Impact of focal segmental glomerulosclerosis over the past decade.

OBJECTIVE: This is a study on the demographics and clinical outcomes including the response to therapy of patients with focal segmental glomerulosclerosis (FSGS) over the past decade. MATERIALS AND METHODS: All histologically proven FSGS cases diagnosed between 2008 and 2018 were analyzed for their clinical, laboratory, and histological characteristics including treatment that could influence the disease progression and renal outcome of these patients. We used the Columbia Classification for FSGS for the renal biopsy. RESULTS: There were two subgroups of FSGS patients; those with nephrotic syndrome and those without nephrotic syndrome. Patients with FSGS with non-nephrotic syndrome had poorer survival rates compared to the nephrotic group. For those without nephrotic syndrome, the indices responsible for progression involved more tubular and blood vessel lesions in addition to glomerular pathology compared to those with nephrotic syndrome. Patients with FSGS with nephrotic syndrome responded to immunosuppressants more favorably compared to the non-nephrotic group, though both groups responded with decreasing proteinuria. The nephrotic group had a better 10-year long-term survival rate of 92 vs. 72% for the non-nephrotic group (log-rank 0.002). The 10-year survival for the whole group of FSGS patients was 64%. CONCLUSION: Our data suggest that in FSGS, one of the significant components of the disease is the vascular and tubular damage, apart from the underlying glomerular pathology, resulting in varying responses to therapy, and the difference is reflected in inherently poorer response to immunosuppressant therapy in those without nephrotic syndrome as opposed to those with nephrotic syndrome, who responded to immunosuppressant therapy (IST) with stabilization of renal function and had less blood vessel and tubular lesions.

Development and validation of a novel nomogram to predict diabetic kidney disease in patients with type 2 diabetic mellitus and proteinuric kidney disease.

PURPOSE: Differentiating between diabetic kidney disease (DKD) and non-diabetic kidney disease (NDKD) in patients with Type 2 diabetes mellitus (T2DM) is important due to implications on treatment and prognosis. Clinical methods to accurately distinguish DKD from NDKD are lacking. We aimed to develop and validate a novel nomogram to predict DKD in patients with T2DM and proteinuric kidney disease to guide decision for kidney biopsy. METHODS: A hundred and two patients with Type 2 Diabetes Mellitus (T2DM) who underwent kidney biopsy from 1st January 2007 to 31st December 2016 were analysed. Univariate and multivariate analyses were performed to identify predictive variables and construct a nomogram. The discriminative ability of the nomogram was assessed by calculating the area under the receiver operating characteristic curve (AUROC), while calibration was assessed using the Hosmer-Lemeshow goodness-of-fit test and calibration plot. Internal validation of the nomogram was assessed using bootstrap resampling. RESULTS: Duration of T2DM, HbA1c, absence of hematuria, presence of diabetic retinopathy and absence of positive systemic biomarkers were found to be independent predictors of DKD in multivariate analysis and were represented as a nomogram. The nomogram showed excellent discrimination, with a bootstrap-corrected C statistic of 0.886 (95% CI 0.815-0.956). Both the calibration curve and the Hosmer-Lemeshow goodness-of-fit test (p = 0.242) showed high degree of agreement between the prediction and actual outcome, with the bootstrap bias-corrected curve similarly indicating excellent calibration. CONCLUSIONS: A novel nomogram incorporating 5 clinical parameters is useful in predicting DKD in type 2 diabetes mellitus patients with proteinuric kidney disease.

Native kidney biopsies in older adults: disease spectrum, long-term kidney and patient survival and safety.

PURPOSE: Patients undergoing kidney biopsy are increasingly older. We aimed to evaluate the clinical utility of kidney biopsy, long-term clinical outcomes, and safety of high-risk biopsies in older adults undergoing kidney biopsy in a multi-ethnic Southeast Asian cohort. METHODS: We performed a single-center retrospective study of older patients (age ≥ 60 years) who underwent native kidney biopsies between June 2011 and March 2015. The primary long-term outcome of interest was a composite of ESKD or death. The safety outcome of interest was post-biopsy bleeding in the high-risk subgroup, defined by serum creatinine > 150 µmol/l. RESULTS: Older adults accounted for 153 of 545 (28.1%) native renal biopsies performed. The median age of these older adults was 66.6 (IQR 63.0, 70.6) years. Kidney dysfunction was frequent and severe in this cohort, with 41.2% having eGFR < 30 ml/min/m2 and 71.2% having nephrotic-range proteinuria at presentation. A significant proportion (124 patients; 81.0%) had treatable diagnoses. Of these, 90 (72.6%) received immunosuppressive therapy. On Kaplan-Meier analysis, patients with pauci-immune glomerulonephritis (p = 0.004) and diabetic nephropathy (p = 0.005) were at a significantly increased risk of the composite outcome of ESKD or death. On multivariate analysis, older age and lower eGFR were independently associated with ESKD or death and ESKD alone. Lupus nephritis and diabetic nephropathy were independently associated with ESKD or death, while immunosuppressant therapy was associated with reduced ESKD alone. In the high-risk subgroup, post-biopsy bleeding occurred in 19 (22.8%) patients. Desmopressin use was not associated with reduced bleeding complications. CONCLUSION: Our study confirmed the utility of kidney biopsy in older adult patients for diagnosis and management, although risk counselling and close monitoring for bleeding complications is necessary.

Changes in metabolic parameters and adverse kidney and cardiovascular events during glomerulonephritis and renal vasculitis treatment in patients with and without diabetes mellitus.

BACKGROUND: Cardiovascular disease causes significant morbidity and mortality in patients with glomerulonephritis, which is increasingly diagnosed in older individuals who may have diabetes mellitus (DM). We evaluated the impact of DM on metabolic profile, renal and cardiovascular outcomes during treatment and follow-up of individuals with glomerulonephritis. METHODS: We performed a retrospective cohort study of 601 consecutive adults with biopsy-proven glomerulonephritis for factors associated with kidney failure, hospitalization for cardiovascular events, and death. Biopsies with isolated diabetic nephropathy were excluded. RESULTS: The median patient age was 49.8 years (36.7-60.9 years) with estimated glomerular filtration rate of 56.7 mL/min/1.73 m2 (27.7-93.2 mL/min/1.73 m2). DM was present in 25.4%. The most frequent diagnoses were minimal change disease (MCD) or focal segmental glomerulosclerosis (FSGS) (29.5%), lupus nephritis (21.3%), immunoglobulin A (IgA) nephropathy (19.1%), and membranous nephropathy (12.1%). The median follow-up was 38.8 months (interquartile range [IQR], 26.8-55.8 months). Among 511 individuals with lupus nephritis, anti-neutrophil cytoplasmic antibody-associated vasculitis, MCD/FSGS, membranous nephropathy, and IgA nephropathy, 52 (10.2%) developed kidney failure at a median 16.4 months (IQR, 2.3-32.2 months), while 29 (5.7%) had cardiovascular-related hospitalizations at 12.9 months (IQR, 4.8-31.8 months) and 31 (6.1%) died at 13.5 months (IQR, 2.5-42.9 months) after diagnosis. Cox regression analysis found that baseline DM was independently associated with kidney failure (adjusted hazard ratio [HR], 2.07; 95% confidence interval [CI], 1.06-4.05, p = 0.03) and cardiovascular-related hospitalization (adjusted HR, 2.69; 95% CI, 1.21-5.98, p = 0.02) but not with mortality. CONCLUSION: DM was strongly associated with kidney failure and hospitalization for cardiovascular events in patients with biopsy-proven glomerulonephritis.

Evolution of IgA nephropathy in Singapore over four decades and a comparison of two cohorts from the first and fourth decade.

OBJECTIVE: In this study, we trace the changes in the clinical and histological pattern of IgA nephritis (IgAN) in Singapore as it has evolved over 4 decades and compare the clinical, demographic, histological, and renal outcome of patients with IgAN from the 1st decade and the 4th decade. MATERIALS AND METHODS: This is a retrospective study of all histologically proven IgAN diagnosed between 1976 and 2018. Clinical, laboratory, and histological characteristics between the 1st and the 4th decade, including treatment which could influence the disease progression and renal outcome of these two groups, were compared. We used the Oxford classification to compare the renal biopsy changes for these 2 decades as we were able to retrieve 125 renal biopsy tissues for the 1st cohort of IgAN studied in the 1970s for the comparative study. RESULTS: The commonest clinical presentation throughout the first 3 decades was asymptomatic hematuria and proteinuria (63, 52, and 49%, respectively). In the 4th decade, nephrotic syndrome (31%) was the commonest followed by asymptomatic hematuria and proteinuria (30%), hypertension (21%), and chronic renal failure (11%). The data showed that treatment can modify the Oxford MEST - Crescent scores. Renin-angiotensin system (RAS) blockers modified the S scores, immunosuppressants modified the T and C scores, and combination therapy with RAS blockers and immunosuppressants modified the E, S, and T scores. CONCLUSION: The Oxford MEST classification offers a robust and expressive classification for early and late disease progression with respect to the development of end-stage renal disease (ESRD). E and S seem to be indices of continuing disease activity with progressive glomerulosclerosis, probably still amenable to therapy, but T was a predictive indicator for those destined for ESRD and no longer amenable to therapy.

The Value of Renal Biopsy in Non-Insulin-Dependent Diabetes Mellitus in Singapore over the Past Two Decades.

OBJECTIVE: This study on the prevalence of diabetic nephropathy (DN) and coexistence of non-diabetic renal disease (NDRD) in a cohort of 255 non-insulin-dependent diabetes mellitus (NIDDM) patients aims to determine the value of performing renal biopsies in these patients and elucidate the factors which could affect their progression to end-stage renal disease (ESRD). METHODS: Among 255 NIDDM patients, 93 had DN alone, 69 had NDRD alone, and the remaining 93 had DN plus NDRD (mixed group). The indications for renal biopsy were based on clinical suspicion of superimposed NDRD, including heavy or rapidly increasing proteinuria, renal impairment even though diabetes is of relatively short duration, rapidly declining renal function, and presence of hematuria with dysmorphic red blood cells suggesting presence of glomerulonephritis. RESULTS: The following were predictors of ESRD: high systolic BP at biopsy, longer duration of diabetes, heavy proteinuria, and presence of diabetic retinopathy. Comparing patients in the NDRD group with the DN group and the mixed group, the NDRD group had lower serum creatinine and higher eGFR with lower urinary proteinuria and higher serum albumin at presentation and on follow-up. Kimmelstiel-Wilson nodules were associated with a poorer prognosis leading to a higher occurrence of ESRD among patients with DN. CONCLUSION: Renal biopsy is of value in indicating the prognosis of NIDDM patients with DN based on the diabetic lesions. For NIDDM patients with atypical course and suspicion of associated NDRD, a renal biopsy would enable us to diagnose the underlying NDRD and offer appropriate therapy. Most nephrologists would consider renal biopsy for an NIDDM patient based on clinical indications like atypical clinical course and suspicion of an associated NDRD, but they would not perform a routine renal biopsy like for a CKD patient, unless it is for a research indication.

A Global Evolutionary Trend of the Frequency of Primary Glomerulonephritis over the Past Four Decades.

OBJECTIVE: The pattern of glomerulonephritis (GN) in Singapore is compared with that of 19 other countries to review changing trends in the evolution of GN in Asian, Eastern, and Western countries. METHOD: Three thousand two hundred and eighty-nine renal biopsies in Singapore were reviewed and compared with that of 19 other countries. RESULTS: IgA nephritis is on the decline in many countries, including Singapore, though it still remains the commonest GN in Singapore. Membranous GN that if used to be more frequently present in Western countries has also declined though it continues a rising trend in countries such as Singapore and China. Worldwide, the frequency of focal sclerosing glomerulosclerosis (FSGS) continues to increase in many countries, but in some countries, the frequency is still low with mesangiocapillary GN remaining indigenous. CONCLUSION: Urbanization and socioeconomic changes and less exposure to parasitic and other infestations have transformed Singapore's pattern, which is tending toward that of more developed countries. Antigenic exposure due to lifestyle changes, environmental, and industrial pollution are significant contributory factors that affect the evolutionary trend of GN in many countries. The rising trend in the frequency of FSGS may reflect aging and obesity.

Changes in primary glomerulonephritis in Singapore over four decades
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This review of 3,289 native kidney biopsies over the past four decades in Singapore documents the changing pattern of biopsy-proven glomerulonephritis (GN)from that of a third world country to that of a developed nation. In the 1st decade, mesangial proliferative GN was the most common form of primary GN, similar to the Asian region. In the 2nd decade, the percentage of mesangial proliferative GN decreased, but membranous GN became more common, as was seen in China and Thailand. In the 3rd decade, focal segmental glomerulosclerosis (FSGS) and membranous nephropathy continued to rise, but it was only recently, in the 4th decade, that FSGS prevalence increased dramatically, although membranous nephropathy continues to increase in some Asian countries. In the last decade in Singapore, Malaysia, and Japan, prevalence of IgA nephritis has decreased but remains the most common GN. The percentage of FSGS continues to increase in many countries like in Italy, United States of America, United Kingdom, China, and Malaysia. We surmise that socioeconomic factors play significant roles in the evolution of the renal biopsy pattern.
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30-year follow-up study of IgA nephritis in a Southeast Asian population: an evaluation of the Oxford histological classification
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BACKGROUND: In 1985 we reported that 11% of a cohort of 151 patients with IgA nephritis (IgAN) had developed end-stage renal disease (ESRD) after a follow-up period of 5 years. 15 years later, 35% had developed ESRD. METHODS: We retrieved 125 stored renal biopsy paraffin blocks of the original cohort. From these, 102 patients were included in the present study and scored according to the Oxford classification as 21 specimens with less than 8 glomeruli were excluded and in 2 others, tissue samples were too tiny for a re-block. ESRD was ascertained by linking the study cohort to the Singapore Renal Registry at the National Registry of Diseases Office. RESULTS: Renal survival curves for each of the Oxford MEST lesions: endocapillary proliferation (E) (p < 0.04), segmental glomerulosclerosis (S) (p < 0.05), tubular atrophy/interstitial fibrosis (p < 0.0001) were significantly associated with ESRD. Mesangial hypercellularity, less commonly associated with progressive chronic kidney disease (CKD) in the study, was independently associated with ESRD at 30 years (p < 0.03). In this cohort, E and S were associated with lower eGFR at presentation and doubling of serum creatinine in the first 5 years. This study's initial 5 years was representative of the "natural history" of IgAN since no renin-angiotensin system (RAS) blockers or immunosuppression were administered. This represents the early phase of disease progression. E and S may be considered "early disease activity predictors". CONCLUSION: Mesangial hypercellularity and tubular atrophy/interstitial fibrosis (M1 and T1/T2 lesion) of the Oxford classification independently predicted long term ESRD.
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Warfarin related nephropathy: a case report and review of the literature.

BACKGROUND: Warfarin related nephropathy is one of the potential complications of warfarin therapy. Despite the well described histological entity, the clinical course and approach to warfarin related nephropathy in patients requiring life-long anticoagulation is however not well described in the literature. CASE PRESENTATION: We report the clinical course of a 56 years old Chinese lady who presented with over anti-coagulation and acute kidney injury while on warfarin therapy for permanent atrial fibrillation and mechanical valve replacement. Renal biopsy was performed as the acute kidney injury was persistent despite normalization of the International Normalized Ratio and the diagnosis of warfarin related nephropathy was made. Temporary interruption of anti-coagulation, in combination with oral N-acetylcysteine resulted in subsequent stabilization of renal function. CONCLUSION: The diagnosis of warfarin induced nephropathy should be considered in patients presenting with unexplained acute kidney injury and over anti-coagulation. Awareness of this clinical entity is important for clinician managing anti-coagulation therapy and renal function should be monitored regularly in patients who are on warfarin therapy.

Aliskiren and losartan trial in non-diabetic chronic kidney disease.

INTRODUCTION: This is a report of a clinical trial on the therapeutic efficacy and safety of combined aliskiren and losartan (an angiotensin II receptor blocker (ARB)) versus aliskiren alone and ARB alone in non-diabetic chronic kidney disease (CKD) over a 3-year period. MATERIALS AND METHODS: This was a randomised trial in 155 patients with non-diabetic CKD comparing aliskiren (150 mg/day) (n=52) versus losartan (100 mg/day) (n=52) and the third group aliskiren (150 mg/day) combined with losartan (100 mg/day) (n=51). The trial utilised primary renal end points of eGFR <15 ml/min or end-stage renal failure. RESULTS: All three groups had significant reduction of proteinuria (p<0.001 for all). The changes in eGFR, total urinary protein from baseline to each year were not significantly different between the three therapeutic groups. CONCLUSION: This study in non-diabetic CKD patients showed that combination therapy with aliskiren and ARB was as efficacious as aliskiren alone and ARB alone. There was one patient who developed a non-fatal stroke in the combined aliskiren and ARB group while the other two groups had none.