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Background and objectives Staphylococcus infection–associated GN (SAGN) is a well recognized disease entity, particularly because of the frequent IgA-dominant glomerular immunoglobulin staining on kidney biopsy. Biopsy features can resemble two other disease entities – primary IgA nephropathy and Henoch-Schonlein purpura nephritis – posing a diagnostic pitfall. This is clinically relevant because of the crucial difference in the therapeutic approach. The diagnosis of SAGN is further complicated by the variability in the degree of glomerular IgA (and C3) staining, the extent of electron dense immune-type deposits, and positive ANCA serology in some patients. Design, setting, participants, & measurements We performed a thorough histopathologic review of our single-center cohort of 78 culture-proven SAGN biopsies to assess the spectrum of IgA staining, prevalence of ANCA serology, prevalence of subepithelial “humps,” and other histologic features to distinguish from primary IgA nephropathy. Results Among the 78 SAGN biopsies, IgA staining was trace in 25%, mild in 19%, moderate in 44%, and strong in 12% of the cases. C3 was frequently moderate-to-strong but was trace in 14% of the biopsies. Concomitantly trace IgA, IgG, and C3 (pauci-immune pattern) was seen in 13%. Crescents were present in 35% of the SAGN biopsies. Out of 41 patients tested for ANCA, nine (22%) were positive, including patients with endocarditis and other infections. Subepithelial humps were identified in only 31% of the SAGN biopsies. Conclusions SAGN biopsies show marked variability in IgA immunofluorescence staining and low frequency of subepithelial humps compared with poststreptococcal GN. Occasional ANCA positivity is present in cases of SAGN, even in infections other than endocarditis. Therefore, biopsy diagnosis can be difficult particularly when clinical symptoms of infection are subtle. Both the pathologist and the nephrologist should be aware of these diagnostic pitfalls.

Autoantibodies to complement C1q (anti-C1q) are associated with the diagnosis of lupus nephritis. In this study, we compare anti-C1q IgG with another complement autoantibody, anti-C3b IgG, as a biomarker of lupus nephritis and lupus nephritis flare.Our investigation involved the Ohio SLE Study, a prospective observational cohort of patients with recurrently active lupus who were followed bimonthly. Serum anti-C1q and anti-C3b IgG levels were assessed cross-sectionally by ELISA in 40 normal controls and 114 patients in the Ohio SLE Study (41 nonrenal and 73 lupus nephritis) at study entry, and longitudinally in a subset of patients in the Ohio SLE Study with anti-C1q-positive lupus nephritis in samples collected every 2 months for 8 months leading up to lupus nephritis flare (n=16 patients).In the cross-sectional analysis, compared with anti-C1q IgG, anti-C3b IgG was less sensitive (36% versus 63%) but more specific (98% versus 71%) for lupus nephritis. Only anti-C3b IgG was associated with patients with lupus nephritis who experienced at least one lupus nephritis flare during the Ohio SLE Study period (P0.01). In the longitudinal analysis, circulating levels of anti-C1q IgG increased at the time of lupus nephritis flare only in patients who were anti-C3b positive (P=0.02), with significant increases occurring from 6 (38% increase) and 4 months (41% increase) before flare. Anti-C3b IgG levels also trended up at lupus nephritis flare, although the change did not reach statistical significance (P=0.07). Neither autoantibody increased 2 months before flare.Although not as prevalent as anti-C1q IgG, anti-C3b IgG showed nearly complete specificity for lupus nephritis. The presence of anti-C3b IgG identified patients with lupus nephritis who were prone to flare and in whom serial measurements of markers associated with complement, such as anti-C1q IgG, may be useful to monitor lupus nephritis activity.

Recent data suggest that nonlinear GFR trajectories are common among patients with CKD, but the modifiable risk factors underlying these changes in CKD progression rate are unknown. Analyses relating baseline risk factors to subsequent GFR decline are suboptimal because these relationships often attenuate as follow-up time increases and these analyses do not account for temporal changes in risk factors. We identified 74 participants in the African American Study of Kidney Disease and Hypertension who had both a period of rapid GFR decline and an extended period of stability during a follow-up period of ≥12 years. We performed a within-patient comparison of time-varying risk factors measured during the periods of GFR decline and stability and identified several risk factors associated with faster GFR decline: more hospitalization episodes and hospitalization days per year; higher BP, serum phosphorus, and urine protein-to-creatinine ratio; lower serum albumin and urine sodium-to-potassium ratio; slower rate of decline of serum urea nitrogen, serum creatinine, serum uric acid, and serum phosphorus; and faster rate of decline of serum hematocrit and serum bicarbonate. By allowing each patient to serve as his or her own control, this novel, within-patient analytic approach holds considerable promise as a means to identify time-varying risk factors associated with stabilization of GFR or acceleration of GFR decline.

Renal flares are common in lupus nephritis. The impact of flares on the development of CKD in lupus nephritis was examined.A retrospective analysis of prospectively collected data from the Ohio Systemic Lupus Erythematosus (SLE) Study was conducted to determine if renal flares predispose to new CKD or progression of preexisting CKD. Patients in the Ohio SLE Study were followed from 2001 to 2009, with a median follow-up of 6 years. For this analysis, patients with biopsy-proven lupus nephritis and at least 3 years of follow-up were included (n=56). Frequency and duration of renal flares were compared between patients who never developed CKD (n=29) and patients who developed new CKD (n=12) and between patients with preexisting but stable CKD (n=7) and patients who progressed (n=8). Groups were also combined into good (no CKD and stable CKD) or poor (new CKD and progressive CKD) for analysis.The new CKD group had more renal flares per year compared with the no CKD group (median=0.56 flares/yr [range=0-2] versus median=0 flares/yr [range=0-1.4]; P0.001). Additionally, the poor outcome group had more renal flares per year compared with the good outcome group (median=0.50 flares/yr [range=0-2] versus median=0 flares/yr [range=0-1.4]; P0.001). New or progressive CKD was not preferentially associated with nephritic compared with proteinuric renal flares. Logistic regression showed that spending more than 30% of time in renal flare (odds ratio, 20; 95% confidence interval, 4.6 to 91.3; P0.001) and age35 years (odds ratio, 69; 95% confidence interval, 6.3 to 753.6; P0.001) were independent predictors of the combined end point of developing new or progressive CKD. All four subjects over 35 years of age that spent over 30% of time in renal flare had a poor outcome.In patients with lupus nephritis, the relative duration of renal flare is an independent predictor of incident and progressive CKD.

Bioimpedance spectroscopy (BIS) technology to assess clinical fluid status has been around for more than two decades. In patients with CKD, BIS has not created much of a splash until just recently ([1][1],[2][2]). The most recent BIS splash is in this issue of CJASN ([3][3]). Here, Tsai et al. ([3][

Summary Severe lupus nephritis is an aggressive disease that requires an aggressive approach to treatment. Recent randomized clinical trials showed that mycophenolate mofetil compared favorably with cyclophosphamide (traditional approach) for remission induction. Consequently, mycophenolate mofetil is now commonly recommended as first-line therapy. Nevertheless, the role of mycophenolate mofetil in treating severe lupus nephritis is unclear, because such patients were excluded from these trials. With this limitation as background, this work addresses the question of mycophenolate mofetil for induction therapy for severe lupus nephritis. We performed a systematic review of the outcomes of treating severe lupus nephritis with mycophenolate mofetil or cyclophosphamide. Because no studies directly addressed this question, these data were extracted from the published literature or obtained by personal communications from investigators. There is no universally accepted definition, and therefore, severe lupus nephritis was arbitrarily defined by renal histology, resistance to therapy, or level of kidney function at presentation. For each trial analyzed, we determined the partial and complete remission rates. Long-term outcomes were compared when available. The pooled results suggest that mycophenolate mofetil and cyclophosphamide are equally effective in inducing remission of severe lupus nephritis. However, relapse rates and risk of developing ESRD were higher for mycophenolate mofetil compared with cyclophosphamide. In conclusion, in the short term, mycophenolatemofetilandcyclophosphamideareaboutequalininducingremission.However,long-termoutcomes suggest better preservation of kidney function and fewer relapses with cyclophosphamide therapy. Therefore, mycophenolate mofetil should not yet be considered the induction drug of choice for severe lupus nephritis. Clin J Am Soc Nephrol 8: ccc–ccc, 2013. doi: 10.2215/CJN.03290412

Background and objectives: In our center, systemic lupus erythematosus nephritis is routinely treated with an oral cyclophosphamide (POCY) regimen. POCY is easy to administer and less expensive than intravenous cyclophosphamide (IVCY) as it is currently used in the United States; however, the use of POCY has declined in favor of IVCY. Our experience with POCY suggests that it is well tolerated and consistently associated with good long-term outcomes. Here we report this experience to build a case for maintaining POCY as a therapeutic option in lupus nephritis. Design, setting, participants, & measurements: This is a single-center, retrospective analysis of the outcome of 46 patients who had systemic lupus erythematosus with nephritis and were treated with POCY between 1995 and 2006. POCY was given for 2 to 4 mo at a dosage of 1.0 to 1.5 mg/kg ideal body weight. After completing POCY, the patients received either azathioprine or mycophenolate mofetil. Results: Median follow-up was 23.5 mo, and median duration of POCY was 4 mo (range 1 to 16 mo). Durable complete or partial remission of proteinuria was achieved in 32 (70%) patients, whereas 5 (11%) progressed to ESRD. Outcomes were comparable in black and white individuals. Adverse effects occurred in fewer than 10% of the cohort, and only four patients discontinued POCY. Conclusions: These results suggest that sequential therapy of POCY followed by azathioprine or mycophenolate mofetil is comparable to IVCY regimens but that efficacy may not be affected by race.

The association of methicillin-resistant Staphylococcus aureus (MRSA) infection with glomerulonephritis (GN) has been well documented in Japan but not in North America. Recently, eight renal biopsies with IgA-predominant or -codominant GN from eight patients with underlying staphylococcal infection, but without endocarditis, were observed at a single institution in a 12-mo period. Renal biopsies were worked up by routinely used methodologies. Eight cases of primary IgA nephropathy were used as controls. Five patients had MRSA infection, one had methicillin-resistant S. epidermidis (MRSE) infection, and two had methicillin-sensitive S. aureus infection. Four patients became infected after surgery; two patients were diabetic and had infected leg ulcers. All patients developed acute renal failure, with active urine sediment and severe proteinuria. Most renal biopsies showed only mild glomerular hypercellularity. Two biopsies had prominent mesangial and intracapillary hypercellularity; one of them (the MRSE-associated case) had large glomerular hyalin thrombi. This patient also had a positive cryoglobulin test. Rare glomerular hyalin thrombi were noted in two other cases. Immunofluorescence showed IgA pre- or codominance in all biopsies. Electron microscopy revealed mesangial deposits in all cases. Five biopsies had rare glomerular capillary deposits as well. In the MRSE-associated GN, large subendothelial electron-dense deposits were present. These cases demonstrate that staphylococcal (especially MRSA) infection-associated GN occurs in the US as well, and a rising incidence is possible. It is important to differentiate a Staphylococcus infection-associated GN from primary IgA nephropathy to avoid erroneous treatment with immunosuppressive medications.

Controlled clinical trials in renal transplantation have demonstrated that mycophenolate mofetil is well tolerated and has lower renal transplant rejection rates than azathioprine regimens. This study reports on the clinical experiences at two institutions with mycophenolate mofetil (MMF) for severe lupus nephritis. Twelve patients with relapsing or resistant nephritis previously treated with cyclophosphamide therapy and one patient who refused cyclophosphamide as initial therapy for diffuse proliferative nephritis but accepted MMF were included. During combined MMF/prednisone therapy, serum creatinine values remained normal or declined from elevated values: mean change in serum creatinine was -0.26+/-0.46 microM/L, P = 0.039. Proteinuria significantly decreased: mean change in urine protein-to-creatinine ratios was -2.53+/-3.76, P = 0.039. Decreased serum complement component C3 and elevated anti-double-stranded DNA antibody levels at baseline improved in some, but not all, patients. The mean initial dose of MMF was 0.92 g/d (range, 0.5 to 2 g/d). The mean duration of therapy was 12.9 mo (range, 3 to 24 mo). Adverse events included herpes simplex stomatitis associated with severe leukopenia (n = 1), asymptomatic leukopenia (n = 2), nausea/ diarrhea (n = 2), thinning of scalp hair (n = 1), pancreatitis (n = 1), and pneumonia without leukopenia (n = 1). Recurrence of the pancreatitis led to discontinuation of MMF in this patient; all other adverse events resolved with dose reduction. It is concluded that MMF is well tolerated and has possible efficacy in controlling major renal manifestations of systemic lupus erythematosus. Controlled clinical trials are needed to define the role of MMF in the management of lupus nephritis.

Patients with chronic kidney failure commonly are advised to maintain a generous fluid intake. The reason that physicians tend to recommend such an increased fluid intake is difficult to understand. A scientific basis does not exist. To the modern nephrologist, this element of the therapeutic armamentarium seems long to be outdated; however, it was once recommended by authorities (1) and is still being advocated by primary care physicians. “My wife forgot to ask whether it is really necessary to keep a fluid intake of 4.5 L daily. This was the advice of her primary care physician. Perhaps 3 L would be better for her BP and sufficient for her kidney.” The husband of the patient raised this question at the end of her consultation visit at our University Hospital Clinic. The patient was seen for a second opinion regarding the management of her chronic kidney disease (CKD) manifested by a serum creatinine of 3.0 mg/dl and non-nephrotic proteinuria. The husband, who is an oncologist, was mainly concerned because his wife was losing sleep at night because of her many nocturnal trips to the bathroom. If the oncologist and his wife were an isolated case, then we would not be writing this article. However, over the years, we have encountered numerous such examples in our nephrology consultative practice. We suggest further that the patients who have CKD and complain about the instruction to drink large amounts of fluid may represent only the “tip of the iceberg.” Likely, there are many more patients who have CKD and whom we nephrologists never hear about because they silently accept their watery fate. Without complaint, they follow the advice of their primary care physician, which is reinforced by the lay press (“drink at least 8 glasses of water a day”) and by well-meaning friends who …

An adult man presented severely ill with vasculitis of his lower extremities and with impaired kidney function. After detailed evaluation at a local hospital, a diagnosis of essential type III cryoglobulinemia was made. High-dose steroid and cyclophosphamide therapy was begun. The patient improved dramatically. However, 6 wk later when his steroid dose was reduced to 30 mg daily, vasculitis recurred. Intensifying his immunosuppressive therapy only worsened his condition. He was than transferred to the Ohio State University Medical Center for consideration for plasmapheresis for the presumed essential type III cryoglobulinemia. However, our evaluation showed that he had bacterial endocarditis causing his type III cryoglobulinemia. When immunosuppressive drugs were stopped and antibiotics were begun, his condition resolved completely. This case illustrates the difficulty of identifying infectious causes of cryoglobulinemia and emphasizes that an initial, highly favorable response of vasculitis to immunosuppressive therapy does not exclude an infectious cause for the vasculitis.

Abstract African Americans (blacks) have a disproportionately high incidence of end-stage renal disease due to hypertension. The Modification of Diet in Renal Disease (MDRD) Study found that strict blood pressure control slowed the decline in glomerular filtration rate (GFR) only in the subgroup of patients with proteinuria. The present report compares the effects of blood pressure control in black and white MDRD Study participants. Fifty-three black and 495 white participants with baseline GFRs of 25 to 55 mL/min/1.73 m 2 were randomly assigned to a usual or low mean arterial pressure (MAP) goal of ≤107 or ≤92 mm Hg, respectively. GFR decline was compared between randomized groups and correlated with the level of achieved blood pressure. The mean (±SE) GFR decline over 3 years in the low blood pressure group was 11.8±7.3 mL/min slower than in the usual blood pressure group among blacks ( P =.11) compared with 0.3±1.3 mL/min slower among whites ( P =.81) ( P =.12 between blacks and whites). In both blacks and whites, higher baseline urine protein excretion was associated with a greater beneficial effect of the low MAP goal on GFR decline ( P =.02 for both races). Combining both blood pressure groups and controlling for baseline characteristics, higher follow-up achieved MAP was associated with faster GFR decline in both blacks ( P P =.002), with a sevenfold stronger relationship in blacks ( P 1 g/d). In addition, a lower level of blood pressure control may be even more important in blacks than in whites in slowing the progression of renal disease.

Previous studies have shown that African Americans (blacks) tend to have higher nocturnal blood pressure than European Americans (whites). The study presented here was undertaken to determine whether treatment of hypertension influences nocturnal blood pressure differently in blacks than in whites. To answer this question, this study measured nocturnal blood pressure by ambulatory blood pressure monitoring (ABPM) in treated hypertensive blacks and whites whose daytime blood pressures were comparable. Inclusion criteria for this study were: diagnosis of essential hypertension, absence of renal failure, and documentation of antihypertensive therapy, diabetic status, proteinuria status, and body weight. All of the black patients in our programs who underwent ABPM and met the above criteria were included in this study. White patients were included on the basis of having the same inclusion criteria as blacks and showing, by ABPM, daytime mean arterial pressure (MAP) in the same range as that of the blacks selected for this study. The results of nocturnal blood pressure were unknown to the investigators when the patients were selected for this study. In the blacks (N = 62) and whites (N = 72) selected for study, the mean daytime (0600 to 2200 h) MAP was 107 +/- 1 SE mm Hg for both the black and white cohorts. To assess nocturnal blood pressure, the period from 0100 to 0500 h was chosen because it likely encompassed an interval of sleep, which is associated with the nadir of nocturnal blood pressure. This interval was termed 0100 to 0500 h, "middle night." Mean middle night MAP was 97 +/- 12 mm Hg in blacks versus 90 +/- 14 mm Hg in whites (P < 0.006, unpaired t test). The greater middle night MAP in blacks compared with whites was a result of the higher diastolic pressure in blacks (80 +/- 11 mm Hg) versus whites (75 +/- 11 mm Hg) (P = 0.003). Mean middle night systolic blood pressure was numerically higher in blacks than whites (131 +/- 18 mm Hg versus 128 +/- 17 mm Hg), but this difference did not achieve statistical significance. The higher middle night blood pressure in blacks versus whites could not be explained by differences between the groups in daytime MAP, age, gender, body weight, serum creatinine level, proteinuria, diabetic status, or greater use of short-acting antihypertensive agents in blacks versus whites. It was concluded that when treated hypertensive blacks and whites are matched for the same daytime blood pressure, blacks tend to have significantly higher nocturnal blood pressure than whites. The magnitude of this difference suggests that it could contribute importantly to the greater target-organ damage that is seen in hypertensive blacks compared with hypertensive whites.

The expression of complement receptor Type 1 (CR1, CD35) on erythrocytes (E) is unique to humans and other primates. E-CR1, a C3b/C4b receptor that also acts as cofactor for Factor I, appears to be important in clearing C3/C4-opsonized immune complexes from the circulation, in controlling complement activation in the circulation, and in regulating antibody formation. This study was undertaken to determine whether therapy with recombinant human erythropoietin (rEPO) might increase E-CR1 expression in humans. The rationale is that young erythrocytes express more E-CR1 than old erythrocytes. Thus, conditions that stimulate erythropoiesis should increase E-CR1 expression. The hypothesis that stimulating erythropoiesis by rEPO therapy can increase E-CR1 expression was tested in six anemic chronic hemodialysis (ESRD) patients and five systemic lupus erythematosus (SLE) patients without renal failure. Before the rEPO therapy, three of the SLE patients were anemic and two were not. The ESRD patients were studied before and during 9 or 10 mo of rEPO therapy. The SLE patients were studied before, during, and after 7 mo of rEPO given by sc injection two or three times weekly. It was found that rEPO therapy was associated with a progressive increase in the average number of CR1/E in each of the ESRD patients and in the anemic SLE patients: mean baseline CR1/E was 210 +/- 50 (SE) for the ESRD patients and 125 +/- 35 for the SLE patients.(ABSTRACT TRUNCATED AT 250 WORDS)

This study tested the hypothesis that the rate of antigen entry into the circulation in systemic lupus erythematosus (SLE), a naturally occurring immune complex glomerulonephritis (IC-GN), is slow compared with that of traditional experimental models of IC-GN, in which the antigen is delivered rapidly as a daily iv bolus. This hypothesis was tested by comparing rates of decline of the third component of complement (C3) and of circulating neutrophils (PMN) in SLE patients with active disease with those of cynomolgus monkeys (CYN) undergoing induction of experimental IC-GN by means of a daily bolus infusion of antigen. It has previously been shown that, as antigen enters the circulation and forms circulating IC, C3 levels and circulating PMN decline acutely. Thus, acute changes in these parameters can be surrogates for the rate of antigen entry into the circulation. In the CYN undergoing induction of IC-GN (N = 11), infusion of the antigen (bovine gamma-globulin) over 10 min resulted in acute declines in C3 levels (25 +/- 6.6%; P = 0.0018 and PMN counts (59 +/- 9%; P < 0.0002). In addition, the CYN experienced the onset of acute respiratory distress and hypotension. By contrast, in patients with active SLE (N = 9), C3 and white blood cell counts measured at 24-h intervals did not change significantly, and episodes of acute hypotension or respiratory distress were not observed. In the CYN, the onset of visible vasculitic lesions in the omentum were also documented within minutes of the infusion of bovine gamma-globulin. The rapidity of onset of these vascular lesions suggests that the tempo at which lesions develop in experimental models of IC disease is faster than that of naturally occurring IC diseases. It was concluded that, in naturally occurring IC diseases, antigen probably enters the circulation slowly over prolonged periods of time, rather than as large boluses over short periods of time, as in traditional experimental models of IC-GN. Thus, models of IC-GN involving a daily bolus infusion of antigen may not be clinically relevant, particularly when IC clearing mechanisms are tested, because the efficiency of these mechanisms may be markedly influenced by the rate at which IC form in the circulation.

The distribution of renal blood flow was measured in isolated blood-perfused dog kidneys using radioactive labeled microspheres. The kidneys were perfused at a constant systolic pressure of 140 mm Hg. For the first 50 minutes of perfusion, flow to the outer zones of the renal cortex was 79±2% (SE) of the total renal blood flow, and inner cortical blood flow accounted for 21±2%. With continued perfusion, inner cortical blood flow increased progressively, reaching 34±3% by 150 minutes--a time when renin substrate was depleted in the perfusates. Infusions of the tetradecapeptide renin substrate (5-50 µg/min) reestablished the fractional distribution of renal blood flow observed in the initial 50 minutes of perfusion, i.e., inner cortical blood flow was reduced significantly from 36±2% to 23±4% ( P

We report on 2 renal transplant patients in whom acute urinary retention developed after anogenital herpes infections. In 1 case a reversible bladder motor and sensory neuropathy occurred secondary to herpes simplex virus infections. In the other case a motor paralytic bladder developed secondary to an anogenital varicella-zoster infection. Documentation was by carbon dioxide cystometrography and denervation hypersensitivity testing. Both cases were reversible without alteration of the immunosuppressive regimens.

The acid-base composition of plasma during hypocapneic anesthesia in man has been used to construct a 95 per cent significance band defining the acute steady-state response to reduced carbon dioxide tensions. The physiologic response to acute respiratory alkalosis with carbon dioxide tensions ranging from 15 to 35 mm of mercury falls within a zone approximately 6 nanomoles per liter wide for hydrogen ion activity and 5 mEq per liter wide for bicarbonate concentration. The present data, taken together with previous studies on acute hypercapnia, permit construction of a significance band encompassing carbon dioxide tensions between 15 and 90 mm of mercury; this band may be used as a nomogram for assessing complicating metabolic components in acute respiratory acid-base disorders. Although a value that lies outside the significance band indicates a mixed acid-base disturbance, a value falling within the band does not necessarily denote the presence of an uncomplicated acute respiratory alkalosis. In...