Conn's syndrome and bilateral renal artery stenosis in the presence of multiple renal arteries

Concurrent Primary Aldosteronism and Renal Artery Stenosis: An Overlooked Condition Inducing Resistant Hypertension

To explore the clinical features of coexisting primary aldosteronism (PA) and renal artery stenosis (RAS), we retrospectively analyzed records from 71 patients with PA with RAS and a control group of 121 patients with PA without RAS. Aldosterone-to-renin concentration ratio tests and computerized tomography (CT) scanning of the adrenal and renal arteries were routinely conducted to screen for PA and RAS. Color Doppler flow and/or magnetic resonance imaging were used as substitute testing of patients for whom CT was contraindicated. Standard percutaneous renal arteriography (PTRA) was considered for patients with RAS exceeding 70% based on non-invasive tests and for those without PTRA contraindications. The patients with PA with RAS were further divided into severe (RAS>70%) and moderate (50% < RAS <70%) RAS groups. The prevalence of RAS among PA patients was 6.9% (71/1,033), including 3.2% (33/1,033) with severe RAS. Compared with the PA without RAS group, the severe RAS group showed higher levels of systolic blood pressure (SBP) (171.82 ± 18.24 vs. 154.11 ± 18.96 mmHg; P < 0.001) and diastolic BP(DBP) (110.76 ± 15.90 vs. 91.73 ± 12.85 mmHg; P < 0.001) and prevalence of resistant hypertension (RH) (90.9 vs. 66.9%; P = 0.008), whereas the moderate RAS group merely showed higher DBP (98.63 ± 14.90 vs. 91.73 ± 12.85 mmHg; P = 0.006). The direct renin concentrations (DRCs) (5.37 ± 3.94 vs. 3.71 ± 2.10 μU/mL; P < 0.001) and false-negative rate (33.8 vs. 3.3%; P < 0.01) of PA screening tests were significantly higher in the PA with RAS group than in the control group, but only in severe RAS group, in subgroup analysis. Among patients who underwent successful treatment for severe RAS, mean DRC decreased from 11.22 ± 9.10 to 3.24 ± 2.69 μIU/mL (P < 0.001). Overall, the prevalence of RH decreased from 81.7 to 2.8% (P < 0.001) when both PA and RAS were treated with standard methods. PA with concurrent severe RAS is a condition that induces RH. PA can be easily missed in patients with coexisting RAS. RAS patients with RH after successful revascularization for RAS should be evaluated for coexisting PA.

[Association of renovascular hypertension and primary aldosteronism]

INTRODUCTION

Renal artery stenosis is rarely associated with Conn adenoma.

CASE REPORT

We report a 27-year-old male patient who presented in 2001 with a severe high blood pressure associated with hypokaliemia. Radiologic investigations showed a left renal artery stenosis with agenesis of left kidney. A left nephrectomy was performed and blood pressure returned to normal with a single antihypertensive drug. Five years later, the patient again presented with severe high blood pressure. Laboratory studies revealed a low serum potassium level at 2.8 mmol/L associated with high urinary potassium excretion (84 mmol/24h) and a very high aldosterone/renin ratio (>462). Abdominal CT scan demonstrated a right adrenal mass. The patient underwent a right adrenalectomy (adenoma). Blood pressure returned to normal with a single antihypertensive. Serum potassium levels as well as aldosterone/renin ratio normalized.

CONCLUSION

We discussed whether the association between these two entities is merely fortuitous or conversely based on a causal relationship.

[A 58-year-old hypertensive patient with primary hyperaldosteronism and renal artery stenosis]

BACKGROUND

Secondary hypertension can rarely be caused by different disorders as shown in the present case with simultaneous occurrence of two possible causes.

CASE REPORT

Magnetic resonance imaging findings of a 58-year-old patient showed an eccentric left renal artery stenosis of 60-70% and an inhomogeneous tumor of the left adrenal gland. After percutaneous transluminal angioplasty, elevated plasma aldosterone concentrations persisted. Adrenal vein sampling in the authors' hospital confirmed a primary hyperaldosteronism due to unilateral adenoma. Subsequently, unilateral laparoscopic adrenalectomy was performed.

CONCLUSION

Atherosclerotic renal artery stenosis stimulates the renin-angiotensin system and thereby causes secondary hypertension. Furthermore, adrenal disorders that lead to abnormal aldosterone secretion, i.e., primary hyperaldosteronism, often result in secondary hypertension. Though the simultaneous occurrence of two potential causes of secondary hypertension is rare, it has to be considered for differential diagnosis and therapy. The presumed pathophysiological relevance should guide the order of therapeutic measures.

A case of primary aldosteronism associated with renal artery stenosis and preclinical Cushing's syndrome

We identified a left adrenal tumor, left renal atrophy, and left renal artery stenosis (RAS) in a 52-year-old man by MRI/magnetic resonance angiography (MRA) during evaluation of hypertension. Laboratory tests revealed hypokalemia, a high plasma aldosterone concentration (PAC), low plasma renin activity (PRA), and normal plasma cortisol. An excessive response of aldosterone and cortisol to adorenocorticotrophic hormone (ACTH) was found upon selective sampling of the left adrenal vein. Selective renal venous sampling showed a left/right renal venous PRA ratio of 1.7. A dexamethasone (8 mg) suppression test showed insufficient suppression of cortisol. We diagnosed this patient as having aldosterone-producing adrenal adenoma (APA) associated with renovascular hypertension (RVH) and preclinical Cushing's syndrome. As an initial treatment, percutaneous transluminal renal angioplasty was performed. Postoperatively, the patient's blood pressure decreased. One month later, the tumor was removed by complete laparoscopic left adrenalectomy. Postoperatively, blood pressure decreased further and both PAC and PRA were normalized. However, antihypertensive therapy could not be completely stopped. The renal dysfuntion that occurred prior to treatment seemed to prevent complete normalization of blood pressure.

Primary hyperaldosteronism: a frequent cause of residual hypertension after successful endovascular treatment of renal artery disease

BACKGROUND

Poor blood pressure control in renal artery disease patients after percutaneous renal angioplasty (PTRA), with or without stenting (PTRAS), may be due to pre-existing hypertension. Primary hyperaldosteronism is much more frequent than was previously suspected. We hypothesized that residual hypertension observed in some renal artery disease patients after technically successful endovascular treatment may be due to primary hyperaldosteronism.

METHODS

Only patients free of significant residual artery stenosis were included in the study. Aldosterone and renin were measured in 52 renal artery disease patients (8 with fibrodysplastic and 44 with atherosclerotic lesions), in whom successful PTRA/PTRAS had been performed previously. An aldosterone-to-renin ratio > or = 23 pg/ml per pg/ml was considered as the cut-off value for performing tests to confirm the diagnosis of primary hyperaldosteronism.

RESULTS

Residual hypertension (blood pressure > or = 160/90 mmHg) was observed in 24/52 patients (46%) after revascularization. A raised aldosterone-to-renin ratio was found in nine subjects (17.3%), eight of whom had poor blood pressure control (33% of patients with residual hypertension). A diagnosis of primary hyperaldosteronism was confirmed in seven patients (four atherosclerotic, three fibrodysplastic). All fibrodysplastic subjects with unresponsive blood pressure after PTRA were affected by primary hyperaldosteronism. Primary hyperaldosteronism was confirmed in 9% (4/44) of the atherosclerotic patients (19% of subjects with residual hypertension). No specific clinical features were associated with the subsequent blood pressure control.

CONCLUSIONS

Primary hyperaldosteronism is a frequently neglected cause of residual hypertension despite technically successful endovascular treatment of renal artery disease.