Clinical insights into the diagnosis and management of renovascular disease. An evidence-based review.

Renovascular disease is a common, but complex disorder, the most common causes of which are fibromuscular dysplasia and atherosclerosis. It usually presents in 1 of 3 forms: asymptomatic renal artery stenosis, renovascular hypertension, or ischemic nephropathy. The clinical index of suspicion remains paramount in developing an appropriate diagnostic strategy. Although subject to certain limitations, conventional contrast angiography is usually considered the gold standard in confirming the diagnosis. In addition, there are a number of available non-invasive tests that can aid in decision-making. These tests can be divided into those that detect the anatomic presence of a stenosis and those that identify the functional consequences of the renal artery obstruction. No one study is appropriate for every patient. Treatment options include medical, surgical or percutaneous approaches. Generally, in patients with fibromuscular disease the results of surgery and percutaneous approaches appear superior. In patients with atherosclerotic disease, the data are less consistent, and there does appear to be a group of patients who will respond well to medical management. Potential diagnostic algorithms for diagnosis and treatment are presented in this review.

Ostial renal artery stent placement in patients 75 years of age or older.

Renal artery stent placement has been shown to improve blood pressure (BP) and stabilize renal function in patients with atherosclerotic renovascular disease. However, limited data are available in patients > or = 75 years of age. We analyzed the prestent characteristics and clinical outcomes of patients aged > or = 75 years who underwent renal artery stenting at our institution. We compared these data with those from the remainder of our stent cohort. Nineteen of 89 (21.3%) stent patients were > or = 75 years old. Before intervention, those > or = 75 years were significantly more likely to be women (84.2% v 55%; P = .02), current or former smokers (78.6% v 36.8%; P = .002), and on a greater number of antihypertensive medications (3.68 v 2.80; P = .048). Average clinical follow-up was similar in both groups (23.9 v 23.2 months; P > .05). At last available follow-up, there were more deaths in those > or = 75 years (7/19 v 5/70; P = .038). No significant difference was found in the incidence of dialysis after intervention (3/19 v 7/70). Seventy-four percent of those > or = 75 years had improved BP, 21% were stable, and 5% were worse. Renal function was improved in 26%, stable in 53%, and worse in 21%. Among those > or = 75 years, there was a significant decrease in systolic BP (186.9 to 144.4; P < .01). There was a trend toward decreased diastolic BP and medications. These clinical results did not differ significantly from patients <75 years. Patients > or = 75 years of age with atherosclerotic renovascular disease have a higher incidence of mortality 2 years after renal artery stent placement, but they seem to derive clinical benefit comparable to younger patients.

An evidence-based approach to diagnosing renovascular hypertension.

Making the diagnosis of potentially reversible renovascular hypertension can be problematic. Although there are a number of noninvasive screening tests available, no one study is appropriate for every patient. In general, the available tests can be divided into those that identify the functional consequences of a renal artery obstruction (angiotensin-converting enzyme inhibitor-augmented renography) and those that identify the anatomic presence of stenosis (duplex ultrasonography, magnetic resonance angiography, and contrast tomography angiography). The most appropriate diagnostic approach is based largely on the clinical index of suspicion, the potential etiology of the renal artery lesion (fibromuscular dysplasia or atherosclerosis), and the individual patient's physiology and presentation. A potential treatment algorithm is presented.

Type B aortic dissection complicating renal artery angioplasty and stent placement.

Percutaneous renal artery stent placement has been demonstrated to improve blood pressure control and stabilize renal function in patients with atherosclerotic renal artery disease. However, this procedure is not without risk of significant morbidity, and its effectiveness, as compared to alternative treatments, has not been adequately established. The authors report a case of acute type B aortic dissection complicating renal artery stent placement. The authors postulate that an intimal disruption occurred during initial balloon angioplasty, and that repeated application of radial, shear, and torque forces during stent placement may have extended the injury. The diagnosis of acute aortic dissection should be considered in patients with suggestive symptoms immediately after stent placement.

Renal vascular disease: medical management, angioplasty, and stenting.

In the absence of large, prospective, quality randomized trials, there remains tremendous debate concerning the optimal management of patients with renal vascular disease. This debate is compounded by the fact these patients do not represent a homogeneous group; different causes and presentations each carry a different prognosis and potential response to therapy. Therapeutic options include medical management, surgery, or percutaneous approaches (angioplasty or stenting). This review examines the results of observational studies of medical and percutaneous therapies for blood pressure control and preservation of renal function. Generally, in patients with fibromuscular disease, the results of percutaneous management are superior to medical therapy. Although these observational studies are difficult to compare, in patients with atheromatous disease, the results with interventional and medical therapy appear roughly similar. There have been three randomized prospective trials of routine angioplasty versus medical management. These trials show little advantage to interventional therapies in those patients whose blood pressure is well controlled with medication who do not show progression of renal insufficiency during medical management. Based on these data, this review outlines a potential management strategy that relies on an individualized risk benefit assessment.

Prevention of recurrent pulmonary edema in patients with bilateral renovascular disease through renal artery stent placement.

Pulmonary edema and congestive heart failure (both referred to here as PE) have been reported to be complications of bilateral renal artery stenosis or unilateral stenosis in a solitary functioning kidney (both referred to as BRAS). The goals of this study were to determine whether a history of PE was more common in patients with BRAS than in those with unilateral stenosis and a normal contralateral kidney (URAS), and whether recurrent PE could be prevented by renal artery stent placement. We evaluated 90 consecutive patients with renovascular disease who were treated with percutaneous renal artery stent placement. History and clinical follow-up were obtained through chart review and phone contact with referring physicians. Mean follow-up was 18.4 months after stent placement. Twenty-three of 56 (41%) subjects with BRAS had a history of PE before revascularization, compared with four of 34 (12%) subjects with URAS (P = .05). Twenty-five of the 27 patients with history of PE had adequate clinical follow-up. Seventeen of the 22 (77%) subjects with BRAS and history of PE had no further PE after stent placement in one or both renal arteries. The five BRAS subjects with recurrent PE after stent placement had evidence of stent thrombosis or restenosis. In contrast, only one of three (33%) URAS subjects with a history of PE remained free of PE after stent placement. We conclude that PE is a common complication of BRAS, but not of URAS. In patients with BRAS, recurrent PE can be prevented by successful stent placement in one or both renal arteries.

Longitudinal study of error prevalence in Pennsylvania physicians' office laboratories.

We examined the results of the low-volume-laboratory proficiency testing program for new physician office participants in the Commonwealth of Pennsylvania. Serum glucose, hemoglobin, urinalysis, throat culture, urine culture, and Gram's stain were included in the study. Quarterly error rates for each analyte were determined; between one fourth and all of the laboratories that made at least one error during the first two quarters of proficiency testing made at least one more error in the same analyte during the subsequent two quarters. We show that participation in the quarterly proficiency testing program for a 12- to 15-month period did not lead to a measurable increase in performance. For proficiency testing to be effective, we suggest that it be supplemented by additional methods to lower error rates, such as regulation or intensive consultation and training services for personnel of physicians' office laboratories.

Polypoid synovial sarcoma of the esophagus.

Pure sarcomas of the esophagus are exceedingly rare. We report a case of esophageal synovial sarcoma which occurred in an adolescent. The tumor was locally resected, sparing the patient esophagectomy. After postoperative radiation therapy, the patient remains alive and well without evidence of disease 28 mo after operation. The unique nature of polypoid sarcoma of the esophagus, and the potential for cure without esophagectomy, is discussed.

MURCS association with additional congenital anomalies.

The postmortem findings in a patient with the MURCS association (müllerian duct aplasia/hypoplasia, renal agenesis or ectopy, and cervicothoracic somite dysplasia) are reported. This is the first autopsy study since the syndrome was recognized. The autopsy revealed abnormalities of the venous, pulmonary, and central nervous systems that had not been reported previously in patients with this syndrome. A review of the literature suggested that although the MURCS association usually occurs sporadically, as in this case, a familial association is occasionally present. In some cases the MURCS association may be a genetically determined pleiotropic condition.

Mesonephric adenocarcinoma of the bladder.

Mesonephric adenocarcinoma of the bladder may be the malignant counterpart of nephrogenic adenoma. We report the third known case of this invasive, well differentiated, tubular neoplasm resembling nephrogenic adenoma. The invasive potential of nephrogenic neoplasms has altered our approach to the management of these lesions. Nephrogenic adenoma and mesonephric adenocarcinoma appear cytologically similar on a superficial bladder biopsy. The latter is excluded by deeper bladder biopsies. Muscular invasion may indicate a more aggressive behavior and may require radical cystectomy for cure.