MR-derived renal morphology and renal function in patients with atherosclerotic renovascular disease.

Appropriate selection of patients with atherosclerotic renovascular disease (ARVD) for revascularization might be improved if accurate non-invasive investigations were used to assess severity of pre-existing parenchymal damage. The purpose of this study was to evaluate the associations between magnetic resonance imaging (MRI)-measured renal morphological parameters and single-kidney glomerular filtration rate (GFR) in ARVD. Three-dimensional (3D)-MRI was performed on 35 ARVD patients. Renal bipolar length (BL), parenchymal volume, parenchymal (PT), and cortical thicknesses (CT) were measured in 65 kidneys. Thirteen kidneys were supplied by normal vessels, 13 had insignificant (<50%) renal artery stenosis (RAS), 33 significant (>or=50%) RAS, and six complete vessel occlusion. All patients underwent radioisotopic measurement of single-kidney GFR (isoSK-GFR). Overall, 3D parameters such as parenchymal volume were better correlates of isoSK-GFR (r=0.86, P<0.001) than BL (r=0.78, P<0.001), PT (r=0.63, P<0.001) or CT (r=0.60, P<0.001). Kidneys with >or=50% RAS did show significant reduction in mean CT compared to those supplied by normal vessel (5.67+/-1.63 vs 7.28+/-1.80 mm, P=0.002; 22.1% reduction) and an even greater loss of parenchymal volume (120.65+/-47.15 vs 179.24+/-86.90 ml, P<0.001; 32.7% reduction) with no significant reduction in BL. In a proportion of >or=50% RAS kidneys, a disproportionately high parenchymal volume to isoSK-GFR was observed supporting a concept of 'hibernating parenchyma'. 3D parameters of parenchymal volume are stronger correlates of isoSK-GFR than two-dimensional measures of BL, PT or CT. 3D morphological evaluation together with isoSK-GFR might be useful in aiding patient selection for renal revascularization. Kidneys with increased parenchymal volume to SK-GFR might represent a subgroup with the potential to respond beneficially to angioplasty.

The importance of associated extra-renal vascular disease on the outcome of patients with atherosclerotic renovascular disease.

Atherosclerotic renovascular disease (ARVD) is a disease of ageing. It is usually a manifestation of widespread vascular disease and although it may be symptomless, many patients with ARVD present with the effects of extra-renal vascular disease, such as peripheral vascular (PVD), coronary heart (CHD) and cerebrovascular disease. ARVD is a common cause of hypertension and chronic renal failure (CRF), and it is one of the most common renal diagnoses in elderly patients accepted on to dialysis programmes with end-stage renal failure (ESRF). The cause of renal impairment in these patients is still a matter of debate. Patients with ARVD have a high mortality, especially those with renal failure. In this review we examine the relationships between ARVD and co-morbid extra-renal vascular disease, and the impact of these associated vascular pathologies upon renal functional and mortality outcomes is considered. The latest evidence concerning the likely pathogenesis of renal dysfunction in patients with ARVD is also reviewed.

Increasing the diagnostic yield of renal angiography for the diagnosis of atheromatous renovascular disease.

Atheromatous renovascular disease (ARVD) is a common cause of hypertension and chronic renal failure (CRF). In this unit, intravenous digital subtraction angiography (DSA) (or intraarterial DSA if indicated) is used as a screening angiographic study when ARVD is suspected. However, increased use of these investigations has resulted in a longer waiting time for angiography. As the majority of studies are negative for ARVD, clinical features and results of investigations of patients undergoing angiography were reviewed to identify those having the greatest likelihood of ARVD. The clinical notes were reviewed for all 249 patients undergoing angiography over an 18-month period. Primary indications for investigation were: hypertension 71 (28.5%), CRF 156 (62.7%) and CRF with severe hypertension 22 (8.8%). 12 of the CRF patients had end-stage renal failure. 166 (66.7%) patients had no evidence of ARVD, while only 83 (33.3%) patients showed some degree of ARVD, 29 (35%) of which had bilateral renal artery disease. There was no significant difference between the ARVD group and the non-ARVD group for mean age (69.0 years vs 63.3 years), male to female ratio, history of smoking (68.7% vs 55.4%), severe hypertension (10.8% vs 9.0%), hypercholesterolaemia (61.4% vs 47.0%), diabetes mellitus (28.6% vs 25.3%) or angiotensin converting enzyme inhibitor-related renal dysfunction (9.6% vs 6.1%). More patients in the ARVD group were investigated for CRF than in the non-ARVD group, as reflected by the higher serum creatinine level and the lower creatinine clearance in the ARVD group. 55 (33.1%) of the non-ARVD patients had no comorbid vascular disease, vascular bruits or ultrasound discrepancy in the size of the two kidneys, whereas all ARVD patients had at least one of these features (negative predictive value 100%). All three features were present in 19.3% of ARVD patients but in only 3.0% of the non-ARVD patients (positive predictive value 76.2%, specificity 97%). We plan to rationalize the criteria for angiography in the light of these findings, anticipating an increase in the diagnostic yield of renal angiography from its current 33.3% to above 42%.

Relationship of renal dysfunction to proximal arterial disease severity in atherosclerotic renovascular disease.

BACKGROUND: Renal impairment is common in patients with atherosclerotic renovascular disease (ARVD), but its pathogenesis is uncertain. This study investigated whether any relationship existed between renal function and the severity of proximal renal arterial lesions in patients with ARVD. METHODS: A cohort of 71 patients had creatinine clearance measured at the time of digital subtraction angiography; eight patients were diabetics and were excluded from further analysis. The severity of proximal renovascular lesions was estimated by standard methodology, and patients were sub-grouped according to residual patency of the proximal renal arteries (e.g. normal=2.0; unilateral occlusion )RAO(=1.0). Renal bipolar lengths at ultrasound were also assessed. RESULTS: Sixty-three non-diabetic patients (mean+/-SD age 67.7+/-5.8 years; 34 males) were suitable for study. No differences in renal function (mean+/-SD creatinine clearance (ml/min)) were seen between patients with unilateral (32. 1+/-18.9, n=36) or bilateral (31.7+/-20.9, n=27) disease, or between sub-groups with RAS <60% (28.3+/-13.9, n=15), unilateral RAS >60% (38.9+/-24.6, n=12), bilateral RAS >60% (36.3+/-20.4, n=6) or unilateral RAO (30.3+/-17.7, n=28), and mean average renal size similarly did not differ between the sub-groups. No correlation existed between residual patency and creatinine clearance (r=0.015); mean+/-SD renal function was almost identical in the four patency sub-groups, and average renal size mirrored this pattern. Mean 24-h urinary protein excretion was similar for the four groups, but patients with minimal ARVD had significantly less comorbid vascular disease. CONCLUSIONS: These findings suggest that the severity of proximal renal artery lesions is often unrelated to the severity of renal dysfunction in patients with ARVD. Associated renal parenchymal damage is the more probable arbiter of renal dysfunction, and this should be considered when revascularization procedures are contemplated.

Risk of morbidity from renovascular disease in elderly patients with congestive cardiac failure.

BACKGROUND: Renovasular disease commonly affects elderly people. Elderly patients with heart failure are routinely treated with angiotensin-converting-enzyme (ACE) inhibitors, which may increase risk of renal dysfunction. We investigated the frequency of renovascular disease among elderly people with heart failure. METHODS: From the local population of Salford, UK, we recruited 86 patients with heart failure with a mean age of 77.5 (SD 5.6) years, who were admitted as acute emergencies or who attended general medical clinics. We selected patients by intention to treat with ACE inhibitors. We used captopril renography to screen for renovascular disease. All patients with abnormal renograms underwent magnetic-resonance angiography of the renal arteries as well as 40% of patients with normal renograms as negative controls. FINDINGS: Magnetic-resonance angiography showed severe renovascular disease (>50% renal-artery stenosis or occlusion) in 29 (34%) patients. Captopril renography had an estimated sensitivity of 78.8% (95% CI 72.7-97.8) and specificity of 94.3% (67.6-97.3) for detection of renovascular disease. The estimated positive predictive value of captopril renography was 89.7% and the negative predictive value was 87.5%. Patients with renovascular disease had worse renal function (mean creatinine 201 [SD 56] vs 136 [40] pmol/L, p<0.001), were older (mean age 80.7 [5.6] vs 76.8 [5.3] years, p<0.01), and were more likely than patients without renovascular disease to have peripheral arterial disease. INTERPRETATION: Some elderly patients with occult renovascular disease on ACE inhibitors will be at risk of developing uraemia. Renal function should be closely monitored to detect any deterioration early.

The relevance of parity to ureteric dilatation.

OBJECTIVE: To assess whether the mild dilatation of the right ureter in women that is sometimes seen on intravenous urography (IVU) represents persistent dilatation after a previous pregnancy. PATIENTS AND METHODS: The intravenous urograms of 71 men, 63 parous and 27 nulliparous women were evaluated prospectively. The two groups of women were divided into those with and without a confirmed history of urinary tract infection (UTI) as the indication for IVU. producing five groups in all. Measurements were taken on both the 5-min and the compressed or release films on each side. RESULTS: There were no significant differences in ureteric diameters among the five groups for the uncompressed right ureter (P=0.23), the left ureter uncompressed (P=0.32) or compressed (P=0.87). For the compressed right ureter, the difference was significant, with the diameters in the parous women with proven UTIs being larger than in the other groups (P=0.043). CONCLUSION: There is a significant increase in the diameter of the compressed right ureter in the group of parous women with a history of proven UTI. Infection or parity alone do not produce this effect: the combination of the two factors is required.

Transvaginal leak of peritoneal dialysate demonstrated by CT peritoneography.

CT peritoneography is the investigation of choice for suspected leaks or hernias in patients on continuous ambulatory peritoneal dialysis (CAPD). We report a case of transvaginal leak of peritoneal dialysate in a young woman, confirmed by CT peritoneography. CAPD has been successfully recommenced following the repair of a left vaginal vault erosion.

A prospective evaluation of central venous blood flow using Doppler ultrasound in patients with a long-term central venous catheter.

Using Doppler ultrasound, we prospectively evaluated the relationship between central venous blood flow and the development of central venous thrombosis in ten patients with a long term central line. The presence of turbulent blood flow around the catheter was followed by the development of central venous thrombosis in two patients but neither had subsequent clinical sequelae. More surprisingly, however, normal blood flow was demonstrated in eight patients, two of whom subsequently developed intravascular thrombi.

Evaluation of gastric antral motor performance in patients with dysmotility-like dyspepsia using real-time high-resolution ultrasound.

Although manometric antral hypomotility and delayed gastric emptying have been reported separately in patients with dyspepsia, relationships between symptoms, antral contractility and emptying rate have not been sought. The present study therefore aimed to evaluate, simultaneously, gastric antral excursion characteristics and emptying in a sub-group of patients with severe functional dyspepsia using high-resolution real-time ultrasound. The circumference of the relaxed and contracted antrum was measured at 15-min intervals after ingestion of a 360 mL mixed nutrient meal in 36 chronic dyspepsia patients with symptoms of post-prandial bloating and epigastric distension, and in 25 healthy volunteers. Antral emptying (measured as the rate of decrease in circumference of the relaxed antrum) was slower in patients than normals (P = 0.02). In both groups, the average values for antral excursion were similar but the range of excursion in patients was significantly wider than in controls (F < 0.001), with 11 patients showing values above, and 8 showing values below the normal range. There was no relationship between antral emptying and antral excursion in either patients or volunteers. In conclusion, patients with severe functional dyspepsia show a wide range of antral performance characteristics, suggesting not only that the mechanisms responsible for the control of antral motor function are disturbed but also that the cause of the symptoms and the disturbed antral motor function are probably not directly related.

Macronodular congenital adrenal hyperplasia in an adult with female pseudohermaphroditism.

We report a case of previously undiagnosed congenital adrenal hyperplasia presenting with virilisation in a 59-year-old woman. Biochemical analysis revealed C-21 hydroxylase deficiency. CT demonstrated adrenal hyperplasia and a 3.8-cm adrenal nodule, raising the possibility of the development of an autonomous adrenal adenoma or carcinoma. The adrenal nodule regressed significantly with oral replacement steroid therapy over the next 30 months, indicating it to be an ACTH-dependent hyperplastic nodule and thus avoiding the need for biopsy or surgical excision. Macronodular adrenal hyperplasia should be considered in the differential diagnosis of a patient presenting with virilisation and an adrenal mass.

A prospective study of the prevalence of clear-cut endocrine disorders and polycystic ovaries in 350 patients presenting with hirsutism or androgenic alopecia.

OBJECTIVE: To determine the frequency of polycystic ovaries (PCO) on ultrasound and the incidence of clearcut endocrine disorders leading to virilization in patients complaining of hirsutism or androgenic alopecia. The major purpose was to determine a coherent policy for the routine biochemical assessment of such women. DESIGN: A prospective study of women attending a joint skin/endocrine clinic complaining of these problems. PATIENTS: Three hundred and fifty consecutive women with hirsutism and/or androgenic alopecia were assessed. MEASUREMENTS: Baseline endocrine screens were conducted on two occasions and included measurement of serum testosterone, androstenedione, dehydroepiandrosterone sulphate, sex hormone binding globulin, LH, FSH, 17-hydroxyprogesterone and PRL. The ovaries were visualized by high-resolution pelvic ultrasound scanning. RESULTS: Eight women were identified with relevant endocrine disorders; of these, one was acromegalic and one had a microprolactinoma--in both cases the association may have been fortuitous. Three had clear-cut 21-hydroxylase deficiency, one a rare hepatic enzyme deficiency (11-reductase), one a virilizing adrenal carcinoma and one a Leydig cell tumour. The latter six cases all had persistently elevated levels of serum testosterone (> 5 nmol/l). In all, 13 women had baseline testosterone levels in excess of 5 nmol/l. Polycystic ovaries were present in 81% of the cases who had erratic cycles and 52% of those with regular cycles; PCO were present in two of the women with 21-hydroxylase deficiency and in the woman with 11-oxoreductase deficiency. The Leydig cell tumour (1.2 cm diameter) was not detected on ultrasound or CT scan. CONCLUSIONS: For the exclusion of enzyme deficiencies and virilizing tumours clinical assessment and a single serum testosterone measurement will suffice.

Evaluation of human postprandial antral motor function using ultrasound.

We used high-resolution ultrasound to characterize postprandial antral excursion characteristics in 15 healthy volunteers. Antral circumference was repeatedly measured in the sagittal plane anterior to the abdominal aorta, at 15-min intervals following ingestion of a standard meal. At each recording period, the maximal and minimal antral circumference was noted. In seven volunteers, antral circumference was studied continuously for 5 min at each 15-min recording period to assess the frequency and regularity of antral excursions. Antral circumference increased immediately after meal ingestion from preprandial values of 64 +/- 2.6 (means +/- SE) to 138 +/- 3.1 mm and then gradually decreased with meal emptying to 72 +/- 2.6 mm at 90 min. The continuous recordings of antral images revealed that antral circumference transiently decreased at regular intervals; the interval between successive excursions was 20.1 +/- 0.2 s. There was no change in the excursion interval with emptying. The excursion amplitude decreased from 33 +/- 3.9 mm immediately post-meal ingestion to 13 +/- 1.5 mm at 90 min (r2 = 0.62 +/- 0.07). The ratio between the excursion amplitude and circumference of the relaxed antrum changed only slightly with time (slope = 0.0009 +/- 0.00003). Comparison of repeat studies in 10 volunteers showed a low intra-individual variation for postprandial antral circumference and excursion amplitude.