Estimation of risk for major bleeding in native kidney biopsies in patients with multiple risk factors.

BACKGROUND AND AIMS: Individuals undergoing kidney biopsy are increasingly older and may have concurrent illnesses that cause deranged hematological and renal parameters that are associated with post-biopsy bleeding. We aimed to develop a clinical risk model to quantify bleeding risks in high-risk individuals with multiple risk factors. METHODS: Single-center retrospective cohort study of consecutive adults with serum creatinine ≥ 2 mg/dL (176 µmol/L) and had ultrasound-guided percutaneous native kidney biopsies between June 2011 and July 2015 in our tertiary referral center. The primary outcome was major bleeding, defined as need for red cell transfusion, radiological or surgical intervention, or if bleeding led to death within 7 days after kidney biopsy. RESULTS: Among 184 native kidney biopsies with serum creatinine ≥ 2 mg/dL, median age was 54.1 years and eGFR was 18.8 ml/min/1.73 m2. Major bleeding occurred in 19 biopsies (10.3%). Multivariate analysis accounting for age, weight, hemoglobin, platelet, prothrombin time and urea found that higher hemoglobin (adjusted OR 0.51, 95% CI 0.33-0.79, p = 0.003) and platelet (adjusted OR 0.99, 95% CI 0.98-0.99, p = 0.01) were independently associated with reduced major bleeding. A risk model that included (1) age ≥ 62 years old, (2) hemoglobin < 10 g/dL and (3) platelets ≤ 216 × 109/L as categorical variables predicted major bleeding post-biopsy. CONCLUSION: We developed a risk model that included multiple risk factors to quantify bleeding risks in native kidney biopsies with renal impairment.

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.

Clinical course of Immunoglobulin A nephropathy with crescents in a multi-ethnic Southeast Asian cohort.

AIM: Clinical presentation and course of Immunoglobulin A nephropathy vary by ethnicity and geography and significance of extracapillary proliferation or crescents (IgAN-C) in Southeast Asia is not well described. We aimed to describe the clinical course of IgAN-C in Singapore. METHODS: Retrospective cohort study of adult biopsy-proven IgAN diagnosed between February 2011 and October 2016 in 2 hospital-based nephrology units. Outcome was chronic kidney disease (CKD) progression, defined as reduction in eGFR ≥50% or end stage renal failure (ESRF). RESULTS: One hundred and forty-five patients were studied. Among individuals with IgAN-C (n = 44, 30%), 38 patients had cellular or fibrocellular crescents in 1 to 25% of the glomeruli and 6 had crescents in >25%. Median eGFR was 54 (33, 83) mL/min/1.73 m2 . Compared to IgAN without crescents, IgAN-C had greater proteinuria (median 2.9 [1.4, 5.4] g/g vs 1.9 [1.1, 3.6] g/g, P = .03) and more had endocapillary hypercellularity (96% vs 39%, P < .001). IgAN-C were also more likely to receive immunosuppressants (66% vs 43%, P = .01) such as prednisolone (63% vs 38%, P = .006) and cyclophosphamide (12% vs 2%, P = .03). Median follow up was 27 (12, 46) months. IgAN-C were more likely to achieve proteinuria reduction ≥50% at 6 months (66% vs 44%, P = .03). CKD progression within 12 months was not different among those with and without crescents (13% vs 10% respectively, P = .73). However, immunosuppressant treatment of IgAN-C was associated with reduced ESRF (0 vs 20%, P = .03). CONCLUSION: Immunosuppressants may attenuate the risk of ESRF in IgAN-C.

Desmopressin for the prevention of bleeding in percutaneous kidney biopsy: efficacy and hyponatremia.

BACKGROUND: Desmopressin is used to reduce bleeding complications for kidney biopsies with azotemia but little is known about desmopressin-induced hyponatremia in these individuals. We aimed to evaluate the impact of desmopressin prophylaxis on severe hyponatremia and bleeding after kidney biopsies in individuals with renal impairment. METHOD: This is a single-center retrospective cohort study of consecutive adults with serum creatinine ≥ 150 µmol/L and had ultrasound-guided percutaneous native or transplant kidney biopsies between June 2011 and July 2015. Data were retrieved from electronic medical records. Primary outcomes were the use of desmopressin prophylaxis and severe hyponatremia (serum sodium ≤ 125 mmol/L) within 7 days post-biopsy. Secondary outcome was post-biopsy bleeding. RESULTS: 240 native kidney and 196 allograft biopsies were performed. Median age was 51 (IQR 42.3, 60) years and eGFR was 21.9 (12.9, 30.1) ml/min/1.73 m2. Although patients prescribed desmopressin prophylaxis (n = 226) had higher serum creatinine [279 (201, 392) vs. 187 (160, 241), p < 0.001], bleeding (15.0% vs. 13.3%, p = 0.60) was not significantly different with and without desmopressin. Severe hyponatremia occurred in 30 biopsies (6.9%) with nadir serum sodium level of 122 (119, 124) mmol/L at 3 (2, 5) days after biopsy, more frequently among those with desmopressin prophylaxis (10.7% vs. 3.0%, p = 0.002). Multi-variate analysis found that pre-biopsy serum sodium level [adjusted OR 0.80 (95% CI 0.72, 0.90), p < 0.001] and desmopressin prophylaxis [adjusted OR 4.02 (95% CI 1.58, 10.21), p = 0.003] were independently associated with severe hyponatremia after kidney biopsy. CONCLUSION: Pre-biopsy desmopressin was associated with severe hyponatremia in individuals with renal impairment; hence, susceptible patients given desmopressin should be closely monitored.

Long-term renal outcomes in multi-ethnic Southeast Asians with lupus nephritis: a retrospective cohort study.

BACKGROUND: Renal involvement is common among Asians with systemic lupus erythematosus and long-term renal outcomes have been described in homogeneous Caucasian and East Asian populations with lupus nephritis, but data are scarce for other ethnicities. AIM: To evaluate the incidence and risk factors for progressive chronic kidney disease (CKD) in multi-ethnic Southeast Asians with lupus nephritis. METHODS: This is a single-centre retrospective cohort study of adults with biopsy-proven lupus nephritis diagnosed between May 2001 and May 2009. Demographic and clinical data were retrieved from electronic medical records. Patients were excluded if baseline comorbid, renal function or pharmacotherapy data were incomplete or if they default follow-up within 3 months from time of diagnosis. Primary outcome was progressive CKD, defined by end-stage renal disease or persistent doubling of serum creatinine or reduction in eGFR ≥50% for ≥3 months from baseline. RESULTS: We studied 113 patients with newly diagnosed biopsy-proven lupus nephritis. Median age was 42 (interquartile range 29-52) years; the majority were Chinese (76%; Malay 13% and others 11%) and female (81%). Two-thirds had International Society of Nephrology and Renal Pathology Society Class III or IV nephritis; serum creatinine was 86 (67-125) µmol/L with heavy proteinuria (6.3 (2.5-12.2) g/g creatinine). Median follow-up was 110 (83-142) months. Remission (partial and complete) occurred in 96% at 3.1 (1.6-5.2) months after diagnosis. Among patients who achieved remission, 56% had disease relapse at 19.0 (6.0-40.2) months after remission. Patients with progressive CKD (n = 13, 11%) had lower baseline CKD Epidemiology Collaboration estimated glomerular filtration rate (37.3 (16.5-82.0) vs 79.4 (57.5-101.0) mL/min/1.73 m2 , P = 0.03) and higher chronicity index (5 (3-6) vs 3 (2-3), P = 0.04) than those who did not. Remission, early remission within 6 months, complete remission and non-relapse were less frequently associated with progressive CKD (P < 0.01). CONCLUSION: Multi-ethnic Southeast Asians with biopsy-proven lupus nephritis had high remission rates and low incidence of progressive CKD. Progressive CKD was associated with poorer baseline renal function, higher histological chronicity index, failure to achieve remission and occurrence of relapse.

30-year follow-up study of IgA nephritis in a Southeast Asian population: an evaluation of the Oxford histological classification
.

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.
.

Long-Term Risk of Progressive Chronic Kidney Disease in Patients with Severe Acute Kidney Injury Requiring Dialysis after Coronary Artery Bypass Surgery.

AIM: Few studies have evaluated patients after cardiac surgery for subsequent chronic kidney disease (CKD) which increases cardiovascular morbidity and mortality. This study aimed to ascertain the long-term renal outcome in adult patients with severe acute kidney injury (AKI) after coronary artery bypass graft (CABG) surgery. METHODS: This is a single-center retrospective cohort study of consecutive adult patients who received acute dialysis for AKI after CABG between February 8, 2009 and January 30, 2011. Data on pre- and intra-operative factors were retrieved from electronic medical records. The primary endpoint was CKD progression as defined by dialysis dependence or doubling of serum creatinine from the pre-operative level. Secondary endpoints included in-hospital mortality and renal function at 3 months and 1 year. RESULTS: Fifty-five patients required acute dialysis after CABG. The median age was 67 years (IQR: 61, 75), and 70.9% were male. Median pre-operative serum creatinine was 157 µmol/l (IQR: 122, 203). A total of 19 patients (34.5%) died. The median follow-up time for hospital survivors was 44.2 months (IQR: 25.0, 49.4) after surgery. Among the 36 survivors, 14 patients (38.9%) reached the primary endpoint. Patients with CKD progression had higher pre-operative serum creatinine [median 214 µmol/l (IQR: 159, 399) vs. 155 µmol/l (112, 187), p = 0.015] and lower eGFR [median 20.4 ml/min/1.73 m(2) (IQR: 11.9, 38.2) vs. 39.9 ml/min/1.73 m(2) (25.9, 55.5), p = 0.027] compared to those who did not have CKD progression. CONCLUSION: Patients with severe AKI after CABG are at high risk of long-term renal dysfunction and should be monitored regularly for deterioration.