Robert H. Wilkinson

Prospective analysis of strategies for diagnosing renovascular hypertension.

Renovascular hypertension is a potentially curable form of high blood pressure. However, it is unclear how best to select patients who are likely to have renovascular hypertension, what diagnostic strategy to use in these selected patients, and how to predict the hemodynamic significance of a renal artery stenosis. We determined the prevalence of renovascular hypertension in adults who exhibited suggestive clinical features. In these clinically selected patients, we then determined the test characteristics of various diagnostic and potential screening tests. Renovascular hypertension was diagnosed if correction of renal artery stenosis resulted in decreased blood pressure. Of the 66 hypertensive adults evaluated, 11 (16.7%) had renovascular hypertension. Captopril-stimulated peripheral renln activity detected renovascular hypertension with 73% sensitivity, 72% specificity, 38% positive predictive value, and 92% negative predictive value. Less optimal combinations of sensitivity and specificity were found for differential glomerular filtration rate renography, differential effective renal plasma flow renography, and selective renal vein renin ratios, each performed after a single dose of captopril. Intravenous digital subtraction renal angktgraphy detected all patients with renovascular hypertension and was normal in 71% of patients with essential hypertension. To evaluate potential screening tests for renovascular hypertension, we calculated predictive values applied to a low prevalence population. If the observed sensitivities and specificities apply to a population with 5% prevalence of renovascular hypertension, captopril-stimulated peripheral renin would have a positive predictive value of 12% and a negative predictive value of 98%. In 16 patients with known renal artery stenosis, neither the captopril-stimulated renal vein renin ratio nor captopril-stimulated differential renography accurately predicted blood pressure response to correction of the stenosis. We conclude that clinical criteria can identify a subgroup with 16.7% prevalence of renovascular hypertension. In this high prevalence group, intravenous digital subtraction renal angiography will identify virtually all patients with renovascular hypertension, and a normal study will be sufficient to exclude renovascular hypertension. In unselected hypertensive patients, screening with captopril-stimulated peripheral renin activity may be the most useful and efficient procedure for identification of patients with renovascular hypertension. Functional tests do not accurately predict the hemodynamic significance of a renal artery stenosis.

Radioactive Chromic Phosphate Suspension: Studies on Distribution, Dose Absorption, and Effective Therapeutic Radiation in Phantoms, Dogs, and Patients'**

Abstract A series of studies in phantoms, dogs, and patients was undertaken to investigate physical properties of the commercial preparation of radioactive chromic phosphate suspension ( 32 P), distribution of intraperitoneally administered 32 P, and absorbed doses of 32 P by intraabdominal organs, surface tissues, and lymph nodes. Phantom studies revealed that premixing was necessary to obtain complete dispersion of the suspension. Bremsstrahlung imaging in dogs and patients suggested that this modality was effective in imaging the dispersion of 32 P, and the predicted localization in the peritoneal cavity and later the thoracic lymph nodes could be documented with this method. Autoradiographs, Geiger-Muller tissue counting, Bremsstrahlung imaging, and thermoluminescent dosimeter measurements in multiple dog experiments suggested that intraperitoneally administered 32 P suspension delivers superficial but probably therapeutic dosages to peritoneal surfaces as well as thoracic lymph nodes associated with drainage of peritoneal fluid. However, retroperitoneal structures such as pelvic and paraaortic lymph nodes receive minimal dosages of radiation from intraperitoneal 32 P suspension. These studies tend to confirm clinical data that intraperitoneal 32 P may be effective as adjunctive treatment in early stage ovarian carcinoma, but should not be used when the risk of retroperitoneal lymph node involvement is high or when residual intraperitoneal macroscopic disease is present.

NONOBSTRUCTIVE DILATATION OF UPPER URINARY TRACT MAY LATER CONVERT TO OBSTRUCTION

We report on 5 babies found to have pyelocaliectasis or hydroureteronephrosis antenatally who were evaluated soon after birth because of persistent mild or moderate upper urinary tract dilatation. In each instance, vesicoureteral reflux was absent and the technetium-99m diethylenetriaminepentaacetic acid renal scan revealed good function in the ipsilateral kidney. Renogram curves, after furosemide, did not show an obstructed pattern. Indeed, allowing for the dilatation, the drainage patterns were thought to be normal. In each instance the patient represented or was found on follow-up to have increased dilatation. Renograms were then repeated, using the same radiopharmaceutical and dose of diuretic. An obstructive pattern was seen in each instance. These significant observations demonstrate that nonobstructive hydronephrosis, diagnosed prenatally, may later convert to obstruction at the ureteropelvic junction (UPJ) or in the juxtavesical ureter (UVJ). Thus, careful follow-up, for a period yet to be determined, is desirable in patients in whom the initial postnatal evaluation does not demonstrate obstruction by current criteria.

Intraperitoneal chromic phosphate P 32 as salvage therapy for persistent carcinoma of the ovary after surgical restaging

From 1977 through 1984, 23 patients with persistent epithelial carcinomas of the ovary received intraperitoneal instillation with chromic phosphate P 32 suspension as salvage therapy after second- or third-look laparotomy. Patients received a median 10 cycles of chemotherapy before chromic phosphate P 32. Disease consisted of microscopic residual only in 10 patients (43%), macroscopic residual that was completely resected in eight (35%), and macroscopic residual disease in which the largest diameter was less than 0.5 cm in five patients (22%). Ten patients are free of disease at 13 to 94 months after chromic phosphate P 32 salvage therapy. Life table survival is 75% at 2 years and 57% at 4 years, with a disease-free survival rate of 54% at 2 years and 27% at 4 years. Patients with no gross residual disease had median disease-free survival of 27 months versus 9 months for patients with macroscopic residual disease (p greater than 0.1). Only three patients (13%) developed surgical bowel complications related to chromic phosphate P 32. Compared with previous studies, intraperitoneal chromic phosphate P 32 as salvage therapy for patients with minimal residual ovarian carcinoma defined at secondary surgical evaluation results in comparable survival and fewer complications than does salvage abdominopelvic irradiation and should be considered as an option to further chemotherapy in selected patients.

Comparison of intravenous digital subtraction angiography and conventional arteriography in defining renal anatomy.

Intravenous digital subtraction renal angiography (IV-DSRA) is frequently used in the preoperative evaluation of living-related (LR) kidney donors. However, the true accuracy of IV-DSRA in the donor population is difficult to assess since abnormalities of the kidney and its circulation are uncommon in this group. Therefore, we evaluated IV-DSRA in a group of patients more likely to have anomalies and abnormalities that would affect LR donor selection, donor nephrectomy, and subsequent transplantation. Hypertensive adults being evaluated for renovascular hypertension had IV-DSRA and conventional renal arteriograms, which were interpreted independently. We determined the accuracy of IV-DSRA, compared with conventional arteriography, in detecting multiple renal arteries, renal artery stenosis, fibromuscular dysplasia, and abnormal renal parenchyma. Technically unsatisfactory studies were excluded from analysis. Of 59 patients evaluated, 37 had abnormalities or anomalies. IV-DSRA failed to detect 28 of 50 findings in these 37 patients. In 21 patients with multiple renal arteries, IV-DSRA underestimated the number of main renal arteries in 8. Significant renal artery stenosis, present in 16 patients, was undetected by IV-DSRA in 3 of these patients. Mild fibromuscular dysplasia was not detected by IV-DSRA in any of the 5 patients with this condition, and abnormalities of renal parenchyma were not detected in 6 of the 8 patients with scarred or cystic kidneys. When compared with conventional renal arteriography in a hypertensive population, the IV-DSRA does not accurately detect abnormalities of the kidney and its circulation. If these data are confirmed in nonhypertensive subjects, preoperative evaluation of LR kidney donors using IV-DSRA alone may fail to detect potentially important anatomic abnormalities.Intavenous digital subtraction renal angiography (IV-DSRA) is frequently used in the preooperative evaluation of living-related (LR) kindney donors. However, the true accuracy of IV-DSRA in th donor population is difficult to assess since abnormalities of the kidney and its circulation are uncomon in this group. Therefore, we evaluated IV-DSRA in a group of patients more likely to have anomalies and abnormalities that would affect LR donor selction, donor nephrectomy, and subsequent transplantation. Hypertensive adults being evaluated for renovascular hypertension had IV-DSRA and conventional renal arteriograms, which were interpreted indepenmdently. We determinded the accuracy of IV-DSRA, compared with conventional arteriography, in detecting multiple renal arteries,l renal artery stenosis, fibromuscular dysplasia, and abnormal renal parentchyma. Technically unsatisfactory studies were excluded from analysis. Of 59 patients evaluted, 37 had abnormalities or anomalies. IV-DSRA failed to detect 28 of 50 findings in these 37 patients. In 21 patients with multiple renal arteries, IV-DSRA underestimated the number of main renal artery stenosis, present in 16 patients, was undetected by IV-DSRA in 3 of these patients. Mild fibromuscular dysplasia was not detected by IV-DSRA in any of the 5 patients with this condition, and abonormalties of renal parenchyma were not detected in 6 of the 8 patients with scarred or cystic kidneys. When compared with conventional renal arteriography in a hypertensive population, the IV-DSRA does not accurately detect abormalities of the kidney and its circulation. It these data are confirmed in nonhypertensivse subjects, preopertive evaluation of LR kindney donors using IV-DSRA alone may fail to detect potentially important anatomic abormalities.

Osteoporotic sacral fractures: A clinical study

Traumatic sacral fractures are most often due to motor vehicle or industrial accidents and are commonly associated with pelvic, urogenital, and neurological injuries. In recent years, a more subtle type of sacral fracture, not associated with major trauma, has been described. It is an osteoporotic insufficiency fracture that presents as low back pain in elderly patients, especially postmenopausal Caucasian women. It may escape detection unless radionuclide bone scans, tomograms, or computed tomograms are obtained. The radiographic features have been detailed in various publications, but little has been reported about the clinical features, treatment, or ultimate outcome of patients with osteoporotic sacral fractures. We have reviewed the charts and radiological studies of 13 women and 3 men who sustained this type of fracture between 1983 and 1986. All of these patients were Caucasian. The average age was 71 years. The most common presenting symptom complex was diffuse low back pain accompanied by hip, buttock, or thigh pain. Pertinent physical findings were limited to tenderness on palpation of the sacrum and a decreased range of low back motion. The osteoporotic fractures were seldom noted on plain roentgenograms of the sacrum, but were readily defined by sacral tomography or computed tomography. Radionuclide bone scanning also proved helpful in making the diagnosis by localizing the process. Treatment was medical and consisted of therapies designed to reduce pain and to combat the associated osteopenia. Of our 16 patients, 11 had complete pain relief, 2 had substantial pain relief, 2 noted decreasing pain before they died of other causes, and 1 was followed less than 1 month.(ABSTRACT TRUNCATED AT 250 WORDS)