ACUTE MESENTERIC ISCHÆMIA

The experience of acute mesenteric ischæmia at St Vincent's Hospital, Melbourne, has been reviewed over 17 years. The mortality remains appallingly high. This applies particularly to those patients who had thrombosis of the superior mesenteric artery, amongst whom the mortality in this series was 97%. The mortality was slightly less in the group suffering from embolic occlusion of the superior mesenteric artery (66%), and in those suffering from thrombosis of the superior mesenteric vein (60%). A mortality of 66% was also found in patients suffering from non-occlusive gut ischæmia. Delay in diagnosis accounted for this high mortality. Early diagnosis is all-important, and this depends on the performance of mesenteric angiography in any patient suspected of having mesenteric ischæmia. Appropriate surgery may then be carried out in the occlusive group and supportive treatment, including intraarterial papaverine infusion, given to those with non-occlusive ischæmia. There is a pressing need for simple non-invasive tests to segregate those patients suffering from acute mesenteric ischæmia from those whose acute abdomen is due to some other cause.     

An Assessment of the Xenon- 133 Method of Measuring Muscle Blood Flow1

The ¹¹³Xe method for measuring muscle blood flow is discussed, and has been evaluated in both normal and ischæmic limbs, a standard amount of ischæmic exercise being employed as the stimulus to hyperæmia. This is considered to be a reliable technique with a high degree of reproducibility, which may be applied to advantage in the clinical assessment of patients with peripheral vascular disease.     

The Influence of Technical Factors upon Renal Homograft Function1

Though immunological rejection is the chief obstacle to the prolonged survival of renal homografts, a significant number of graft failures can be attributed to complications of surgical technique. The purpose of this paper is to analyse the influence of vascular anomalies in the donor kidney upon graft function. Factors considered include the duration of “warm” and “cold” ischæmia, the technical improvisation of the vascular anastomoses, and the utilization of both kidneys from any cadaver. During the past three and a half years, 43 renal homografts have been transplanted into 40 patients at the Prince Henry Hospital, Sydney. Although there has been a high incidence of vascular anomaly in this series, no donor kidney has been discarded for this reason, and satisfactory graft function has been obtained in 31 of the transplanted kidneys.     

CLAUDICATION OF THE CAUDA EQUINA

The term “claudication of the cauda equina” is examined. It has arisen from semantic errors, and a belief in ischæmia for which there is no scientific evidence. Its use tends to hamper rather than assist the investigation of patients with obscure pain in the lower limb. A preferable alternative term, “atypical sciatica”, is suggested.     

RECONSTRUCTION OF VERTEBRAL ARTERY STENOSIS1

Eight patients with transient attacks of cerebrovascular insufficiency were treated by reconstruction of an atheromatous stenosis at the origin of a vertebral artery. The technique was relatively simple and safe, and was effective in relieving symptoms. Previous reviews suggest that the symptoms of vertebrobasilar insufficiency tend to be persistent, frequent and distressing, and that they can be a prelude to brain stem infarction. The collateral circulation to the vertebrobasilar system may be restricted by anatomical variations and by disease, particularly affecting the circle of Willis. Bilateral vertebral artery disease can cause appreciable ischæmia even without associated carotid artery disease. Carotid endarterectomy is not particularly effective in relieving vertebrobasilar symptoms. Vertebral artery reconstruction appears to be the appropriate treatment for vertebrobasilar insufficiency.     

USE OF SPIRAL COMPUTERIZED TOMOGRAPHY IN LIEU OF ANGIOGRAPHY FOR PREOPERATIVE ASSESSMENT OF LIVING RENAL DONORS

PURPOSE: We evaluate whether spiral computerized tomography (CT) can be used in lieu of renal angiography for preoperative assessment of living renal donors, with special attention to multiplicity of renal vasculature. MATERIALS AND METHODS: A total of 47 living renal donor candidates were evaluated with spiral CT and all but 2 underwent donor nephrectomy. Patients were divided into early and late groups because there was a learning curve with spiral CT. In the early group 18 donors underwent renal angiography as well as spiral CT and 10 underwent nephrectomy after spiral CT only. In the late group 5 had dual radiographic evaluation for ambiguities in spiral CT interpretation and 12 underwent nephrectomy after spiral CT only. Spiral CT was performed and interpreted blind to angiographic results, and vice versa. RESULTS: Spiral CT identified 50 of 52 renal arteries (96%) found at surgery overall and 23 of 25 (92%) found at surgery after spiral CT only. Two accessory arteries were missed in the 10 early group donors evaluated with spiral CT only, yielding an early negative predictive value of 80%. Renal angiography identified another accessory artery missed by spiral CT in the early group. All 3 missed vessels were identified retrospectively. No arteries found at surgery were missed in the late group (negative predictive value 100%), although there were 2 false-positive results detected by spiral CT relative to renal angiography in 1 candidate renal unit. Overall accuracy to predict early renal artery division relative to surgical findings was 93% for spiral CT and 91% for renal angiography. However, early renal artery division was clinically significant for only 1 of 11 vessels found at surgery. Spiral CT demonstrated 4 anomalous venous returns and renal angiography identified none. However, spiral CT missed 2 accessory veins and identified only 1 of 2 fibromuscular dysplasia cases. Total cost for spiral CT and renal angiography was $886 and $2,905, respectively. CONCLUSIONS: Spiral CT is a reasonably good alternative to renal angiography for living renal donor assessment but there is a profound learning curve for performance and interpretation. Renal angiography is still the gold standard with respect to the identification of arterial multiplicity and fibromuscular dysplasia, and it should be used adjunctively in cases with spiral CT ambiguity. Neither spiral CT nor renal angiography is ideal for the assessment of early renal artery division which is seldom an issue. The benefits of spiral CT over renal angiography are potentially lower morbidity, improved donor convenience and reduced cost.     

Renal angiography and the management of severe closed renal trauma.

The purpose of this study was to determine the place of selective renal angiography in the assessment of major renal trauma. Thirty-one cases of renal injury assessed by urography and angiography were reviewed, and the radiological features correlated with the subsequent clinical course. Based on the angiographic findings, a classification of these more severe injuries is proposed, and the prognostic significance of renal ischaemia demonstrated. Because conservative treatment in those cases with significant ischaemia is likely to fail, early elective surgery is recommended. In this selected group, viable renal tissue can be preserved, and the necessity for subsequent nephrectomy due to secondary haemorrhage, or continuing urine leakage, is avoided.     

MULTIPLE PRIMARY MALIGNANCIES IN RENAL CELL CARCINOMA

Purpose

We determine the incidence and nature of multiple primary malignancies in patients with renal cell carcinoma, and whether these patients have an increased risk of a second primary malignancy.

Materials and Methods

Between July 1989 and January 1997, 551 patients underwent an operation for renal cell carcinoma. The incidence of other primary malignancies was determined and classified as antecedent, synchronous or subsequent. The observed number of subsequent malignancies after diagnosis of renal cell carcinoma was compared to the expected number based on age, race and sex specific 1990 to 1994 incidence rates from the United States Surveillance, Epidemiology and End Results data using the Poisson test.

Results

The number of primary malignancies, including cutaneous malignancies, was at least 1 in 148 patients (26.9%), at least 2 in 34 (6.2%), at least 3 in 6 (1.1%) and 4 in 1 (0.2%). Other malignancies were antecedent in 85 cases (45.0%), synchronous in 74 (39.4%) and subsequent in 30 (16.0%). The most common other primary malignancies were breast, prostate, colorectal and bladder cancer, and nonHodgkin's lymphoma. Only men with renal cell carcinoma had an increased risk of bladder cancer (standardized incidence ratio 4.3, p = 0.0067).

Conclusions

Breast, prostate, colorectal and bladder cancer as well as nonHodgkin's lymphoma were the most common other primary malignancies. Men with renal cell carcinoma have an increased risk of subsequent bladder cancer.     

A Comparison of Perfusates for 24-Hour Preservation of Ischæmically Damaged Canine Kidneys

A comparison is made of the efficacies of three solutions for brief perfusion of ischæmically damaged canine kidneys before 24 hours' preservation in ice and autotransplantation. Perfusion with a plasma-red-cell mixture, with intracellular electrolyte solution (Collins C₃), mid perfusion with an extracellular “electrolyte solution” all gave comparable results, similar to those in a control group with no perfusion.     

RENAL EFFECTS OF CARDIAC ANGIOGRAPHY WITH DIFFERENT LOW-OSMOLAR CONTRAST MEDIA

The aim of this study was to evaluate the renal effects of cardiac angiography performed with three low-osmolar contrast media (CM): iopromide (IPR), ioversol (IVR) and ioxaglate (IOX). IPR and IVR are non-ionic CM, IOX is an ionic CM. Different parameters of renal function were determined before and 6, 24, 48, 72 hrs after angiography in 45 patients: 15 patients were examined with IPR, 15 with IVR and 15 with IOX. Glomerular effects – Plasma creatinine increased slightly at the 24th hour after IVR and IOX and at 48 hours after IOP. A significant increase in plasma β2-microglobulin was observed, at the same time, only after IOX. A significant decrease in creatinine clearance was found at 6 hours after IOX. No significant variations in glomerular filtration rate (GFR) and in effective renal plasma flow were found at 48 hours after cardiac angiography; while filtration fraction was significantly reduced after IOP and IOX. Tubular effects – A marked decrease in sodium clearance and a relevant increase of urinary activities of different tubular enzymes were found after cardiac angiography with all CM, but were more evident after the ionic CM IOX, than after the two non-ionic agents. These tubular effects reached the maximum between 6 and 24 hours and returned to baseline within 72 hrs after cardiac angiography. In conclusion, slight glomerular effects were observed mainly after IOX. A reversible tubular malfunction was found with the three low-osmolar CM and was more evident after ionic CM IOX, thus suggesting that other mechanisms, besides osmolarity, play a role in tubular toxicity due to CM. In no patient did the glomerular and tubular effects of CM have a clinical relevance.     

THE ROLE OF BRADYKININ IN ENDOTOXIC SHOCK OF INTESTINAL ORIGIN

A relationship was looked for between blood levels of bradykinin and endotoxæmia produced by superior mesenteric artery occlusion in the rabbit. The levels of bradykinin were unrelated to and unaltered by the degree of endotoxæmia observed in the systemic and portal circulations. These findings suggest that bradykinin is not responsible for the release of endotoxin from the gut, or for the circulatory collapse which follows.     

THE CREATION OF ARTIFICIAL SUBCUTANEOUS ARTERIOVENOUS FISTULAS IN PATIENTS WITH MALIGNANT HEMATOLOGICAL DISEASE

Creation of an artificial subcutaneous arteriovenous fistula was attempted in five patients with malignant hæmatological disorders (two with Hodgkin's disease, two with acute lymphatic leukæmia, and one with acute myeloid leukæmia). The average time from the start of treatment to attempted creation of the fistulæ was four years. Neither direct arteriovenous anastomosis nor an interposition mandril graft was successful in any patient. Failure was attributed to impaired venous run-off secondary to previous episodes of thrombophlebitis induced by the intravenous administration of cytotoxic drugs. The use of an arteriovenous fistula early in the course of the disease might minimize these later problems.     

Bilateral renal artery aneurysm rupture in a man with leukemia: report of a case

Renal artery aneurysms, once thought to be rare, are diagnosed more frequently due to the increasing use of computed tomography, angiography, and other imaging to delineate pathology. The incidence is less than 1% in the general population,(1,2) and increases to 2.5% in the hypertensive population undergoing angiography.(3) Incidence approaches 10% in autopsy series.(4) Despite increasing incidence, renal artery aneurysm rupture remains uncommon. We report the case of a man with chronic myelomonocytic leukemia who suffered bilateral renal artery aneurysm rupture over the course of 1 month.     

RENAL MEDULLARY CARCINOMA

Purpose

Renal medullary carcinoma is a rare and extremely aggressive neoplasm that almost always develops in young patients with sickle cell trait. To our knowledge all cases to date have been metastatic at surgical resection. Pathological examination reveals an aggressive tumor mainly involving the renal medulla with a varied morphology. The prognosis is dismal. Mean survival from the time of resection is 15 weeks (range 2 to 52). The disease course has not been altered by surgery, radiotherapy or various regimens of chemotherapeutic agents.

Materials and Methods

We add to the literature our experience treating renal medullary carcinoma in 2 cases and review the existing literature on this disease.

Results

Both patients whom we treated died of the disease, as have the other 35 patients described in the literature.

Conclusions

A high index of suspicion may lead to earlier diagnosis and treatment, and survival of patients with renal medullary carcinoma.     

RENAL ANGIOMYOLIPOMA IN CHILDREN: DIAGNOSTIC DIFFICULTY IN 3 PATIENTS

Purpose

Because angiomyolipoma is less common in children than in adults, its diagnosis can be difficult. We present 3 cases of pediatric angiomyolipoma in which diagnostic problems resulted due to the presenting characteristics.

Materials and Methods

We report on 3 children with unilateral renal angiomyolipoma. Computerized tomography (CT) and ultrasonography revealed 3 large renal masses, 20, 7 and 8 cm. in diameter, respectively. A correct diagnosis was not made preoperatively in any case by CT, ultrasound or fine needle biopsy. Wilms tumor was suspected in the first patient who received preoperative chemotherapy. Imaging was inconclusive in the other 2 cases.

Results

All patients underwent surgical exploration and subsequent nephrectomy due to the large size of the tumor. At followup 33, 23 and 13 months postoperatively all children were well without signs of recurrence.

Conclusions

It has been reported that the demonstration of fat on renal ultrasound and CT can diagnose angiomyolipoma in 95% of the cases. Most radiologists rely solely on CT demonstration of lipid density in the renal mass to diagnose angiomyolipoma but the identification at imaging of lipid tissue may be difficult in small tumors. In our cases the fat content of the tumors was less than 10% despite the large size. This low fat content results in misdiagnosis, since fatty tissue is also present in other renal tumors, such as lipoma, liposarcoma, teratoma and Wilms tumors. We recommend conservative surgery when tumor size permits in pediatric patients with angiomyolipoma to avoid chemotherapy.     

Mycotic Aneurysms of the Aortic Root1

The clinical details of six patients presenting with mycotic aneurysms as complications of aortic valve endocarditis are presented. A distinction is made between this little-described condition and congenital sinuces and fistulæ. The lesion was demonstrated in all of the patients by cineangiography, and this investigation is strongly recommended. The mortality in the series was high, due to a combination of preoperative toxæmia and resistant heart failure. It is suggested that early investigation of patients presenting with unresponsive aortic endocarditis may reduce the mortality of surgery and will commonly demonstrate the presence of sinuses and fistulæ, facilitating both the planning and performance of the operation.     

RENAL ABSCESS IN CHILDHOOD*

Eight patients with renal abscess were seen in a 15-year period. The patients' ages ranged from 3 to 15 years with a mean of 6.5 years. Included were 7 female children, five of whom were Aboriginal, and 1 male child. Clinical presentation ranged from localized renal symptoms to a genet alized septicaemic illness. Ultrasonography proved to be the most useful diagnostic investigation. Surgical management consisted of open surgical drainage in 5 cases with secondary nephrectomy in one. Two recent cases were managed by percutaneous drainage of the abscess together with appropriate antibiotic therapy. One case was successfully managed by antibiotic therapy without surgical or radiological intervention. In 5 cases the infecting organism was penicillinase-producing Staphylococcus aureus and, in 2 cases, Escherichia coli was isolated. It is concluded that the diagnosis of renal abscess should be considered in patients with a febrile septicaemic illness, particularly in Aboriginal female children. Ultrasonography is recommended as the investigation of choice which can also be used to establish percutaneous drainage, thus avoiding surgery.     

THE DIAGNOSIS AND LOCAL STAGING OF RENAL CANCER — AN APPRAISAL

The standard pattern of investigation for renal masses usually involves excretion urography, ultrasonography and angiography. This study was undertaken to determine whether computed tomography (CT) and fine needle aspiration cytology could provide information that might allow this pattern to be modified. Diagnostic information was obtained by needle aspiration cytology in 25 patients who were shown at operation to have a neoplasm. The diagnosis was correct in 22 cases (88%). By comparison, arteriography was accurate in 22 out of 24 (92%), and computed tomography provided the correct diagnosis in 19 out of 21 (90%). Staging was performed surgically and histologically in 21 patients, and when this was compared with the results of CT staging there was complete agreement in 13 cases (62%). A literature review revealed an average staging accuracy for CT of 81% while arteriography was accurate in only 57%. Thus CT appears to be as good as arteriography for diagnosis and potentially better for local staging. It is also less invasive, rapid and cost effective and could supersede arteriography as the primary diagnostic and staging investigation in patients with a solid renal mass.     

Protracted anuria due to active vasoconstriction in primary or secondary malignant hypertension

Anuria complicated the malignant phase of hypertension in twelve patients (ten males and two females). Five were black; five had primary hypertension; one had HBs virus angiitis; the six remaining cases suffered from previously documented renal disease, including two with Berger's disease. Renal angiography showed interruption of renal blood flow as far as the main branches of the renal artery and/or a false impression of 'cortical necrosis' and of 'renal infarcts'. In contrast, renal biopsy did not show irreversible vascular damage. Thus, anuria was mainly functional and due to active renal vasoconstriction. This was confirmed by the subsequent course; diuresis resumed after 1 week to 24 months of dialysis. Repeat angiography in six cases showed recovery of renal circulation and disappearance of 'cortical infarcts', even when plasma renin activity remained elevated and hypertension was not controlled. In one case captopril induced a new reversible episode of anuria. These observations suggest that active vasoconstriction with prolonged anuria might be due to some vasoconstrictive substance other than angiotensin II.     

CONSERVATIVE MANAGEMENT OF NON-TRAUMATIC SUBCAPSULAR RENAL HEMATOMA: A CASE REPORT

The case of a 78-year-old woman with a non-traumatic subcapsular renal hematoma is described. She complained of right flank pain and fever and the findings following abdominal echography, computerized tomography (CT) scan and renal angiography agreed with a diagnosis of subcapsular renal hematoma without renal tumor. Percutaneous drainage of the hematoma improved her clinical symptoms and the lesion as seen on CT scan. Ten months later, no change in the right kidney could be seen on CT scan and echography. We conclude that conservative management is the first choice for subcapsular renal hematoma without a definite etiology, especially in an elderly patient.