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S M Korbet

Publications and source records attributed to S M Korbet.

At least 19 recordsLinked to original sources
PubMed2001

Significance of histologic patterns of glomerular injury upon long-term prognosis in severe lupus glomerulonephritis.

BACKGROUND: Patients with systemic lupus erythematosus have a spectrum of glomerular disease, but the different patterns of glomerular injury identified within the general category of "severe" lupus glomerulonephritis are responsible for much of the morbidity and mortality in this disease. The glomerular injury patterns seen with severe lupus glomerulonephritis have been separated into distinct histopathologic groups to determine whether they can predict long-term patient outcome. METHODS: We analyzed the clinical follow-up of 85 patients participating in a controlled prospective therapeutic trial for the treatment of severe lupus glomerulonephritis conducted from April 1981 to December 1988, with an average follow-up of 10 years. Patients were classified according to the 1982 World Health Organization classification for lupus glomerulonephritis. RESULTS: During the course of follow-up [120 +/- 65 (SD) months], 60% of patients with category IV (diffuse proliferative glomerulonephritis) lesions entered a remission compared with only 38% of patients with category III (> or =50%, focal and segmental glomerulonephritis) lesions and 27% of patients with category Vc (> or =50%) and Vd (P < 0.05). Renal survival at 10 years was 75% for those with category IV lesions, 47% for patients with category Vc (> or =50%) and Vd, and 52% for patients with category III (> or =50%) lesions (P < 0.05). Based on multivariate analysis, patients with category III (> or =50%) or Vc (> or =50%) and Vd lesions had a relative risk of progression to end-stage renal disease 2.9 times that of category IV patients (P < 0.01), while the likelihood of entering a remission was 8.2 times greater for category IV patients (P = 0.0001). CONCLUSION: The histopathologic categorization among patients with severe lupus glomerulonephritis provides information relevant to their long-term outcome.

Adult↗
PubMed2000

A multicenter study of noncompliance with continuous ambulatory peritoneal dialysis exchanges in US and Canadian patients.

Recent evidence suggested that noncompliance (NC) with continuous ambulatory peritoneal dialysis (CAPD) exchanges may be more common in US than in Canadian dialysis centers. This issue was investigated using a questionnaire-based method in 656 CAPD patients at 14 centers in the United States and Canada. NC was defined as missing more than one exchange per week or more than two exchanges per month. Patients were ensured of the confidentiality of their individual results. Mean patient age was 56 +/- 16 years, 52% were women, and 39% had diabetes. The overall admitted rate of NC was 13%, with a rate of 18% in the United States and 7% in Canada (P < 0.001). NC was more common in younger patients (P < 0.0001), those without diabetes (P < 0.001), and employed patients (P < 0.05). It was also more common in black and Hispanic than in Asian and white patients (P < 0.001). NC was more common in patients prescribed more than four exchanges daily (P < 0.0001) but was not affected by dwell volume. On multiple regression analysis, the independent predictors of NC, in order of importance, were being prescribed more than four exchanges per day, black race, being employed, younger age, and not having diabetes. Being treated in a US unit did not quite achieve significance as a multivariate independent predictor. These findings suggest that NC is not uncommon in CAPD patients and is more frequent in US than in Canadian patients. However, country of residence is less powerful as a predictor of NC than a variety of other demographic and prescription factors.

Adult↗
PubMed2000

Factors predictive of outcome in severe lupus nephritis. Lupus Nephritis Collaborative Study Group.

In 1992, we published the results of a prospective, controlled trial of aggressive therapy (high-dose prednisone plus oral cyclophosphamide alone or with plasmapheresis) in 86 patients with severe lupus nephritis. During this study, remission (serum creatinine < or =1.4 mg/dL [< or =123 micromol/L] and proteinuria < or =330 mg/d of protein) in renal disease occurred in 37 patients (43%). To assess the long-term effect of remission on patient and renal survival, we now report the results of our extended follow-up of these patients. After an average of 10 years of follow-up in the 86 patients, patient survival rates at both 5 and 10 years were 95% in the group that had a remission and 69% at 5 years and 60% at 10 years in the no-remission group (P < 0.001). Renal survival rates were 94% at both 5 and 10 years in the remission group compared with 46% at 5 years and 31% at 10 years in the no-remission group (P < 0. 0001). Features predictive of remission included stable renal function after 4 weeks on therapy, category IV lesion, lower chronicity index, white race, lower urine protein excretion level at baseline, and lower baseline serum creatinine level. The features predictive of end-stage renal disease were higher baseline serum creatinine level, presence of anti-Ro antibodies, and failure to attain a remission. Thus, in patients with the most severe forms of lupus nephritis, a remission of clinical renal abnormalities is associated with dramatic improvement in long-term patient and renal survival.

Adult↗
PubMed2000

Polymicrobial peritonitis in continuous ambulatory peritoneal dialysis patients.

We retrospectively evaluated 232 continuous ambulatory peritoneal dialysis (CAPD) patients entering our program from January 1, 1987, to December 31, 1997, for polymicrobial peritonitis. Polymicrobial peritonitis occurred in 16% of the patients (polymicrobial-peritonitis group), whereas 52% of the patients had peritonitis episodes with only a single organism (single-organism group), and 32% of the patients had no episode of peritonitis. Polymicrobial peritonitis accounted for 8% of the 554 peritonitis episodes, occurred after 23 +/- 20 months on peritoneal dialysis (PD), and was preceded by greater than three episodes of peritonitis in 73% of the patients. Peritonitis rates were greater in the polymicrobial-peritonitis group compared with patients in the single-organism group (1.8 versus 1.2 episodes/patient-year; P: < 0.001). The majority of polymicrobial infections involved gram-negative and/or fungal pathogens, but in 21% of the episodes, only gram-positive organisms were identified. An intra-abdominal process was identified in only 7% of the patients. Catheter loss overall was greatest in the polymicrobial-peritonitis group (65% versus single-organism group, 30% versus patients without peritonitis, 5%; P < 0.001), but only 33% of the polymicrobial infections resulted in catheter loss. At last follow-up, 70% of the patients in the polymicrobial-peritonitis group had permanently transferred to hemodialysis compared with 25% from the single-organism group and 15% from the no-peritonitis group (P < 0.001). In conclusion, polymicrobial peritonitis is an infrequent but serious complication of CAPD that occurs late in the course of PD and is often preceded by recurrent episodes of peritonitis. Polymicrobial peritonitis is rarely the result of a catastrophic intra-abdominal process, and although the majority of patients can be successfully treated without catheter removal, the long-term prognosis is poor, with a high rate of transfer to hemodialysis.

Adult↗
PubMed2000

Patient survival among incident peritoneal dialysis and hemodialysis patients in an urban setting.

We retrospectively evaluated 432 patients (336 black; 78%; and 96 white; 22%) incident to our peritoneal dialysis (PD; 195 patients; 45%) and hemodialysis (HD; 237 patients; 55%) programs from January 1987 to December 1997 who survived their first 90 days of dialysis therapy. Black patients comprised 70% of the PD and 84% of the HD patients (P: < 0.01). PD patients were more often men and younger than HD patients and less often had diabetes (40% versus 56% of HD patients; P: < 0.01) and cardiac disease (44% versus 58% of HD patients; P: < 0.01) than HD patients. Adjusting for baseline clinical and comorbid features, patient survival was determined by Cox regression analysis. Survival was better on PD therapy overall (relative risk [RR] for PD versus HD, 0.80; 1-, 2-, and 5-year survival rates, 90%, 77%, and 43% on PD versus 88%, 72%, and 35% on HD, respectively; P: = 0.21) and among black patients (RR for PD versus HD, 0.69; 1-, 2-, and 5-year survival rates, 92%, 80%, and 52% on PD versus 88%, 74%, and 40% on HD, respectively; P: = 0.09), but these were not statistically significant. The RR for PD versus HD was 1.08 for white patients (1-, 2-, and 5-year survival rates, 82%, 61%, and 23% for PD versus 82%, 62%, and 24% for HD; P: = 0.79). Significant predictors of mortality were race (RR for whites versus blacks, 1.51), age (RR, 1.03), cardiac disease (RR, 1.57), baseline albumin level (RR, 0.60), baseline serum creatinine level (RR, 0.91), baseline blood urea nitrogen level (RR, 1.01), and baseline weight (RR, 0.98). In conclusion, patient survival on dialysis therapy is significantly better for black patients and for patients entering dialysis with signs of adequate nutrition (increased weight and creatinine and albumin levels) and without evidence of cardiac disease. In an urban dialysis program, we find that adjusted patient survival on PD equals or is better than that on HD therapy, particularly among black patients, making PD a viable alternative to HD in our patient population.

Humans↗
PubMed2000

The treatment of primary focal segmental glomerulosclerosis.

Nephrotic patients with primary focal segmental glomerulosclerosis (FSGS) have a poor prognosis with 50% progressing to end stage renal disease (ESRD) over 3 to 8 years. The achievement of a remission in proteinuria has been associated with a significantly improved renal survival as compared to those patients not attaining a remission. Unfortunately, spontaneous remissions are rare in FSGS, and the response to therapy has historically been poor. Recent experience with more aggressive immunosuppressive therapy has lead to an increase in the remission rate for FSGS patients and given rise to optimism in the treatment of this glomerulopathy.

Anti-Inflammatory Agents↗
PubMed2000

Von Hippel-Lindau disease with multiple malignant renal tumors: the importance of genetic testing.

We present an adult man who, while being evaluated for gross hematuria, was found to have polycystic kidneys and multiple bilateral renal cell carcinomas. Further evaluation and the presence of a significant family history of cancer suggested the diagnosis of von Hippel-Lindau disease. Through the aid of genetic testing, this unusual diagnosis was confirmed and led to the identification of other family members with the von Hippel-Lindau gene. Patients with von Hippel-Lindau disease have an increased incidence of malignant carcinomas and the syndrome can mimic the presentation of other cystic diseases of the kidney. Early diagnosis and genetic screening of family members is essential to improve the prognosis and survival of those affected.

Adult↗
PubMed1999

Racial differences in survival in an urban peritoneal dialysis program.

We retrospectively evaluated 233 incident patients (61% black, 27% white, and 12% Hispanic/Asian) to our peritoneal dialysis (PD) program from January 1987 to September 1997 to identify any possible racial differences in patient survival. Information collected included clinical features, comorbid conditions, nutritional status, and dialysis dose at initiation of dialysis. The average age was 52 +/- 16 (SD) years, and 49% were men. Diabetes mellitus was present in 41% of patients. Overall follow-up was 31 +/- 24 (median 26) months during which time 21% of patients underwent transplant, 29% of patients transferred to hemodialysis (HD), and 42% of patients died. The Cox proportional hazards analysis, based on intent-to-treat, identified age (RR: 1.03), race (RR: 2.35, white versus black), cardiac disease (RR: 1.97), and serum albumin (RR: 0. 44) to independently predict mortality. Further analysis was performed based on diabetic status, and the analysis identified age (RR: 1.06), race (RR: 2.45, white versus black), and peripheral vascular disease (RR: 2.88) as predictors of mortality in diabetic patients. In nondiabetic patients, age (RR: 1.03), race (RR: 2.24, white versus black), cardiac disease (RR: 2.48), cerebrovascular disease (RR: 3.17), and serum albumin (RR: 0.39) were significant predictors of mortality. The significance of race persisted even after adjusting patients transferring to hemodialysis. The adjusted patient survival at 1, 2, and 5 years was 94%, 87% and 53% for black patients, and 86%, 72%, and 23% for white patients. The adjusted patient survival in diabetics at 1, 2, and 5 years was 92%, 79%, and 37% for black patients, and 82%, 56%, and 9% for white patients. The adjusted patient survival in nondiabetics at 1, 2, and 5 years was 94%, 91%, and 63% for black patients, and 88%, 82%, and 35% for white patients. In conclusion, long-term patient survival is better for black patients than white patients in our peritoneal dialysis program. Peritoneal dialysis should be considered a viable dialytic option for black patients entering an end-stage renal disease program.

Adult↗
PubMed1999

Clinical picture and outcome of primary focal segmental glomerulosclerosis.

Patients with primary focal segmental glomerulosclerosis (FSGS) present with proteinuria (often the nephrotic syndrome), microscopic haematuria, hypertension and renal insufficiency. Overall, this glomerular lesion is seen in approximately 20% of nephrotic adults and children, but is observed much more commonly in the black than the white population (prevalence as high as 80%). Characteristically, nephrotic patients, particularly those with massive proteinuria, have a significantly poorer prognosis than non-nephrotic patients, with 50% progressing to end-stage renal disease (ESRD) over 3-8 years as compared with a 10-year survival of >80%, respectively. In addition, the recurrence rate of this lesion is high in transplanted patients with primary FSGS. When clinical and histological features at presentation have been evaluated by multivariate analysis, the significant positive predictors of progression to ESRD have consistently been the serum creatinine (>1.3 mg/dl), amount of proteinuria and the presence of interstitial fibrosis (> or =20%). The only factor found to be a significant negative predictor of progression to ESRD has been the achievement of a remission in proteinuria. Unfortunately, spontaneous remissions are rare in FSGS, occurring in < or =6% of patients. The factor identified as most associated with achieving a remission in nephrotic patients with primary FSGS has been treatment.

Adult↗
PubMed1999

Focal segmental glomerulosclerosis: prognostic implications of the cellular lesion.

The cellular lesion (CELL), seen in some patients with primary focal segmental glomerulosclerosis (FSGS), comprises proliferation, hypertrophy, and pathologic changes in the cells overlying the glomerular scar. The prognosis of the cellular lesion was retrospectively studied in 100 patients with FSGS (43 had FSGS-CELL and 57 had FSGS without the cellular lesion (classic segmental scar [CS]). Patients with the FSGS-CELL lesion were more often black and severely proteinuric and developed more end-stage renal disease (ESRD). Nephrotic patients with FSGS-CELL (n = 39) were more proteinuric at presentation than patients with FSGS-CS (n = 36). ESRD developed more frequently in patients with the FSGS-CELL (17 of 39, 44% versus 5 of 36, 14%, P = 0.005), and patients with extensive FSGS-CELL (> or = 20% glomeruli) were mainly black (94%), severely nephrotic (67%, >10 g/d), and had a poor response to treatment (23% remission). In nephrotic patients, initial serum creatinine, interstitial expansion > or = 20%, and CELL independently predicted ESRD. However, the rates of remission in treated nephrotic patients with FSGS-CELL and FSGS-CS were the same (9 of 17, 53% versus 17 of 39, 52%), and patients in both groups who achieved a remission had a 5-yr survival of 100%. Steroid treatment was the only variable that predicted remission. Patients with the FSGS-CELL have an increased prevalence of ESRD, but the improved prognosis associated with remission is so significant that a therapeutic trial is warranted in all nephrotic FSGS patients, regardless of the presence of the cellular lesion.

Adult↗
PubMed1998

Evaluation of ultrafiltration failure.

The evaluation of ultrafiltration failure is embarked upon when a patient has persistent problems with symptoms and signs of fluid overload. Fluid overload is a common problem in peritoneal dialysis (PD) patients and the risk of its occurrence increases with time on dialysis. Although often attributed to changes in peritoneal membrane function (membrane failure), there are a number of potential, and frequently more common factors that can contribute to the failure of adequate fluid removal in patients on PD. Many of the causes of ultrafiltration failure may be apparent after an initial informal evaluation. However, if after this the etiology remains unexplained, a systematic approach to the differential diagnosis of this problem can be utilized with the use of the peritoneal equilibration test. Once a diagnosis is confirmed, a logical therapeutic plan can be formulated.

Biological Transport↗
PubMed1996

The racial prevalence of glomerular lesions in nephrotic adults.

We retrospectively evaluated the prevalence of primary glomerular lesions in adults who had a renal biopsy for nephrotic proteinuria. From July 1975 to May 1994, 340 patients undergoing renal biopsies evaluated at Rush-Presbyterian-St Lukes Medical Center had the primary glomerular lesions of minimal-change disease, focal segmental glomerular sclerosis (FSGS), membranous glomerulonephritis (MGN), membranoproliferative glomerulonephropathy, immunoglobulin A nephropathy, and immunotactoid glomerulopathy. The patients had a mean age of 43 +/- 17 years, 57% were male, and 50% were white, 36% were black, 7% were of other race, and 7% were of unknown race. The distribution of lesions for black patients was minimal-change disease 14%, FSGS 57%, MGN 24%, membranoproliferative glomerulonephritis 2%, immunoglobulin A 2%, and immunotactoid glomerulopathy 1%; for white patients, the distribution of lesions was minimal-change disease 20%, FSGS 23%, MGN 36%, membranoproliferative glomerulonephropathy 6%, immunoglobulin A 8%, and immunotactoid glomerulopathy 6%. The prevalence of FSGS was significantly greater (P < 0.0001) and that for MGN, immunoglobulin A, and immunotactoid glomerulopathy was significantly less (P < 0.05) for black patients compared with white patients. In a logistic regression analysis, race remained the only significant predictor of FSGS (P = 0.0001), with black patients four times as likely to have FSGS as white patients. The distribution of lesions among white patients was similar based on gender, age, and biopsy period. For black patients the distribution was also similar based on gender and age, but over 20 years the incidence of FSGS increased from 39% (1975 to 1984) to 64% (1985 to 1994) (P < 0.01). Thus, significant racial differences in the distribution of primary glomerular lesions exists. This has important prognostic and therapeutic implications for nephrotic adults.

Adolescent↗
PubMed1996

Timing of complications in percutaneous renal biopsy: what is the optimal period of observation?

Percutaneous renal biopsies of native kidneys were performed in 394 adult patients (aged > or = 15 years) at Rush-Presbyterian-St Lukes Medical Center between February 1983 and April 1995. All biopsies were performed with the use of real-time ultrasound; the last 169 were done with the use of an automated biopsy needle. All patients had a normal bleeding time and were observed for 23 to 24 hours postbiopsy. A biopsy-related complication occurred in 52 patients (13%). Minor complications, defined as gross hematuria, or perinephric hematoma that resolved without the need for transfusion or intervention, occurred in 26 patients (6.6%). Major complications, defined as those requiring a transfusion, invasive procedure, or resulting in septicemia, also occurred in 26 patients (6.6%). Patients with complications did not differ from those without complications at the time of biopsy with respect to age, blood pressure, serum creatinine, or bleeding time, but did have a lower prebiopsy hemoglobin level (11 +/- 2 g/dL v 12 +/- 2 g/dL; P < 0.05). No significant difference in age, blood pressure, serum creatinine, or hemoglobin level at the time of biopsy was observed in patients with major complications compared with those with minor complications. The time interval between the procedure and the identification of a complication was available for 44 patients (85%): 24 (92%) had a major complication and 20 (77%) had a minor complication. The complication was apparent within 24 hours in all but one patient (98%). Overall the complication was identified in only 52% of patients at < or = 4 hours, 77% at < or = 8 hours, and 95% at < or = 12 hours. Major complications were identified in 46% of patients at < or = 4 hours, 79% at < or = 8 hours, and 100% at < or = 12 hours. In patients with major complications the postbiopsy hemoglobin decreased by 3.2 +/- 1.8 g/d; this was significantly greater (P < 0.0001) than the decrease seen in patients with minor complications (1.2 +/- 1.0 g/dL) or in patients with no complications (0.9 +/- 0.8 g/dL). When considering a percutaneous renal biopsy as an outpatient procedure, observation of patients for 23 to 24 hours is optimal. Observation for 8 hours or less risks missing > or = 20% of complications.

Adult↗
PubMed1996

Reproducibility of studies of peritoneal dialysis adequacy.

To assess the variability and reproducibility of dialysis adequacy clearance measurements (weekly Kt/V and weekly creatinine clearance/1.73 m2 BSA) in a given patient, 42 patients underwent three clearance studies in a one week period. The dialysis prescription was kept constant. There were 21 males with a group mean age of 49 +/- 15 years; 37 patients performed CAPD and 5 DAPD; the dialysis prescription was 6 to 12 liters/day; and 17 patients were anuric. To assess test variability within each patient, the coefficient of variation (CV) and the range were determined for each patient's three clearance values, and for the factors that determine those values. These were averaged to determine the mean patient variability (CV and range) of those measurements. The mean patient CV of the weekly Kt/V was 8.1%. The mean patient range of the weekly Kt/V was 0.30. Of the determinants of total Kt/V, the greatest variability (GV) existed in residual renal urea clearance at 35.4%, with moderate variability seen for peritoneal dialysis urea clearance at 7.0%, which was more a function of variability in D/P urea (CV = 6.3%) than variability in drain volume (CV = 4.1%). There was little variability in V (CV = 0.6%). Similar results were seen for the variability in weekly creatinine clearance measurements. We found that the day-to-day reproducibility of Kt/V measurements is limited, especially in patients with residual renal function, although day-to-day variability in D/P urea also affects Kt/V reproducibility in all patients. Values that fall into the borderline "adequate" range may need to be repeated when considering a patient's dialysis prescription. In addition, research that involves the measurement of Kt/V should utilize more than one collection to increase the reliability of those measurements.

Adult↗
PubMed1996

Long-term outcome in systemic lupus erythematosus membranous glomerulonephritis. Lupus Nephritis Collaborative Study Group.

The pathology of membranous glomerulonephritis (MGN) in patients with systemic lupus erythematosus (SLE) may be complicated by superimposed glomerular inflammation and/or necrosis. This retrospective study examined whether various histologic patterns of glomerulonephritis (GN) seen on renal biopsy impact upon the prognosis of these patients. Clinical parameters at the time of biopsy were also studied, to determine which might serve as risk factors associated with renal and patient outcome. On the basis of renal biopsy findings, patients were stratified into three pathological study groups by using the World Health Organization (WHO) classification (11). Thirty-six patients had "pure' SLE MGN without (WHO Va) or with (WHO Vb) mesangial hypercellularity. Fifteen patients had SLE MGN with segmental endocapillary proliferation and/or necrosis in < 50% of glomeruli (WHO Vc < 50%). Twenty-eight patients had SLE MGN with endocapillary proliferation and/or necrosis in > or = 50% of glomeruli (MGN with segmental proliferation and/or necrosis in > 50%, WHO Vc > or = 50%, or MGN with superimposed diffuse endocapillary proliferation, WHO Vd). There were no significant differences in sex, age, or race among patients in the three study groups. There was a trend for increasing serum creatinine concentration, urine protein excretion, and diastolic blood pressure, and decreasing the third component of serum complement (C3) to be associated with increasing glomerular inflammation, and these differences were significant when Vc > or = 50% and Vd was compared with Va and Vb (P < 0.05). The 5- and 10-yr actuarial survival rates without reaching the study outcomes of death or renal replacement therapy for the three study groups were 86, 72, and 49% and 72, 48, and 20% respectively, and the differences between Va and Vb and Vc > 50% and Vd were significant (P < 0.05). SLE MGN has a heterogeneous course and outcome, and this variability is related to the extent and degree of glomerulonephritis seen on renal biopsy. The only clinical factor with an independent risk of reaching a study outcome was elevation of the initial serum creatinine concentration (Cox regression analysis). This predictive value appears to apply only to patients with the most severe forms of glomerulonephritis, suggesting that they may have a different natural history and/or a response to therapy than SLE MGN with less widespread glomerular inflammation and/or necrosis.

Biopsy↗