[Management of renal atrophy in hypertensive patients: experience in Lille]

Selective venous sampling for secondary hypertension

Selective venous sampling (SVS), an invasive radiographic procedure that depends on contrast media, holds a unique role in diagnosing and guiding the treatment of certain types of secondary hypertension, particularly in patients who may be candidates for curative surgery. The adrenal venous sampling (AVS), in particular, is established as the gold standard for localizing and subtyping primary aldosteronism (PA). Throughout decades of clinical practice, AVS could be applied not only to PA but also to other endocrine diseases, such as adrenal Cushing syndrome (ACS) and Pheochromocytomas (PCCs). Notably, the application of AVS in ACS and PCCs remains less recognized compared to PA, with the low success rate of catheterization, the controversy of results interpretation, and the absence of a standardized protocol. Additionally, the AVS procedure necessitates enhancements to boost its success rate, with several helpful but imperfect methods emerging, yet continued exploration remains essential. We also observed renal venous sampling (RVS), an operation akin to AVS in principle, serves as an effective means of diagnosing renin-dependent hypertension, aiding in the identification of precise sources of renin excess and helping the selection of surgical candidates with renin angiotensin aldosterone system (RAAS) abnormal activation. Nonetheless, further basic and clinical research is needed. Selective venous sampling (SVS) can be used in identifying cases of secondary hypertension that are curable by surgical intervention. Adrenal venous sampling (AVS) and aldosterone measurement for classificatory diagnosis of primary aldosteronism (PA) are established worldwide. While its primary application is for PA, AVS also holds the potential for diagnosing other endocrine disorders, including adrenal Cushing's syndrome (ACS) and pheochromocytomas (PCCs) through the measurements of cortisol and catecholamine respectively. In addition, renal venous sampling and renin measurement can help to diagnose renovascular hypertension and reninoma.

The efficacy of unilateral laparoscopic nephrectomy in the pediatric hypertensive patient

BACKGROUND

Secondary hypertension due to a poorly functioning or non-functional kidney may be refractory to medical management. In such cases, nephrectomy can improve or cure hypertension. With the routine use of laparoscopy, nephrectomy can be performed in a minimally invasive manner, but surgery still carries inherent risks and complications.

OBJECTIVE

The objective of this study is to evaluate the outcomes of laparoscopic nephrectomy performed for secondary hypertension and identify potential predictors of postoperative hypertension resolution.

METHODS

After obtaining approval from institutional review board, patients from January 2002 to March 2018 who underwent laparoscopic nephrectomy were identified using Current Procedural Technology codes. All charts were then manually reviewed to isolate those patients with secondary hypertension present preoperatively. Patient demographics, urologic history, and laboratory and imaging findings were recorded for all patients. Serial blood pressures were recorded at all renal visits along with any antihypertensive medication changes. Postoperative outcomes and complications were also noted for all patients.

RESULTS

A total of 20 patients (7 girls, 13 boys) underwent laparoscopic nephrectomy to treat hypertension at an average age of 10.6 years (range 1.7-17.0 years). Etiology of a solitary non-functional kidney was vesicoureteral reflux in 10 of 20 patients, multicystic dysplastic kidney in 5 of 20, ureteropelvic junction obstruction in 2 of 20, ureteral obstruction in 1 of 20, and renal artery stenosis in 2 of 20 patients. At time of surgery, 3 of 20 patients were on two antihypertensives, 10 of 20 were on one antihypertensive, and 7 of 20 proceeded to surgery with no medical management. In the 30-day postoperative period, no complications were noted. Hypertension improved in 10 of 20 (50%) patients, all of whom were not on any antihypertensive medications after surgery. Hypertension persisted in 4 of 20 (20%) patients, requiring the same antihypertensive regimen and worsened in 6 of 20 (30%) patients, requiring increased doses and/or additional antihypertensives. Average follow-up time was 2.7 years. No significant predictors of postoperative hypertension result were identified when comparing the groups of responders and non-responders.

DISCUSSION

While laparoscopic nephrectomy for a non-functioning kidney in the setting of hypertension is a safe procedure, the cure rate for hypertension in the cohort appears to be on the low side of what was previously reported. While the small sample size is a main limitation, it is among the largest sample sizes for pediatric hypertensive patients. Previously shown predictors were not predictive in the similar-sized cohort.

CONCLUSIONS

Patients should be carefully counseled on the risks and benefits of nephrectomy to treat hypertension, the importance of continued follow-up after nephrectomy, and the possible need for chronic medical management with antihypertensives.