus enables tailored medical therapy or surgical intervention with possible cure [8].PA has been considered a rare cause of hypertension [9] but recent studies suggest a prevalence of 5–10% [3,4,10–17]. Frequencies vary in different study populations and are increased in severe hypertension, especially at referral centres treating resistant hypertension [12]. Despite the fact that a number of studies have been carried out, the prevalence among primary care patients still remains uncertain. In a previous study [13] we confirmed an 8.5% prevalence of PA among 200 screened hypertensive patients in primary care. However, these patients had all been treated with antihypertensive medication for several years, which might have affected the attendance for screening, since only approximately 50% of invited subjects participated. Furthermore, it is known that a number of antihypertensive drugs alter the aldosterone to renin ratio (ARR); therefore withdrawal of medication is strongly suggested before screening [18].The aim of this study was to clarify the prevalence of PA by screening newly diagnosed and medically untreated hypertensive patients in primary care. Patients with a high ARR were referred for confirmatory testing. In addition, the study compared clinical and biochemical characteristics in patients with high or normal ARR.     

The aldosterone to renin ratio in the diagnosis of primary aldosteronism: Promises and challenges

The complexity of evaluating patients for secondary treatable causes of hypertension is underappreciated. Primary aldosteronism (PA) is the most prevalent cause of secondary hypertension (3%‐32% of hypertensive patients). The recent endocrine society clinical practice guideline (ESCPG), “The Management of Primary Aldosteronism: Case Detection, Diagnosis, and Treatment”, differs from the previous version in the explicit recognition of PA as a major public health issue. Despite this, PA is underdiagnosed. The guidelines call on physicians to substantially ramp up the screening of hypertensive patients at risk of PA. Further, it recommends the plasma aldosterone to renin ratio (ARR), as the test of choice for screening for PA. However, the ARR is a highly variable test with reported diagnostic sensitivities and specificities ranging from 66% to 100% and 61% to 100%, respectively. Variability of the ARR can be attributed to the high degree of within‐subject variation, differences in sampling protocols, laboratory assays, reporting units, the effect of medications and the population characteristics used to establish the decision thresholds. These factors render the possibility of false positive and false negative results—which have the potential to adversely impact patients. The limitations and caveats to the use of the ARR necessitate an effective clinic‐laboratory interface, with specialist physician and clinical scientist collaboration for ARR result interpretation. Improvement in the diagnostic sensitivity and specificity of the ARR is predicated on harmonisation of pretesting patient preparation criteria, knowledge of the analytical methods used to derive the ratio and the method‐specific threshold for PA.