Glomerular filtration rate measured by 51Cr-EDTA clearance: evaluation of captopril-induced changes in hypertensive patients with and without renal artery stenosis

INTRODUCTION: Renal artery stenosis can lead to renovascular hypertension; however, the detection of stenosis alone does not guarantee the presence of renovascular hypertension. Renovascular hypertension depends on activation of the renin-angiotensin system, which can be detected by functional tests such as captopril renal scintigraphy. A method that allows direct measurement of the baseline and post-captopril glomerular filtration rate using chromium-51 labeled ethylenediamine tetraacetic acid (51Cr-EDTA) could add valuable information to the investigation of hypertensive patients with renal artery stenosis. The purposes of this study were to create a protocol to measure the baseline and post-captopril glomerular filtration rate using 51Cr-EDTA, and to verify whether changes in the glomerular filtration rate permit differentiation between hypertensive patients with and without renal artery stenosis. METHODS: This prospective study included 41 consecutive patients with poorly controlled severe hypertension. All patients had undergone a radiological investigation of renal artery stenosis within the month prior to their inclusion. The patients were divided into two groups: patients with (n=21) and without renal artery stenosis, (n=20). In vitro glomerular filtration rate analysis (51Cr-EDTA) and 99mTc-DMSA scintigraphy were performed before and after captopril administration in all patients. RESULTS: The mean baseline glomerular filtration rate was 48.6±21.8 ml/kg/1.73 m² in the group wuth renal artery stenosis, which was significantly lower than the GFR of 65.1±28.7 ml/kg/1.73m² in the group without renal artery stenosis (p=0.04). Captopril induced a significant reduction of the glomerular filtration rate in the group with renal artery stenosis (to 32.6±14.8 ml/kg/1.73m², p=0.001) and an insignificant change in the group without RAS (to 62.2±23.6 ml/kg/1.73m², p=0.68). Scintigraphy with technetium-99m dimercapto-succinic acid (DMSA) did...

Relationship between excretion of 51Cr-EDTA and mucositis in patients with 5-FU based chemotherapy / 대한내과학회지

BACKGROUND: Administration of anticancer drugs may damage gastrointestinal epithelium, thereby increasing the permeability of the gastrointestinal mucosa. It is known that intestinal permeability test using 51Cr-EDTA is a useful test to assess the damage of intestine. The aim of this study was to evaluate intestinal permeability in patients who were treated with 5-fluorouracil (5-FU) based chemotherapy and to evaluate the relationship between the excretion of 51Cr-EDTA and the grading of mucositis. METHODS: Twenty eight patients who were treated with 5-FU based chemotherapy were chosen as study cases while 18 healthy volunteers as controls. Intestinal permeability was assessed by measurement of the urinary excretion of 51Cr-EDTA after oral challenge, and the National Cancer Institute common toxicity criteria were used for assessing oral mucositis. RESULTS: All except 3 patients in the chemotherapy group experienced grade 1~3 stomatitis. The median value of intestinal permeability test was significantly higher in the chemotherapy group than in control group (7.61%, range 2.10-22.92 vs 2.17%, range 1.16-2.76, respectively, p<0.001). The grading of oral mucositis did correlate with the urinary excretion of 51Cr-EDTA (p<0.001, r=0.867). CONCLUSIONS: The measurement of 51Cr-EDTA excretion after oral challenge may be a useful test for evaluating the intestinal permeability by chemotherapy induced intestinal mucosal damage. Testing of intestinal permeability using 51Cr-EDTA may be applicable to evaluate the effect of therapeutic trials in patients with chemotherapy induced mucositis.