succimer and Hypertension--Renovascular

This article describes the role of nuclear medicine in the evaluation of the genitourinary tract. The technical aspects of radionuclide imaging (radiopharmaceuticals, radiation dosimetry, instrumentation, and method) are briefly presented, and each of the indications for renal scintigraphy--including the evaluation of differential renal function, hypertension, obstruction, renal transplants, masses, trauma, congenital anomalies, vesicoureteral reflux, and infection--are discussed. The relative advantages and disadvantages of radionuclide imaging with respect to alternative radiographic examinations (such as intravenous urography, ultrasonography, CT, angiography, and magnetic resonance imaging) are emphasized wherever applicable.

Topics: Graft Rejection; Humans; Hypertension, Renovascular; Iodohippuric Acid; Kidney; Kidney Function Tests; Kidney Neoplasms; Kidney Transplantation; Kidney Tubular Necrosis, Acute; Male; Organotechnetium Compounds; Pentetic Acid; Postoperative Complications; Pyelonephritis; Radioisotope Renography; Spermatic Cord Torsion; Succimer; Sugar Acids; Technetium; Technetium Tc 99m Dimercaptosuccinic Acid; Technetium Tc 99m Pentetate; Ureteral Obstruction; Urinary Tract; Vesico-Ureteral Reflux

To examine the value of plasma endothelin-1 (ET-1), we measured the level of plasma ET-1 activity of peripheral venous blood and selective renal venous blood in renovascular hypertension patients, and compared that activity with corresponding renin activity and split renal function.. ET-1 level, renin activity in selective renal venous blood and peripheral venous blood, and 99mTc-dimercaptosuccinic acid renal uptake as a split renal function test were measured in 11 patients (mean 42.1 years old) with renovascular hypertension (RVH) and 6 patients with both renal cell cancer (RCC) and essential hypertension.. 1. In patients with RVH, resting peripheral venous plasma ET-1 ranged from 0.6 to 8.1 (mean 4.07) pg/ml and was higher than the normal level (p <0.01). However, the renal vein ET-1 ratio was nor correlated with the renal vein renin ratio. 2. In patients with RCC, resting peripheral venous plasma ET-1 was not different from the normal level. There was no step-up of plasma ET-1, or renin among renal veins, or the proximal and distal parts of the interior vena cava. 3. Both renal vein renin ratio and renal vein ET-1 ratios were inversely correlated with t99mTC-dimercaptosuccinic acid renal uptake as a split renal function examination in patients with RVH. 4. The peripheral plasma ET-1 level was correlated with the degree of stenosis of the renal artery in patients with RVH of a unilateral lesion, but not bilateral lesions.. These results suggest that ET-1 may take part in the hypertensive mechanisms of RVH in addition to the renin-angiotensin system, but its significance in RVH still remains to be examined.

Topics: Adolescent; Adult; Aged; Antihypertensive Agents; Captopril; Child, Preschool; Endothelin-1; Female; Humans; Hypertension, Renovascular; Kidney; Male; Middle Aged; Organotechnetium Compounds; Radioimmunoassay; Radionuclide Imaging; Renal Artery; Renin; Succimer; Technetium Tc 99m Dimercaptosuccinic Acid

To examine the incidence, clinical and radiologic findings, and response to treatment of renovascular hypertension (RVHT) in moyamoya disease (MMD).. A retrospective analysis of medical records in six RVHT cases (8.3%) among 72 MMD patients observed from November 1987 to December 1995.. The age at onset of MMD ranged from 9 months to 7 years 1 month (mean, 3.3 years). The most common initial manifestation of MMD was transient ischemic attack. Hypertension was detected between 4 years 4 months and 12 years 3 months (mean, 7.87 years). Unstimulated plasma renin activity was elevated in all six cases. Renal ultrasonography and captopril technetium 99m-labeled dimercaptosuccinic acid scan showed abnormal findings in four of five and in three of four available studies, respectively. However, both imaging studies showed abnormal findings only in the most severely affected kidneys even with bilateral renal artery stenosis. Renal arteriography revealed bilateral lesions in three of the patients and unilateral lesions in the others. Renal angioplasty was performed in four cases but was successful in only one and partially successful in another. A renal artery specimen obtained during renal autotransplantation showed intimal fibroplasia. At the last follow-up, one patient had normal blood pressure without the use of antihypertensive agents, but the other five patients needed this medication to control blood pressure.. Because RVHT may be more commonly associated with MMD than has hitherto been appreciated, it is recommended that blood pressure be carefully followed and that diagnostic procedures for RVHT be carried out in hypertensive patients with MMD.

Topics: Adolescent; Angiography; Angiotensin-Converting Enzyme Inhibitors; Antihypertensive Agents; Biopsy; Blood Pressure; Captopril; Child; Child, Preschool; Female; Fibromuscular Dysplasia; Follow-Up Studies; Humans; Hypertension, Renovascular; Incidence; Infant; Ischemic Attack, Transient; Kidney; Kidney Transplantation; Male; Moyamoya Disease; Organotechnetium Compounds; Radionuclide Imaging; Radiopharmaceuticals; Renal Artery Obstruction; Renin; Retrospective Studies; Seizures; Succimer; Technetium Tc 99m Dimercaptosuccinic Acid; Tunica Intima; Ultrasonography

A 43-year-old female patient with hypertension was diagnosed as having one-kidney renovascular hypertension with dysfunction of the contralateral kidney, and percutaneous transluminal renal angioplasty was carried out. Marked polyuria was observed during the 2- to 72-hour postoperative period. During the 12- to 18-hour period of polyuria, the urine volume was 8.9 liters/6 h, which was 62% of the glomerular filtration, and was accompanied by high fractional excretion of sodium and of potassium and a high urine beta 2-microglobulin level. The mechanism of polyuria in this case is discussed.

Topics: Adult; Angioplasty, Balloon; Blood Pressure; Female; Humans; Hypertension, Renovascular; Organotechnetium Compounds; Polyuria; Postoperative Complications; Radiography; Radioisotope Renography; Renal Artery; Succimer; Technetium Tc 99m Dimercaptosuccinic Acid

Plasma endothelin-1 (ET-1)-like immunoreactivity in selective renal venous blood and peripheral venous blood was measured and compared with plasma renin activity and aldosterone level in a 26-year-old woman with suspected renovascular hypertension due to stenosis of the left renal artery. Although there was no significant step-up in plasma renin activity between the right and the left renal vein, left/right ratio of plasma ET-1 in the renal vein was 2.18. This case suggests that ET-1 may be one of the hypertensive mechanisms of suspected renovascular hypertension in addition to the renin-angiotensin system.

Topics: Adult; Aldosterone; Endothelins; Female; Humans; Hypertension, Renovascular; Kidney; Kidney Function Tests; Organotechnetium Compounds; Radioimmunoassay; Radionuclide Imaging; Renal Artery Obstruction; Renin; Succimer; Technetium Tc 99m Dimercaptosuccinic Acid

Captopril-enhanced renal scintigraphy with Tc-99m DMSA was performed in an 11-year-old boy with hypertension. This showed a significant reduction in function of the right kidney. Renal arteriography was performed and showed two renal arteries on the right, the major one with stenosis. This case illustrates the possible role that scintigraphy with Tc-99m DMSA can play in the diagnosis of renovascular hypertension.

Topics: Captopril; Child; Humans; Hypertension, Renovascular; Kidney; Male; Organotechnetium Compounds; Radiography; Radionuclide Imaging; Renal Artery; Renal Artery Obstruction; Sensitivity and Specificity; Succimer; Technetium Tc 99m Dimercaptosuccinic Acid

This is a report of serial Tc-99m DMSA renal imaging on a pediatric patient with renovascular hypertension that experienced a complication of angioplasty. The case dramatically illustrates the usefulness of this radiopharmaceutical in the evaluation of acutely worsening hypertension, and in monitoring improvement following arterial revascularization for significant branch stenosis.

Topics: Angioplasty, Balloon; Child; Humans; Hypertension, Renovascular; Kidney; Male; Organotechnetium Compounds; Radionuclide Imaging; Renal Artery; Renal Artery Obstruction; Succimer; Technetium Tc 99m Dimercaptosuccinic Acid

In children over 1 year of age, renal disease is the commonest cause of hypertension. Arteriography is considered the reference method to establish the diagnosis of renovascular disease; however, it is an invasive technique with a high radiation burden for children. This was a retrospective study of pre- and post-capto-technetium-99m dimercaptosuccinic acid (DMSA) imaging compared with arteriography in 18 children between the ages of 3 and 17 years. Alone, the 99mTc-DMSA scan is a sensitive indicator of renal parenchymal disease, although non-specific in suggesting the pathology. The combination of pre- and post-captopril studies may increase the sensitivity and specificity in the diagnosis of renovascular disease in the presence of hypertension. This work suggests that a screening investigation with a low radiation burden can be carried out at most institutions; if the investigation is positive, there will be a high index of suspicion that renovascular disease is the cause of the hypertension.

Topics: Adolescent; Angiography; Captopril; Child; Child, Preschool; Female; Humans; Hypertension, Renovascular; Male; Organotechnetium Compounds; Radionuclide Imaging; Retrospective Studies; Sensitivity and Specificity; Succimer; Technetium Tc 99m Dimercaptosuccinic Acid

We present a case in which a 39-year-old woman with correctable bilateral renovascular hypertension did not show abnormality during post-captopril technetium-99m dimercaptosuccinic acid (DMSA) study. Post-captopril 99mTc-diethylene triamine penta-acetic acid (DTPA) scintigraphy revealed the adverse effect of a stenosis of the artery supplying the upper part of her left kidney but failed to uncover the existence of severe multiple narrowings of the right renal artery. After bilateral renovascular reconstructive surgery, the hypertension completely disappeared. This case illustrates that DTPA may be more efficacious than DMSA in the detection of segmental loss of renal function induced by angiotensin converting enzyme inhibition.

Topics: Adult; Captopril; Female; Humans; Hypertension, Renovascular; Organotechnetium Compounds; Radionuclide Imaging; Succimer; Technetium Tc 99m Dimercaptosuccinic Acid; Technetium Tc 99m Pentetate

The effect of rapid converting enzyme inhibition (CEI) with intravenous enalaprilat on technetium-99m-(99mTc) diethylenetriaminepentaacetic acid (DTPA) and 99mTc-dimercaptosuccinic acid (DMSA) renograms was evaluated in rats with two-kidney, one-clip renovascular hypertension. Rapid sequential DTPA renograms, performed immediately before and five minutes after enalaprilat injection (30 micrograms/kg), demonstrated a selective decrease in clipped kidney DTPA plasma clearance following CEI and no significant effect on unclipped kidney function. Pre- and post-CEI data were obtained with a single injection of DMSA by administering enalaprilat five minutes after the radiopharmaceutical. Enalaprilat slowed the rate of DMSA accumulation in clipped relative to unclipped kidneys, and reduced the clipped/unclipped kidney ratio of absolute DMSA uptake at 10 and 30 min. DTPA and DMSA were equally effective in demonstrating the CEI effect. Enalaprilat was also compared with captopril (3 mg/kg, intraperitoneally), using sequential DTPA renograms. Clipped kidney DTPA plasma clearance was reduced to an identical degree (40%) by both converting enzyme inhibitors. Clinical renographic protocols can probably be devised to take advantage of the rapid, reliable CEI of enalaprilat, thereby shortening total procedure time.

Topics: Animals; Enalaprilat; Furosemide; Hypertension, Renovascular; Kidney; Male; Organotechnetium Compounds; Pentetic Acid; Radioisotope Renography; Rats; Rats, Inbred Strains; Succimer; Technetium Tc 99m Dimercaptosuccinic Acid; Technetium Tc 99m Pentetate; Time Factors

Iodine-123 hippurate renography, [99mTc]diethylenetriaminepentaacetic acid (DTPA) renography, and [99mTc]dimercapto succinic acid (DMSA) renal scintigraphy were performed before and during angiotensin converting enzyme (ACE) inhibition in a group of 15 hypertensive patients with angiographically "significant" unilateral renal artery stenosis. Visual and quantitative evaluation of the three radioisotope methods before ACE inhibition already disclosed abnormalities suggestive of renal artery stenosis in a high percentage (87%, 60%, and 60%, respectively) in this group of patients, but ACE inhibition further improved the diagnostic yield in all three methods (93%, 86%, and 80%). Iodine-123 hippurate renography was at least as useful as [99mTc]DTPA renography in this respect, while [99mTc]DMSA scintigraphy can be used particularly in segmental stenosis. Despite a large drop in blood pressure after ACE inhibition little adverse reactions were seen and overall renal function was fairly well maintained, the exceptions noted in patients with initially a more impaired renal function.

Topics: Adolescent; Adult; Angiotensin-Converting Enzyme Inhibitors; Blood Pressure; Drug Evaluation; Enalapril; Female; Humans; Hypertension, Renovascular; Iodohippuric Acid; Kidney; Male; Middle Aged; Organometallic Compounds; Pentetic Acid; Radionuclide Imaging; Renal Artery Obstruction; Succimer; Technetium; Technetium Tc 99m Dimercaptosuccinic Acid; Technetium Tc 99m Pentetate

Quantitative renal imaging is subject to errors related to varying renal depth. Lateral projection images, ultrasound, and geometric mean calculations can be utilized to measure renal depth or to correct for variations in the attenuation of renal activity. However, each of these methods is time consuming and each has the potential for introducing additional errors. As an alternative, the authors propose the use of quantitative indices that are insensitive to the effects of attenuation. This report illustrates how transit-time-distribution (TTD) parameters can be used to assess renal perfusion independent of varying renal depth.

Topics: Humans; Hypertension, Renovascular; Kidney; Male; Middle Aged; Organometallic Compounds; Pentetic Acid; Radionuclide Imaging; Renal Circulation; Succimer; Technetium; Technetium Tc 99m Dimercaptosuccinic Acid; Technetium Tc 99m Pentetate

Critical factors determining the renal handling of 99mTc-dimercaptosuccinic acid (DMSA) are protein binding in plasma and the renal 99mTc-DMSA extraction efficiency. Comparison of the count rate over soft tissue with that over the cardiac blood pool about 1 h after injection demonstrated that 99mTc-DMSA is not exclusively an intravascular label. 99mTc-DMSA was 76% protein bound in plasma as demonstrated by HPLC and gel filtration. Assuming that the 24% that is not protein bound is filtered at the glomerulus, the renal extraction efficiency of 99mTc-DMSA by glomerular filtration is about 5%. Since the total renal extraction efficiency was also found to be about 5%, the majority of the activity that becomes fixed in the renal cortex arrives there as a result of filtration followed by tubular reabsorption rather than by direct extraction from peritubular blood. However, discordant changes in DMSA and DTPA uptake induced by captopril in renovascular hypertension (RVH) suggested that a minority of uptake was by direct peritubular extraction. This kinetic model was supported by indirect measurement of protein binding and extraction efficiency based on the kinetics of 99mTc-DMSA disappearance from plasma and kinetics of uptake in the kidneys. Furthermore, differential functional studies based on 99mTc-DMSA and 99mTc-DTPA before and after captopril in patients with RVH due to unilateral renal artery stenosis confirmed filtration followed by tubular reabsorption as the predominant route for DMSA uptake by the kidney.

Topics: Adult; Captopril; Child; Humans; Hypertension, Renovascular; Kidney Tubules; Organometallic Compounds; Protein Binding; Radionuclide Imaging; Succimer; Sulfhydryl Compounds; Technetium; Technetium Tc 99m Dimercaptosuccinic Acid