Renal biopsy findings among Indigenous Australians: a nationwide review.

Australia's Indigenous people have high rates of chronic kidney disease and kidney failure. To define renal disease among these people, we reviewed 643 renal biopsies on Indigenous people across Australia, and compared them with 249 biopsies of non-Indigenous patients. The intent was to reach a consensus on pathological findings and terminology, quantify glomerular size, and establish and compare regional biopsy profiles. The relative population-adjusted biopsy frequencies were 16.9, 6.6, and 1, respectively, for Aboriginal people living remotely/very remotely, for Torres Strait Islander people, and for non-remote-living Aboriginal people. Indigenous people more often had heavy proteinuria and renal failure at biopsy. No single condition defined the Indigenous biopsies and, where biopsy rates were high, all common conditions were in absolute excess. Indigenous people were more often diabetic than non-Indigenous people, but diabetic changes were still present in fewer than half their biopsies. Their biopsies also had higher rates of segmental sclerosis, post-infectious glomerulonephritis, and mixed morphologies. Among the great excess of biopsies in remote/very remote Aborigines, females predominated, with younger age at biopsy and larger mean glomerular volumes. Glomerulomegaly characterized biopsies with mesangiopathic changes only, with IgA deposition, or with diabetic change, and with focal segmental glomerulosclerosis (FSGS). This review reveals great variations in biopsy rates and findings among Indigenous Australians, and findings refute the prevailing dogma that most indigenous renal disease is due to diabetes. Glomerulomegaly in remote/very remote Aboriginal people is probably due to nephron deficiency, in part related to low birth weight, and probably contributes to the increased susceptibility to kidney disease and the predisposition to FSGS.

Prevalence of proteinuria in rural adult population in Tamil Nadu.

BACKGROUND & OBJECTIVES: Presence of proteinuria is considered as an early marker of an increased risk of progressive kidney disease. Angiotensin converting enzyme (ACE) inhibitors (ACEi) and angiotensin II receptor blockers (ARB) treatment to persons with proteinuria and chronic kidney disease has been shown to decrease the progression to endstage renal disease. As the exact prevalence of proteinuria is not known in the general population, we undertook this study to estimate the same in a rural adult population in Vellore district, Tamil Nadu. METHODS: A convenient sample of 5,043 adults was included. All individuals were tested for albuminuria by albumin dipstick examination in an untimed urine sample. Individuals who tested positive for albuminuria underwent a second dipstick examination after a gap of one week. Individuals with persistent albuminuria on the second dipstick examination underwent further evaluation which included medical history, physical examination, 24 h urine protein estimation, total serum protein and albumin estimation. Ultrasound of the abdomen was done in patients with renal failure and renal biopsy was performed in selected patients. RESULTS: Of the total 5,043 individuals screened, 63.1 per cent were females. Mean age of the study population was 50.94 +/- 11.2 yr. First dipstick test identified 594 individuals positive for albuminuria. Repeat dipstick could be done in only 576, of whom 212 showed persistent albuminuria. Significant proteinuria was detected in 24 individuals of the 208 who had 24 h urine protein measured. Of these 24 patients, 3 were found to have chronic renal failure, 12 were presumed to have diabetic nephropathy clinically, one each had focal segmental glomerulosclerosis and biopsy proven diabetic nephropathy, and 7 patients had proteinuria of unknown aetiology. INTERPRETATION & CONCLUSION: The prevalence of proteinuria in this adult rural population was 0.47 per cent (0.30-0.67%). The detection and treatment of chronic kidney disease in 24 individuals is bound to reduce the rate of decline of renal functions. Screening programme for proteinuria in different parts of country may be an effective measure to bring a decline in rate of progression of chronic kidney disease in general population.

Characterization of kidney lesions in Indian adults: towards a renal biopsy registry.

BACKGROUND: In the absence of a renal biopsy registry, there is a paucity of data on the renal disease pattern seen in India. This study reviews the changing pattern of renal disease seen at a single center over the last 30 yrs. METHODS: Histopathological data of 5415 adequate native kidney biopsies performed on consecutive adult Indian patients presenting to our hospital from 1986-2002 were analyzed. This pathological demography classified according to the modified World Health Organization (WHO) classification was compared to the earlier published cohort collected from 1971-1985 (n=2827) to ascertain the changing trends. RESULTS: The indications for renal biopsy were comparable between the cohorts and included nephrotic syndrome (65%), nephritic syndrome (13%) and chronic renal failure (10.2%). Primary glomerular disease accounted for 71% of all biopsies. Non-immunoglobulin A (IgA) mesangio proliferative glomerulonephritis as a group was the predominant pathology (20.2%), followed by idiopathic focal segmental glomerulosclerosis (FSGS) (17%), minimal change disease (MCD) (11.6%), membranous glomerulopathy (MN) (9.8%), IgA nephropathy (8.6%) and membranoproliferative glomerulonephritis (MPGN) (3.7%). Of the patients with secondary kidney diseases, lupus nephritis (6.5%), diabetic nephropathy (2.5%), interstitial nephropathy (2.5%) and benign nephrosclerosis (2.2%) were notable. During the 31 yrs of the study period, there was a steady increase in FSGS prevalence (p<0.001), MN (p<0.0001), and post infectious glomerulonephritis (PIGN) (p<0.001). A reduction in the frequency of MPGN (p<0.001) and MCD (p<0.001) was observed. CONCLUSIONS: This is the largest series of renal biopsy data from India; and therefore, could reflect the demographic picture of renal diseases in this country. It discusses evolving patterns over 30 yrs and highlights differences with the developed world. This report represents the basis for the future of a renal biopsy registry in India.

Osmotic nephropathy resulting from maltose-based intravenous immunoglobulin therapy.

Intravenous immunoglobulin preparations are being used for an increasing number of indications. To minimize adverse reactions, sugar additives such as sucrose, maltose, and glycine are added to some preparations to serve as stabilizing agents. Intravenous immunoglobulin infusion induces acute renal failure (ARF) via a mechanism of osmotic nephrosis. Most reported cases are related to the use of sucrose-based intravenous immunoglobulin. Herein, we describe a patient with lupus nephritis treated with an immunoglobulin preparation containing maltose who developed ARF with histologic changes characterized by vacuolization and swelling of renal proximal tubular cells. Our case draws nephrologists' attention to the potential of maltose-based immunoglobulin in producing renal failure. Awareness and exercising caution in high-risk groups is elementary to the prevention of this condition.

Presentation, prognosis and outcome of IgA nephropathy in Indian adults.

BACKGROUND: IgA nephropathy (IgAN) is not well characterized in India. This retrospective study of 478 patients with IgAN was performed to clarify the presenting features, prognostic factors and the renal survival rates of the disease. METHODS: Three hundred and forty-seven patients who had been followed on average for 27 months after diagnosis were divided into two groups based on renal function at diagnosis. In group 1 (229 patients), the creatinine clearance estimated by the Modification of Diet in Renal Disease formula was <85 mL/min and in group 2 (118 patients) it was >/=85 mL/min. RESULTS: The predominant modes of presentation were nephrotic syndrome, hypertension and renal failure. Twenty-nine percent of patients had more than a 20% decline in renal function at the last follow up. Multivariate analyses with stepwise logistic regression identified hypertension (odds ratio (OR) 3.5), nephrotic range proteinuria (OR 3.4) and sclerosed glomeruli on biopsy (OR 4.1) to be independently associated with progression in group 1 and hypertension (OR 2.3) in group 2. Seventeen percent of patients progressed to end-stage renal disease (ESRD). Using multivariate analysis by the Cox model, four risk factors for developing ESRD were identified: hypertension (hazard ratio (HR) 3.1); nephrotic proteinuria (HR 1.9); interstitial fibrosis (HR 2.5); and sclerosed glomeruli (HR 1.8). The renal survival rates at 1, 5 and 10 years were 84, 55 and 33%, respectively, with a median renal survival of 61 months from the time of biopsy. CONCLUSION: The relatively rapid rate of progression of IgAN in India is suggestive towards a 'malignant' nature of the disease in this country.

Prediction of mortality in acute renal failure in the tropics.

Despite significant improvements in medical care, acute renal failure (ARF) remains a high risk for mortality. It is important to be able to predict the outcome in these patients in view of the emotional and ethical needs of the patients and to address questions of efficiency and quality of care. We analyzed the risk factors predicting mortality prospectively in a group of 265 patients using univariate and multiple logistic regression analysis. A prognostic model was evolved that included 10 variables. The model showed good discrimination [(receiver operating characteristic (ROC) area=0.91) and correctly classified 88.30% of patients. The variables significantly associated with mortality were coma odds ratio (OR)=9.8], oliguria (OR=4.9), jaundice (OR=3.7), hypotension (OR=3.1), assisted ventilation (OR=2.3), hospital acquired ARF (OR=2.3), sepsis (OR=2.2), and hypoalbuminemia (OR=1.7). Age and male gender were included in the model as they are clinically important. The score was validated in the same sample by boot strapping. It was also validated in a prospective sample of 194 patients. The model was calibrated by the Hosmer-Lemeshow goodness-of-fit test. It was compared with two generic illness scores and one specific ARF score and was found to be superior to them. The model was verified in different subgroups of ARF like hospital acquired, community acquired, intensive care settings, nonintensive care settings, due to sepsis, due to nonsepsis etiologies, and showed good predictability and discrimination.