PubMed Health⌕ Search

Biomedical subjects

P A Kalra

Publications and source records attributed to P A Kalra.

At least 19 recordsLinked to original sources

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.

Aged↗

Prevalence of hypogonadism in male patients with renal failure.

BACKGROUND: Hypogonadism in men may be secondary to renal failure and is well recognised in patients with end-stage renal disease. It is thought to contribute to the sexual dysfunction and osteoporosis experienced by these patients. However, the association between hypogonadism and lesser degrees of renal dysfunction is not well characterised. METHODS: The gonadal status of 214 male patients (mean age 56 (SD 18) years) attending a renal centre was studied; 62 of them were receiving haemodialysis and 22 continuous ambulatory peritoneal dialysis for end-stage renal disease, whereas 34 patients had functioning renal transplants and 96 patients were in the low-clearance phase. Non-fasting plasma was analysed for testosterone, follicle-stimulating hormone, luteinising hormone, sex hormone-binding globulin, parathyroid hormone and haemoglobin. Creatinine clearance was estimated in patients not on dialysis, and Kt/V and urea reduction ratio were assessed in patients on dialysis. Testosterone concentrations were classified as normal (>14 nmol/l), low-normal (10-14 nmol/l) or low (<10 nmol/l). RESULTS: 56 (26.2%) patients had significantly low testosterone levels and another 65 (30.3%) had low-normal levels. No significant changes were seen in sex hormone-binding globulin or gonadotrophin levels. Gonadal status was not correlated with haemoglobin level, parathyroid hormone level, creatinine clearance, or dialysis duration or adequacy. CONCLUSION: Over half of patients with renal failure, even in the pre-dialysis phase, have low or low-normal levels of testosterone, which may be a potentially reversible risk factor for osteoporosis and sexual dysfunction. These patients may be candidates for testosterone-replacement therapy, which has been shown to improve bone mineral-density and libido in men with low and low-normal testosterone levels.

Adolescent↗

Severe acute renal failure in adults: place of care, incidence and outcomes.

BACKGROUND: Department of Health guidelines recommend specialist critical care facilities for patients with severe single-organ failure such as acute renal failure (ARF). Prospective studies examining incidence, causes and outcomes of ARF outside of intensive care settings are lacking. AIM: To determine the incidence, causes, place of care and outcomes of severe single-organ ARF. DESIGN: Prospective observational study. METHODS: For 6 weeks in June-July 2003, renal physicians were contacted daily, and ICUs on alternate days, to identify cases of severe single-organ ARF in the Greater Manchester area. All patients with serum creatinine >or=500 micromol/l and not requiring other organ support were included. Patients with end-stage renal disease were excluded. Survivors were followed up at 90 days and 1 year from admission. Two independent consultant nephrologists assessed each case using anonymized summaries. RESULTS: Eighty-five patients had multi-organ ARF and 28 had severe single-organ ARF (380 and 125 pmp/year, respectively). Of those with single-organ ARF, 10 (36%) had known pre-existing chronic kidney disease. Renal replacement therapy (RRT) was required in 15 (54%). Total bed occupancy on ICUs relating to single-organ ARF was 59 days (range per patient 1-21). At 90 days, 18 (64%) were alive, and 17 (94%) had independent renal function. At 1 year, 4/18 had died, none receiving RRT at the time of death. Survivors all had independent renal function. In 13 (46%) cases there was an unacceptable delay in patient transfer and in 7 (25%), delays in assessment or commencement of RRT may have adversely affected patient outcome. DISCUSSION: The incidence of ARF treated with RRT is rising. Delays in transfer to renal services may result in inappropriate ICU bed use, and may adversely affect patient outcomes. There are serious problems regarding the appropriate use of expensive and limited medical resources in the critical care area, and in providing safe and effective treatment of patients with ARF.

Acute Kidney Injury↗

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.

Arteriosclerosis↗

Early management and prevention of acute renal failure.

Despite major advances in nutritional support, membrane technology and dialytic techniques, the mortality of patients with acute renal failure (ARF) who require dialysis is still almost 50% (1). Increased patient age and co-morbidity confer a poorer prognosis, and the condition is certainly commoner in this patient group. Hence, one study showed that the age-related annual incidence of ARF increased from 17 per million in adults under 50 years to 949 per million in the 80-89 age group (2). Over 60% of cases of ARF ultimately result from renal hypoperfusion and consequent intra-renal ischaemic damage, which leads to acute tubular necrosis (ATN) (3). Ischaemic ARF may thus result from a diversity of systemic and intra-renal circulatory stresses including acute losses of blood and extra-cellular fluids, from low cardiac output states such as following ischaemic or toxic myocardial damage, and even from drug-induced renal perfusion shutdown (ACE inhibitors, non-steroidal anti-inflammatory agents). Many cases of ARF have a multi-factorial aetiology (e.g. post-surgical sepsis with hypovolaemia, hypotension and injudicious antibiotic use), and these patients, who often have other organ failure, fit into the poorer prognostic category. A large number of patients with ischaemic ARF pass through a phase of potentially reversible pre-renal oliguria; early recognition and prompt, appropriate treatment of these pre-renal factors can prevent progression to established ARF, with the genuine prospect of improved patient morbidity and mortality, and this is the main scope of this article. Early diagnosis in other patients with ARF, such as those with acute inflammatory renal disease (e.g. vasculitis) or urinary tract obstruction, will allow appropriate prompt treatment and the possibility for reversal of the ARF. The following account, which is composed of personal experience, that of colleagues, and the literature (1,4), is not intended to provide a comprehensive guide to the management of ARF, but seeks to highlight important common pitfalls and fundamental principles in the recognition and subsequent preventive treatment of these patients.

Acute Kidney Injury↗

Carbamazepine-induced acute granulomatous interstitial nephritis.

A 79-year-old man, newly started on carbamazepine, presented with rash, eosinophilia and liver dysfunction progressing to acute renal failure despite discontinuation of the anti-epileptic agent. Percutaneous renal biopsy revealed acute granulomatous interstitial nephritis, which responded successfully to high-dose oral steroid therapy.

Acute Disease↗

Clinicopathological correlation in biopsy-proven atherosclerotic nephropathy: implications for renal functional outcome in atherosclerotic renovascular disease.

BACKGROUND: Atherosclerotic renovascular disease (ARVD) is commonly associated with renal failure. It is now recognized that intrarenal damage, (ischaemic or atherosclerotic nephropathy) is a major contributor to the renal impairment in these patients. In this study the impact of histological changes upon renal functional outcome was investigated in patients with atherosclerotic nephropathy. METHODS: The Hope Hospital renal biopsy database (1985-1998) was interrogated for patients with histology compatible with atherosclerotic nephropathy. Case-note review enabled the assessment of several clinical parameters and outcomes, including change in creatinine clearance per year (DeltaCrCl (ml/min/year)), blood pressure control, dialysis need, and death. Renal parenchymal damage was analysed by morphometric analysis (of interstitial fibrosis and glomerulosclerosis) and a semi-quantitative chronic damage score (score 0-3 (normal-severe) for each of glomerulosclerosis, interstitial fibrosis, tubular atrophy, and arteriolar hyalinosis; maximum=12). Patients were stratified into two groups who had either deteriorating (group 1) or stable (group 2) renal function during follow-up. RESULTS: Twenty-five patients (age 64.7+/-10.5, range 43-83 years; 17 male, eight female) were identified. Sixteen patients had undergone angiography; two had significant (>50%) renal artery stenosis. Mean follow-up was 25.6+/-14.8 (range 5-50) months. Group 1 patients had DeltaCrCl -7.4+/-6.8 ml/min/year, n=14 and group 2 patients had DeltaCrCl 4.8+/-7.0 ml/min/year, n=11. Four patients in group 1 developed end-stage renal disease and five patients died (three in group 1 and two in group 2). At study entry, group 1 patients had worse renal function (CrCl 27.6+/-17.6 vs 36.0+/-33.9, NS), greater proteinuria (1.2 vs 0.5 g/24 h, NS), and higher systolic blood pressure (167.1+/-30.8 mmHg vs 150.6+/-37.8, NS) compared with group 2 patients. Group 1 patients showed more glomerulosclerosis (51.6 vs 24.9%, P:<0.01), greater proportional interstitial volume (44.9 vs 33.9%, P:<0.02), and higher overall chronic damage score (P:<0.05) than those in group 2. There was a significant correlation between renal functional outcome and chronic damage score, glomerulosclerosis and proportional interstitial volume for the entire patient cohort. CONCLUSION: In patients with atherosclerotic nephropathy the severity of histopathological damage is an important determinant and predictor of renal functional outcome.

Adult↗

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%.

Adult↗

Isolated sarcoid granulomatous interstitial nephritis: review of five cases at one center.

AIMS: To identify any clinical or biochemical parameters which determine prognostic outcome in isolated sarcoid granulomatous interstitial nephritis presenting with renal failure. METHODS: A review of five cases of renal failure due to isolated sarcoid granulomatous interstitial nephritis, which presented to Hope Hospital over the 7-year period 1994 to 2000. Follow-up averaged 35 months with a range of 11 to 73 months. RESULTS: Only one patient had an elevated serum ACE at presentation, reflecting the suboptimal sensitivity of this test as a marker in sarcoidosis and the limited extent of disease in these patients. Four of the five cases had a marked improvement in creatinine clearance within 10 days of starting oral prednisolone. Two patients required acute hemodialysis on presentation. Their renal failure responded to treatment with steroids, enabling withdrawal of dialysis within 10 days. All patients remained dialysis-independent although serum creatinine levels rose during follow-up. One patient experienced a relapse that responded to an increased dose of steroid. CONCLUSIONS: Serum ACE is not reliable in the diagnosis of renal failure due to sarcoid interstitial nephritis and the diagnosis can only be made on renal biopsy. First-line treatment with oral prednisolone results in a rapid improvement in creatinine clearance although prolonged treatment may be needed to prevent a relapse.

Aged↗

New insights into the epidemiologic and clinical manifestations of atherosclerotic renovascular disease.

Atherosclerotic renovascular disease (ARVD) continues to challenge the clinician as we enter the third millenium. ARVD frequently complicates patients with other vascular pathological states, and it is an increasingly common cause of end-stage renal failure. Although renovascular interventional procedures are now widely available and are of benefit to some patients with ARVD, a large proportion still progress to dialysis. Recent epidemiological investigations have emphasized the relationship between ARVD and other vascular diseases, and these are notable in patients with coronary artery disease and/or cardiac failure. Increased awareness of the possible coexistence of ARVD in patients with these latter conditions may allow earlier diagnosis and a minimization of complications (eg, angiotensin-converting enzyme inhibitor-related uremia or flash pulmonary edema). Contemporary studies also highlight the importance of intrarenal vascular and parenchymal injury in the cause of chronic renal failure in many patients with ARVD. Severe renal structural damage often coexists with proximal renal arterial narrowing, and this can explain the variability of renal functional outcomes known to accompany revascularization procedures. More appropriate selection of those patients likely to benefit from renovascular revascularization is now required. Large-scale trials that will identify the optimal approach to improving renal functional and survival outcomes in this high-risk group of patients are now long overdue.

Arteriosclerosis↗

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.

Aged↗

Changes in lipid profiles in non diabetic, non nephrotic patients commencing continuous ambulatory peritoneal dialysis.

This study examined the effect on patient lipid profile of commencing continuous ambulatory peritoneal dialysis (CAPD). We followed eighteen non diabetic, non nephrotic patients for 9 months before and after dialysis commencement and compared lipid profiles. Mean cholesterol levels rose from 4.98 mmol/L to 5.42 mmol/L (p < 0.05). This change was chiefly due to a rise in low density lipoprotein (LDL) cholesterol. The LDL cholesterol rose after dialysis commencement and continued to rise up to 9 months later. High-density lipoprotein (HDL) cholesterol remained stable. Serum albumin and body weight fell during follow-up, suggesting that the rise in cholesterol was not a reflection of enhanced nutritional status. This study highlights the pro-atherogenic change in lipids that results from commencing CAPD. This phenomenon is not seen in hemodialysis, and it should be considered when selecting a dialysis modality, given the increased risk of cardiovascular disease in the dialysis population.

Cholesterol↗

Questionnaire study and audit of use of angiotensin converting enzyme inhibitor and monitoring in general practice: the need for guidelines to prevent renal failure.

OBJECTIVES: To determine the current pattern of use of angiotensin converting enzyme inhibitor and monitoring of renal function in general practice and to audit all admissions to a regional renal unit for uraemia related to use of these drugs. DESIGN: Postal questionnaire sent to 400 general practitioners; audit of clinical notes of all patients receiving these drugs in one large general practice; audit of all cases of uraemia (creatinine concentration >500 micromol/l) related to treatment presenting to hospital renal services over 12 months. SETTING: General practices in the North Wales health authority and one in central Manchester. Regional renal unit in Salford. MAIN OUTCOME MEASURES: Proportion of general practitioners who regularly monitored renal function before and after initiation of angiotensin converting enzyme inhibitors. Indications for treatment and details of monitoring of renal function in patients receiving these drugs. Incidence of related uraemia and evidence of comorbid disease, other aetiological factors, delayed detection, and patient outcome. RESULTS: 277 (69%) general practitioners replied; 235 (85%) checked renal function before but only 93 (34%) after the start of treatment, and 42 (15%) never checked renal function. Angiotensin converting enzyme inhibitors were prescribed for 162 patients from a total of 3625 aged >35 years (mean age 66.4 (SD 15.9) years). Monitoring of renal function occurred before treatment in 55 (45%) and after start of treatment in 35 (29%) of the 122 patients treated in general practice. Angiotensin converting enzyme inhibitors could be causally implicated in 9 (7%) of 135 admissions for uraemia (mean age 74.2 (7. 2) v 62.1 (2.1) years; P<0.01). 3 patients had renovascular disease and 6 had congestive cardiac failure with another intercurrent illness. Renal function had not been checked in any patient after the start of treatment; mean duration of illness before admission was 10.5 (3.2) days. Mean length of hospital stay was 20.9 (10.4) days; there were 8 survivors. CONCLUSION: Cases of uraemia related to treatment with angiotensin converting enzyme inhibitors are still encountered and are often detected late because of lack of judicious monitoring of renal function in vulnerable, often elderly, patients, especially at times of intercurrent illness. Guidelines for appropriate monitoring of renal function may help to minimise the problem.

Acute Kidney Injury↗

Proteinuria in atherosclerotic renovascular disease.

Proteinuria is well described in atherosclerotic renovascular disease (ARVD), but the prevalence is unknown, and the pathogenesis may vary between patients. Substantial proteinuria (> 2 g/day) however, would be regarded by many as atypical of ARVD. We studied 94 patients (52 male) with ARVD, median age 67 years (range 49-87). Digital subtraction angiography was performed on all patients. Protein was assayed in 24-h urine samples and GFR derived using the Cockroft-Gault formula. Forty-nine patients (52%) had proteinuria < 0.5 g/24 h. Proteinuria increased with worsening renal function. Biopsies from seven non-diabetic patients with substantial proteinuria showed: minimal changes (1); glomerular sclerosis with marked ischaemic changes (3); focal glomerulosclerosis (2); and athero-emboli (1). Proteinuria, rather than being indicative of other pathology, is often a marker of severity of parenchymal disorder in atherosclerotic nephropathy, which itself is the major determinant of renal dysfunction in patients with ARVD.

Aged↗