[The origins of the Renal Immunopathology Group of the Italian Society of Nephrology]

This article describes the birth and development of the Renal Immunopathology Group of the Italian Society of Nephrology. It collects the stories of nephrologists and pathologists who, since the early Seventies up to the first decade of this century, devoted their professional lives to the study of renal pathology with a strong personal involvement, characterized by enthusiasm, commitment, ability, strong spirit of cooperation, and friendship. All this enabled the Group to: propose the criteria for a standardized histological and immuno-histological examination of renal biopsies and reporting; produce several multicenter studies, whose results were also published in important international journals; to set up a national registry of renal biopsies; to organize a number of courses, some of which were associated with the publication of monographs, on various renal diseases. This article also traces the history of renal pathology in Italy from the second half of the Sixties - when young Italian nephrologists and pathologists from different institutions moved to French laboratories to learn new techniques to apply to renal biopsies - up to the present days. It also shows us how Italian renal pathology has been an essential tool for the development of the nephrological clinical practice and the advancement of scientific research.

[Parainfectious glomerulonephritis]

Acute postinfectious glomerulonephritis is uncommon in adults especially in developed countries. Streptococcus is the most frequently identified infectious agent in younger patients and staphylococcus in older patients. The most common sites of infection are the upper respiratory tract and skin in younger patients and skin followed by respiratory and urinary tract in older patients. The prognosis is often poor in older patients and in those with an immunocompromised background including diabetes, malignancy, alcoholism, AIDS, or intravenous drug use. Outcome does not seem to correlate with steroid treatment.

Assessment of kidney volume in polycystic kidney disease using magnetic resonance imaging without contrast medium

BACKGROUND/AIMS

Total renal volume (TRV) is an important index to evaluate the progression of autosomal-dominant polycystic kidney disease (ADPKD). TRV has been assessed by manually tracing renal contours from CT or MR scans, often employing contrast medium (CM). We developed a fast and nearly automated technique based on the analysis of MR images acquired without CM injection for TRV quantification.

METHODS

30 ADPKD patients underwent MRI. After the selection of one point inside each kidney for the entire volume, the automatic extraction of kidney contours was performed on each acquired slice; the segmentation procedure was based on region growing and on the application of morphological operators and curvature-based motion. The area inside each contour was calculated and TRV was derived. Volume measurements were validated by comparison with measurements obtained by stereology.

RESULTS

TRV estimated in patients was 768 ± 545 ml (range 161-3,111 ml). The automatic measurements were in excellent correlation with the manual ones (r = 0.99, y = x - 0.7), with a small bias and narrow limits of agreement in both absolute (-5 ± 37 ml) and percentage (-0.6 ± 9.6%) terms.

CONCLUSION

This preliminary study showed the feasibility of a fast and nearly automated method for determining TRV; importantly it does not require the use of potentially nephrotoxic CM.

[Solid tumors and paraneoplastic glomerulonephritis]

Neoplastic diseases can cause renal damage directly or indirectly. Also their treatment can provoke renal damage. The incidence and prevalence of paraneoplastic glomerulonephritis, especially associated with solid tumors, are a matter of debate and the causal link between cancer and glomerular diseases remains unclear. Paraneoplastic glomerulonephritis is a rare occurrence, with a slightly higher prevalence in the elderly. The most common cancer types associated with paraneoplastic glomerular disease are carcinoma of the lung and the gastrointestinal tract. Membranous nephropathy is the most frequent but not the only presentation of paraneoplastic glomerulonephritis. Patients with unexplained nephrotic syndrome, especially if older than 60 years, with membranous nephropathy and/or with their own risk factors for malignancies should be screened for occult cancer at diagnosis and be followed up carefully after the diagnosis. The primary treatment of paraneoplastic glomerulopathy must be aimed at the cancer and immunosuppressive treatment must obviously be avoided.

Isolated microalbuminuria as the first clinical presentation of Fabry disease in an adult heterozygous female

Fabry disease (FD) is a rare X-linked disorder characterized by low or absent activity of the lysosomal enzyme α-glycosidase-A that leads to progressive accumulation of glycosphingolipids in different organs and tissues. Clinical manifestations vary from classic to atypical forms characterized by one prevalent organ involvement, and a renal variant has been described in men but not in women. However, little is known about renal manifestation in females affected by FD. We herein report a case of a 22-year-old female with isolated and persistent microalbuminuria as the only sign of FD. In light of the importance of early recognition and treatment of FD organ damage, this case should call for future studies to determine how to assess organ damage, investigate the existence of a ‘renal variant’ in FD female patients and determine when best to start enzyme replacement therapy (ERT).

Patients with complex arrhythmias during and after haemodialysis suffer from different regimens of potassium removal

BACKGROUND

Although sudden death is one of the most frequent causes of death in haemodialysis (HD) patients, the problem of cardiac arrhythmias, the major cause of these outcomes, has been little discussed.

METHODS

In 30 arrhythmia-prone HD patients, we compared the arrhythmogenic effects of two dialysis techniques differing in dialysate potassium (K) content. Each patient underwent Acetate-Free Biofiltration sessions with constant (2.5 mEq/l) K (AFB) and sessions with decreasing intra-HD K (AFBK), according to a crossover single blind design. Holter ECG recording and plasma electrolyte measurements were performed during each dialysis session.

RESULTS

There was a tendency in the whole sample for arrhythmia appearance in AFBK to be reduced as compared to AFB throughout the 24 hr period, although this reduction was not statistically significant. In the subset of patients sensitive to dialysis as far as arrhythmia onset is concerned, AFBK was systematically less arrhythmogenic than AFB (P < 0.01). The highest difference was achieved around the 14th hour after the end of dialysis, when the premature ventricular contractions in AFB were 3.9 times higher than in AFBK (P < 0.05). Potassium kinetics differed between the two procedures. At the first hour of treatment, the plasma K concentration was lower in AFB than in AFBK (3.67 +/- 0.15 mEq/l in AFB vs 4.06 +/- 0.13 mEq/l in AFBK, P = 0.05).

CONCLUSIONS

Our study shows a greater arrhythmogenic activity with the use of a constant and relatively low K concentration as compared to decreasing K profiling in dialysis-sensitive arrhythmic patients. Smoother K removal may well engender a kind of protective effect.

Prevention of dialysis hypotension episodes using fuzzy logic control system

BACKGROUND

Automatic systems for stabilizing blood pressure (BP) during dialysis are few and only control those variables indirectly related to BP. Due to complex BP regulation under dynamic dialysis conditions, BP itself appears to be the most consistent input parameter for a device addressed to preventing dialysis hypotension (DH).

METHODS

An automatic system (ABPS, automatic blood pressure stabilization) for BP control by fluid removal feedback regulation is implemented on a dialysis machine (Dialog Advanced, Braun). A fuzzy logic (FL) control runs in the system, using instantaneous BP as the input variable governing the ultrafiltration rate (UFR) according to the BP trend. The system is user-friendly and just requires the input of two data: critical BP (individually defined as the possible level of DH risk) and the highest UFR applicable (percentage of the mean UFR). We evaluated this system's capacity to prevent DH in 55 RDT hypotension-prone patients. Sessions with (treatment A) and without (treatment B) ABPS were alternated one-by-one for 30 dialysis sessions per patient (674 with ABPS vs 698 without).

RESULTS

Despite comparable treatment times and UF volumes, severe DH appeared in 8.3% of sessions in treatment A vs 13.8% in treatment B (-39%, P=0.01). Mild DH fell non-significantly (-12.3%). There was a similar percentage of sessions in which the planned body weight loss was not achieved and dialysis time was prolonged.

CONCLUSIONS

In conclusion, FL may be suited to interpreting and controlling the trend of a determined multi-variable parameter like BP. The medical knowledge of the patient and the consequent updating of input parameters depending on the patient's clinical conditions seem to be the main factors for obtaining optimal results.

[Corticosteroid treatment for a first episode of steroid-sensitive nephrotic syndrome (SSNS) in children: guideline from the Italian Society of Nephrology]

BACKGROUND

The current 3rd edition of the Italian Society of Nephrology guidelines has been drawn up to summarize evidence of key intervention issues on the basis of systematic reviews (SR) of randomized trials (RCT) or RCT data only. In the present guideline, evidence of the use of corticosteroid treatment for a first episode of steroid-sensitive nephrotic syndrome (SSNS) in children is presented.

METHODS

SR of RCT and RCT on SSNS therapeutic interventions were identified referring to a Cochrane Library and Renal Health Library search (2005 update). Results. One SR including 15 RCT was available on this topic. Methodological quality of available RCT was suboptimal according to current methodological standards.

RESULTS

In children with a first episode of SSNS, corticosteroids administered for 3 months or more compared with 2 months' administration are associated with a significant reduction in the risk of relapse at 6, 12 and 24 months, and in frequent relapsing rates, even though complications did not seem significantly increased (psychological, ocular, gastrointestinal disorders, hypertension, growth delay, Cushingoid syndrome, infection and osteoporosis) (evidence from SR). 6-month compared to 3-month treatment regimens are associated with a significant reduction in the risk of relapse at 12-24 months (evidence from SR). Increasing steroids cumulative doses are associated with increasing improvements in the risk of relapse (evidence from RCT). The risk of relapse at 12-24 months correlates inversely with duration of treatment (evidence from SR).

CONCLUSION

In SSNS children, current available evidence supports the hypothesis that primary intervention should be a high dose of corticosteroids administered for 3 months or more. Further studies are necessary to test this hypothesis in adult patients.

[Treating lupus nephritis: guideline from the Italian Society of Nephrology]

BACKGROUND

The current 3rd edition of the Italian Society of Nephrology guidelines has been drawn up to summarize evidence of key intervention issues on the basis of systematic reviews (SR) of randomized trials (RCT) or RCT data only. In the present guideline, evidence of lupus nephritis (LN) treatment is presented.

METHODS

SR of RCT and RCT on different therapeutic options for LN were identified referring to a Cochrane Library and Renal Health Library search (2005 update).

RESULTS

One SR of 25 RCT and 6 further RCT were available to address this issue. Methodological quality of available RCT was suboptimal according to current methodological standards. In LN patients, combining cyclophosphamide (CyA) and steroids as induction therapy results in a reduced risk of serum creatinine doubling compared to steroids alone, although there is no evidence of significant survival advantage and risk of ovarian failure was demonstrated (evidence from SR). The association of azathioprine (Aza) and steroids significantly reduces the risk of all-cause mortality compared to steroids alone (evidence from SR). No significant survival advantages from the association of plasma exchange and CyA or Aza are proven (evidence from SR). No significant differences on renal and survival endpoints are demonstrated with different dosing of CyA (evidence from RCT).

CONCLUSION

In LN patients available evidence supports the hypothesis that immunosuppressive agents reduce the risk of all-cause mortality and the risk of progressive renal disease. Further studies are necessary to test new immunosuppressive agents such as mycophenolate mofetil in severe LN patients.

[Therapeutic strategies for membranous nephropathy: guideline from the Italian Society of Nephrology]

BACKGROUND

The current 3rd edition of the Italian Society of Nephrology guidelines has been drawn up to summarize evidence of key intervention issues on the basis of systematic reviews (SR) of randomized trials (RCT) or RCT data only. In the present guideline, evidence of interventions for idiopathic membranous nephropathy (MN) is presented.

METHODS

SR of RCT and RCT on interventions for MN were identified referring to a Cochrane Library and Renal Health Library search (2005 update).

RESULTS

Three SR and 18 RCT were available to address this issue. Methodological quality of available RCT was suboptimal according to current methodological standards. In patients with MN, nephrotic syndrome and normal renal function, methylprednisolone and chlorambucil or cyclophosphamide for 6 months alternately increase the probability of nephritic syndrome remission (evidence from SR) and long-term renal protection (evidence from RCT). Other drugs (ACTH and cyclosporine) are associated with nephrotic syndrome remission, but there is no evidence of significant effects on renal function (evidence from RCT). In patients with impaired renal function, association of corticosteroids and cytotoxic agents is proven to cause a short-term delay of renal damage progression, even though benefits are counterbalanced by complications (evidence from RCT).

CONCLUSION

In patients with MN, nephrotic syndrome and normal renal function, current available evidence supports the hypothesis that primary intervention should be the association of corticosteroids and cytotoxic agents. Secondary therapeutic choices include ACTH and cyclosporine. Further studies are necessary to test new immunosuppressive agents such as mycophenolate mofetil.

[Immunosuppressive and non-immunosuppressive agents for patients with IgA nephropathy: guideline from the Italian Society of Nephrology]

BACKGROUND

The current 3rd edition of the Italian Society of Nephrology guidelines has been drawn up to summarize evidence of key intervention issues on the basis of systematic reviews (SR) of randomized trials (RCT) or RCT data only. In the present guideline, evidence of the use of immunosuppressive and non-immunosuppressive treatments in IgA nephropathy (IgAN) is presented.

METHODS

SR of RCT and RCT on treatment in patients with IgAN were identified referring to a Cochrane Library and Renal Health Library search (2005 update). Quality of SR and RCT was assessed according to current methodological standards.

RESULTS

Two SR of RCT (13 and 3 RCT, respectively), and 18 further RCT were available to address this issue. Methodological quality of available trials was suboptimal. In patients with IgAN and normal or mildly impaired renal function, steroids significantly delay the progression to end stage kidney disease (evidence from SR) and improve proteinuria. Associating steroids and cytotoxic agents (cyclophosphamide followed by oral azathioprine) proves effective in patients with rapidly progressive renal disease (evidence from RCT). Angiotensin converting enzyme inhibitors and angiotensin II receptor blockers significantly improve proteinuria (evidence from RCT), but there are no conclusive data on efficacy on hard patient level endpoints. There are no conclusive data available on the use of a therapy combining these agents.

CONCLUSION

In IgAN patients current evidence supports the hypothesis that immunosuppressive agents delay the progression to end stage renal disease. Further studies are necessary to test this hypothesis in selected patient populations.

Cardiac response to hemodialysis with different cardiovascular tolerance: heart rate variability and QT interval analysis

A therapy-specific worsening of cardiovascular stability during bicarbonate dialysis (BD) with respect to acetate-free biofiltration (AFB) have been previously reported. We further investigated the impact of the 2 therapies on electrocardiographic parameters in order to gain novel insight into the cardiac responses. Holter ECG acquired during hypotension-free sessions (12 BD + 12 AFB) were retrospectively analyzed. R-R intervals were extracted from ECG recordings. An autoregressive spectral technique was used to compute low- and high-frequency (LF and HF) components of heart rate variability (HRV). QT interval duration was measured with a computer-assisted technique and corrected for HR. In BD the LF component of HRV after an initial increase was slowly depressed with respect to AFB (p < 0.05). QT duration showed a significant (p < 0.01) hemodialysis-induced reduction. QT shortening was more pronounced (p < 0.05) in BD than in AFB (-31 vs. -10 ms), even after correction for HR (p < 0.05). Cardiac electrical activity is significantly affected by the hemodialysis technique. The decrease in the LF component of HRV and the QT shortening are coherent with the worse cardiovascular tolerance observed in BD and with the hypothesis of an enhanced production of endogenous nitric oxide.

Predictors of outcome in Henoch-Schönlein nephritis in children and adults

BACKGROUND

Factors predictive of renal outcome were investigated in 219 cases of biopsy-proven Henoch-Schönlein purpura nephritis (HSPN); 83 children and 136 adults enrolled in a national study were followed up for up to 27 years (median, 4.5 years).

METHODS

The criterion for defining disease progression was time elapsed until doubling of baseline creatinine level and until dialysis therapy. Age, sex, data at onset (renal function, proteinuria, hematuria, hypertension, and crescents), and data during follow-up (proteinuria and therapy) were tested as covariates.

RESULTS

Multivariate Cox regression analysis indicated the following parameters as independent prognostic predictors: age (adults versus children, relative risk, 3.57; 95% confidence interval, 1.18 to 10.79; P = 0.024 for creatinine level doubling; relative risk, 14.89; 95% confidence interval, 1.72 to 129.07; P = 0.014 for dialysis therapy), sex (females versus males, relative risk, 5.71; 95% confidence interval, 1.67 to 19.55; P = 0.006 for creatinine level doubling; relative risk, 26.03; 95% confidence interval, 2.64 to 256.73; P = 0.005 for dialysis therapy), and mean proteinuria during follow-up (for each 1 g/d of protein increase, relative risk, 1.77; 95% confidence interval, 1.35 to 2.32; P < 0.001 for creatinine level doubling; relative risk, 1.73; 95% confidence interval, 1.18 to 2.52; P = 0.005 for dialysis therapy). Information for mean proteinuria levels during follow-up increased the sensitivity at logistic regression to 62.5%, with dialysis therapy as the end point. No data detected at diagnosis, including renal function impairment, proteinuria, hypertension, and crescentic nephritis (involving > 50% of glomeruli in only 2.6%), were significantly related to functional decline at multivariate Cox.

CONCLUSION

This analysis indicates that, even more than when decreased renal function, severe proteinuria, hypertension, or crescents are present at onset, the risk for progression of HSPN (greater in adults and females) was associated with increasing mean proteinuria levels during follow-up.

[The Italian Society of Nephrology Guidelines (3rd Edition): principles and methods]

Scientific Societies at both a local and international level are making big effort to prepare their clinical practice guidelines. The Italian Society of Nephrology has already published in two previous editions a series of guidelines relating to various aspects of management and diagnosis of different renal diseases. In this review we present the criteria of the 3(rd) edition of the Italian Society of Nephrology guidelines. This 3(rd) edition of guidelines will be based on the availability of scientific evidence in different areas of nephrology, dialysis and transplantation. Ten key intervention questions have been identified, based on the availability of systematic reviews of randomized trials or individual randomized address them. Systematic reviews and randomized trials are the optimal study design to address intervention questions. These have been summarized based upon rigid methodological criteria and strictly reflect the evidence basis. The different phases of development and publication of the 3(rd) edition of the Italian Society of Nephrology guidelines are presented.

[Census 2004 of the Italian Renal and Dialysis Units. Emilia-Romagna, Toscana]

The 2004 SIN census of the Italian nephrology and dialysis centres showed many interesting data about the epidemiology and the organization in the Regions of Emilia-Romagna (ER) and Tuscany (T). A) Epidemiology: incidence of dialysis patients 169 pmp (patients per million population) in ER, 147 ppm in T; prevalence of dialysis patients 639 pmp and 665 pmp, respectively; prevalence of transplanted patients 325 ppm in ER and 233 pmp in T; gross mortality of dialysis patients 16.3% and 13.4%, respectively; B) Type of vascular access in prevalently dialysis patients: arteriovenous fistula 83% and 78%; central venous catheter 13% and 12%; vascular graft 5% and 9%. C) Structural resources: nephrology beds 44 mp (per million population) and 50 mp; dialysis places 157 and 146 mp. D) Personnel resources : renal physicians 29 and 41 mp; renal nurses 171 and 202 mp ; each renal physician cares for 22 and 16 dialysis patients, and each renal nurse takes care of 3.7 and 3.3 dialysis patients. E) Activity: hospital admissions 1572, 1769 pmp; renal biopsies 115 and 166 pmp.

Electrophysiological Response to Dialysis: The Role of Dialysate Potassium Content and Profiling

The task of dialysis therapy is, amongst other things, to remove excess potassium (K+) from the body. The need to achieve an adequate K+ removal with the risk of cardiac arrhythmias due to sudden intra-extracellular K+ gradient advises the distribution of the removal throughout the dialysis session instead of just in the first half. The aim of the study was to investigate the electrical behavior of two different K+ removal rates on myocardial cells (risk of arrhythmia and ECG alterations). Constant acetate-free biofiltration (AFB) and profiled K+ (decreasing during the treatment) AFB (AFBK) were used in a patient sample to understand, first of all, the effect on premature ventricular contraction (PVC) and on repolarization indices [QT dispersion (QTd) and principal component analysis (PCA)]. The study was divided into two phases: phase 1 was a pilot study to evaluate K+ kinetics and to test the effect on the electrophysiological response of the two procedures. The second phase was set up as an extended cross-over multicenter trial in patient subsets prone to arrhythmias during dialysis. Phase 1: PVC increased during both AFB and AFBK but less in the latter in the middle of dialysis (298 in AFB vs. 200 in AFBK). The PVC/h in a subset of arrhythmic patients was 404 +/- 145 in AFB and 309 +/- 116 in AFBK (p = 0.0028). QT interval (QTc) prolongation was less pronounced in AFBK than in AFB. Phase 2: The PVC again increased in both AFB and AFBK but less in the latter mid-way through dialysis (79 +/- 19 AFB vs. 53 +/- 13 AFBK). Moreover, in the most arrhythmic patients the benefit accruing from the smooth K+ removal rate was more pronounced (103 +/- 19 in AFB vs. 78 +/- 13 in AFBK).

CONCLUSION

It is not the K+ dialysis removal alone that can be destabilizing from an electrophysiological standpoint, but rather its removal dynamics. This is all the more evident in patients with arrhythmias who benefit from the K+ profiling during their dialysis treatment.

Enzyme replacement therapy in Fabry's disease: recent advances and clinical applications

Fabry's disease is a rare X-linked recessive disorder resulting from deficient lysosomal enzyme, alpha-galactosidase A (alpha-Gal A) activity. The deficiency leads to progressive glycosphingolipid globotriaosylceramide (Gb3) accumulation in fluids and tissues, including vascular endothelium, connective tissue, kidney, heart, brain and peripheral nerves. Classic Fabry's disease in hemizygous males has high morbidity and mortality due to end-stage renal disease (ESRD) requiring hemodialysis (HD) or kidney transplantation, myocardial involvement and central nervous system (CNS) complications. Most heterozygous females can also suffer from this severe disease deterioration. Until recently, Fabry's disease management consisted of symptomatic and palliative treatment, but this has changed with the availability of the recombinant human alpha-Gal A enzyme, agalsidase. Two different agalsidase formulations have been obtained: one from human fibroblast (agalsidase alpha), and one from Chinese hamster ovary (CHO) cells (agalsidase beta). Both preparations underwent clinical trials that documented the feasibility, efficacy and safety of the treatment. In addition, several clinical observations have proved that agalsidase reduces the storage of the substrate from several organs and tissues and, consequently, improves signs and symptoms of Fabry's disease. Additional clinical experiences have confirmed the initial clinical trial results, but further studies are needed to evaluate the long-term outcome of enzyme replacement therapy (ERT). We reviewed the clinical trial observations, as well as subsequent clinical experiences with ERT in patients with Fabry's disease.

Enzyme replacement therapy with agalsidase beta in kidney transplant patients with Fabry disease: a pilot study

BACKGROUND

We sought to assess the safety and efficacy of enzyme replacement therapy (ERT) with recombinant human-alpha-galactosidase A (rh-alpha-Gal A) in kidney transplant recipients with Fabry disease, a previously unstudied population.

METHODS

Three male kidney transplant recipients with biochemically, genetically, and histologically confirmed Fabry disease and documented Fabry myocardiopathy received the rh-alpha-Gal A, agalsidase beta, 1 mg/kg of body weight every 2 weeks by intravenous infusion and were monitored biochemically, clinically, and electrocardiographically and echocardiographically for 18 months.

RESULTS

Patients showed biochemical, clinical/functional, and morphologic response to ERT. Plasma globotriaosylceramide decreased 23% to 50%. Extremity pain resolved within 2 months in the patient with this manifestation. On echocardiography, left ventricular mass, end diastolic diameter (EDD), and cardiac contractility, shown by ejection fraction (EF), improved in 2 of the 3 patients receiving essentially all planned infusions. EDD and EF remained basically stable, but cardiac morphologic abnormalities progressed in the other patient, who had a 5-month interruption in ERT after the initial month. Mild mitral insufficiency persisted in all patients, as did atrial fibrillation in the affected individual. After a combined total of 116 infusions, no treatment-related adverse event, intolerance, or seroconversion was seen. Renal function remained stable and the immunosuppression regimen unchanged in all patients.

CONCLUSION

Our pilot study provides preliminary evidence that ERT with agalsidase beta, 1 mg/kg every 2 weeks, is safe and often effective against extra-renal manifestations in kidney transplant patients with Fabry disease. Studies with longer courses of this and higher doses of ERT are merited in this population.

Model-based study of the effects of the hemodialysis technique on the compensatory response to hypovolemia

BACKGROUND

Hemodialysis technique (dialysate composition, filter, convection/diffusion ratio, etc.) can have an impact on the patient's tendency to acute hypotension. We have examined the hypothesis that the dialysis technique affects the hypotension risk by altering the cardiovascular compensatory response to hemodialysis-induced hypovolemia.

METHODS

Twelve hypotension-prone subjects were studied during six sessions of conventional bicarbonate dialysis (BD) and six sessions of acetate-free biofiltration (AFB). Blood volume (BV) control system was used in AFB to provide a BV change equivalent to the BV change observed in BD. The efficacy of reflex compensatory mechanisms was assessed by a model-based computer analysis of the BD and AFB sessions.

RESULTS

BD sessions were complicated by hypotension more frequently than the AFB ones (34/66 BD vs. 18/66 AFB). Hypotension arose about 60 minutes earlier in BD (123 +/- 41 minutes in BD vs. 183 +/- 25 minutes in AFB, P < 0.01), and after a smaller BV reduction (hypotension BV 7.9%+/- 2.0% in BD vs. 10.9%+/- 2.6% in AFB, P < 0.05). Model-based computer analysis of the sessions without hypotension revealed differences in peripheral resistance adaptation (9%+/- 9% BD vs. 19%+/- 7% AFB, P < 0.05) as well as in the stroke volume reduction (19%+/- 8% BD vs. 10%+/- 8% AFB, P < 0.001). Model analysis of sessions with hypotension indicated that compensatory mechanisms were almost inoperative in BD, whereas a residual capacity to control peripheral resistance and cardiac contractility was present in AFB. Model simulations demonstrated that hypotension occurred later in AFB since the residual compensatory capacity in AFB was able to sustain the arterial pressure for larger BV reductions (8.3% BD vs. 11.2% AFB).

CONCLUSION

The increased risk of acute hypotension in BD compared to AFB is caused by a therapy-induced inhibition of reflex compensatory response to hypovolemia.

[Instructions and implementations for percutaneous renal biopsy. Guidelines for the therapy of glomerular nephropaties]

This series of articles on the management of glomerulonephritis (GN) has been prepared by a team of experts in the evidence-based format consistent with peer review of published data. Each author was asked to review the literature for his assigned histological type, with emphasis on therapy and limited to adult studies. The age limit was not considered for minimal change disease and focal segmental glomerulosclerosis, because of the high prevalence of these glomerulopathies in children. The particular treatment recommendations for each type of glomerular disease were graded by each author according to the amount of evidence provided in these reviewed studies. The first two articles concentrate on indications and techniques for kidney biopsy. Each subsequent article focuses on and describes the highest level of evidence supporting the recommendation for therapy in IgA nephropathy (Ig-GN), minimal change nephropathy (MCN) and focal segmental glomerulosclerosis (FSGS), membranous glomerulonephritis (MGN), lupus nephritis, ANCA-associated vasculitis, HCV-associated cryoglobulinaemia and renal involvement in paraproteinemic disorders. The article on IgA nephropathy emphasises the importance of carefully evaluating both clinical and histologic findings before settling on the treatment. The recent, renewed interest in steroids and many immunosuppressive agents is discussed in detail. Recommendations related to the patient's age are also provided. MCN and FSGS are treated together because these forms share similar evidence-based recommendations. For both of these diseases, in fact, the initial treatment approach in children should be prednisone or prednisolone for four to six weeks. The therapeutic response in adults is slower than in children, but adults experience fewer relapses and a more prolonged remission. There is also a discussion on treatment of relapse, frequent relapsing disease and true steroid-resistant disease as well as the role of new immunosuppressive agents. Membranous nephropathy is a frequent cause of nephrotic syndrome in adults and, in one third of these patients, leads to end-stage renal disease. However, the treatment of this form is as yet a matter of discussion. Based on extensive critical review of the literature, the following recommendations are put forward: (a) no treatment in the absence of nephrotic syndrome; (b) patients with heavy proteinuria should receive a 6-month treatment with i.v. methylprednisolone (MP) pulse therapy for three consecutive days followed by oral MP (0.4 mg/kg/day) (months 1, 3, 5) and chlorambucil or cyclophosphamide (months 2, 4, 6); (c) the dosage of chlorambucil or cyclophosphamide should be lowered in older patients; (d) cyclosporine is a second-choice treatment. The treatment of lupus nephritis depends on the histologic class. No specific treatment is usually necessary for class I and IIA. Oral steroids are indicated in patients with class IIb, proteinuria and active systemic disease. Steroids and azathioprine are the treatment of choice for patients with class III and IV, but cyclosporine can be an effective alternative therapy. Cyclophosphamide is more effective than azathioprine when severe acute renal involvement is present. The treatment of ANCA-associated vasculitis depends mainly on clinical presentation, oral prednisone + oral or i.v. cyclophosphamide are generally effective. In the most severe cases, the association of MP pulse therapy with cyclophosphamide is probably more effective. Plasma exchange is probably justified in unresponsive patients. Azathioprine should replace cyclophosphamide during the maintenance therapy. In HCV-associated mixed cryoglobulinemia the treatment also depends on the severity of renal involvement. The treatment for chronic HCV infection involves alpha interferon alone or preferably in combination with ribavirin. Aggressive therapy, including i.v. MP, plasmapheresis and cyclophosphamide is primarily reserved for patients with acute severe disease, as manifested by progressive renal failure, distal necroses requiring amputation, or advanced neuropathy. Uncontrolled studies suggest that this regimen can improve renal function. Renal involvement is a common problem in paraproteinemic disorders that include multiple myeloma, Waldentrom's macroglobulinaemia and monoclonal gammopathy. The most common renal diseases in this setting are cast nephropathy, primary amyloidosis cast nephropathy, primary amyloidosis, and light chain deposition disease that are related to the overproduction of monoclonal immunoglobulin light chains. The approach to therapy varies with the cause of the renal dysfunction. Patients with amyloidosis or light-chain deposition disease are generally treated with chemotherapy, but the most effective therapy for myeloma kidney is prevention by minimising the risk factors that promote light chain filtration and subsequent obstruction by cast formation within the tubules. Chemotherapy or stem cell or bone marrow transplantation to decrease filtered light chain load, prevent volume depletion and maintain high fluid intake to reduce light chain concentration within the tubular lumen are indicated in almost all the patients.

Long-term prognosis of Henoch-Schönlein nephritis in adults and children. Italian Group of Renal Immunopathology Collaborative Study on Henoch-Schönlein purpura

BACKGROUND

The aim of this multicentre collaborative study was to compare the progression of renal disease in children and adults with Henoch-Schönlein purpura (HPS) nephritis selected on the basis of IgA-dominant renal deposits and biopsy material available for review.

METHODS

The analysis was performed in 152 patients (95 adults and 57 children < 16 years old at diagnosis) with a follow-up (> or = 1 year up to 20 years (4.9 +/- 3.4 years in adults and 4.8 +/- 3.9 years in children).

RESULTS

Renal histology and clinical presentation were similar in both age groups: crescents were found in 36% of adults and 34.6% of children (in only 2.7% of adults and 1.9% of children involving > 50% of glomeruli), nephrotic-range proteinuria in 29.5% of adults and 28.1% of children and functional impairment in 24.1% of adults and 36.9% of children. The outcome was similar for both age groups (remission, 32.5% of adults and 31.6% of children; renal function impairment, 31.6% of adults and 24.5% of children). Endstage renal disease was observed in 15.8% of adults and in 7% of children. Renal function survival at 5 years was not significantly different in the two groups (85% in adults and 95% in children) and at 10 years it was approximately 75% in both groups. None of the children died and adult survival was 97% at 5 years. In adults at presentation, renal function impairment (P < 0.02) as well as proteinuria higher than 1.5 g/day (P < 0.02) and hypertension (P < 0.001) were negative prognostic factors. Multivariate analysis stressed the main statistical relevance of proteinuria (relative risk 2.37, P < 0.02). Conversely, in children no definite level of proteinuria, hypertension or other data were found to be associated with poor prognosis.

CONCLUSIONS

Among patients with a clinical presentation which warrants renal biopsy, HSP nephritis has a similar prognosis in children and adults. The evolution is more predictable in adults than in children.

Ethylene-oxide and steam-sterilised polysulfone membrane in dialysis patients with eosinophilia

Eosinophilia and some acute dialysis side-effects, such as itching, flushing and bronchospasm, are often associated with the presence of ethylene oxide (ETO) as dialyzer sterilizing agent. This study evaluated the effects of two different polysulfone (PS) hollow-fiber dialysers sterilized with ETO and steam in 31 chronic dialysis patients with eosinophilia. Clinical symptoms, metabolic and biochemical parameters, complement (C3a and C5a) activation and production were evaluated in each patient dialysed for two months at a time with Cuprophan dialyser, ETO-PS dialyser and steam-PS dialyser. The steam-sterilizer agent does not alter the purifying capacity of the PS membrane which maintains its superiority over Cuprophan in terms of biocompatibility. Using steam-PS, intradialytic eosinophil kinetics seems to improve. In some patients with high serum levels of ETO-specific IgE these levels tend to diminish. Generic intradialytic symptoms do not differ between the two sterilization methods, although some hypersensitivity symptoms during the first dialysis hour are considerably lower in some patients when steam-sterilized PS is used.

Analysis of the factors influencing bicarbonate balance during acetate-free biofiltration

In acetate-free biofiltration (AFB), the physical separation between the base losses and the gains could facilitate the modeling of intradialytic bicarbonate (HCO3) balance. In order to verify this hypothesis, we analyzed in a multicenter study, 126 AFB sessions in which differing parameters were evaluated (dialysis time, blood flow, ultrafiltration, infused HCO3, pre- and post-dialytic HCO3, hematocrit and body wt). Statistical analysis performed with multiple linear regression showed that the post-dialysis HCO3 was significantly dependent (F = 21.68, d.f. 5.95, P < 0.001) directly on the amount of infused HCO3, the level of pre-dialysis HCO3 and the final body weight, and inversely on the dialysis time and the blood flow. HCO3 values predicted by the statistical model correlated well with the observed ones (r = 0.788, P < 0.0001) with a mean absolute difference of 2.138 mEq/liter. This modeling approach allowed us to predict, with a computer-aided procedure, the quantities of HCO3 to be infused to obtain a desired and personalized acidosis correction.

Acute bilateral renal vein thrombosis superimposed on calcified thrombus of the inferior vena cava in a patient with membranous lupus nephritis

We report a case of membranous lupus nephritis with a previous history of long-standing nephrotic syndrome which developed an acute renal failure due to bilateral renal-vein thrombosis superimposed on a calcified thrombus of the inferior vena cava eight years after the diagnosis. The occurrence of acute renal-vein thrombosis is a possible but rarely described complication of systemic lupus erythematosus. The presence of a calcified thrombus of the inferior vena cava has been described in only one adult patient until now. An aggressive thrombolytic therapy with urokinase permitted the fresh thrombus to be dissolved with a marked improvement in renal function.

A randomized trial of methylprednisolone and chlorambucil in idiopathic membranous nephropathy

We conducted a controlled trial to investigate the long-term effects of treatment with methylprednisolone and chlorambucil in patients with idiopathic membranous nephropathy. We have previously reported that after a mean of 31 months, treated patients did better. We now report the results of a longer follow-up. Eighty-one patients with proteinuria (greater than or equal to 3.5 g per day) and biopsy-proved membranous nephropathy were randomly assigned to receive either supportive therapy alone or a six-month course of corticosteroids alternated with chlorambucil (0.2 mg per kilogram of body weight per day) every other month. Methylprednisolone was first given intravenously in three pulses (1 g per day) and was then given orally (0.4 mg per kilogram per day) for 27 days. The patients were followed for 2 to 11 years (median, 5). Two patients in the control group and one in the treatment group died. At the last follow-up visit, 9 of 39 patients assigned to the control group (23 percent) and 28 of 42 patients assigned to the treatment group (67 percent) did not have the nephrotic syndrome. At five years there were more remissions of the nephrotic syndrome in treated patients than in controls (22 of 30 vs. 10 of 25; P = 0.026). Compared with base-line values, the mean reciprocal of the plasma creatinine level declined significantly in the control group (33 percent; P = 0.0002) but not in the treatment group (6 percent; P not significant). Plasma creatinine increased by 50 percent or more in 19 controls (49 percent) and in 4 treated patients (10 percent). We conclude that a six-month course of methylprednisolone and chlorambucil can bring about sustained remission of the nephrotic syndrome and help to preserve renal function in patients with idiopathic membranous nephropathy.

Controlled plasma exchange trial in acute renal failure due to multiple myeloma

We studied 29 patients affected by acute renal failure due to multiple myeloma with Bence-Jones proteinuria greater than 1 g/day to evaluate the effectiveness of plasma exchange in the treatment of severe myeloma nephropathy. Renal failure was severe enough to require dialysis in 24 cases, while the remaining 5 patients showed serum creatinine levels greater than 5 mg/dl. The patients were randomly allocated to Group I (15 patients undergoing plasma exchange together with corticosteroids, cytotoxic drug, hemodialysis only when needed) or to Group II (14 patients undergoing peritoneal dialysis together with corticosteroids and cytotoxic drug). In Group I Bence-Jones proteinuria decreased dramatically (P less than 0.01) with a significant increase in urine output (P less than 0.001), while Group II presented a slight reduction in Bence-Jones proteinuria without a significant increase in daily diuresis. Thirteen out the 15 Group I patients recovered renal function reaching serum creatinine levels less than or equal to 2.5 mg/dl in most cases. Only two patients in Group II improved renal failure well enough to stop dialysis. The one-year survival rate was significantly higher in Group I (66%) than in Group II (28%, P less than 0.01). We conclude that plasma exchange associated to chemotherapy rapidly removes large amounts of light chains, improves both renal function and long-term survival expectancies.

Prognostic value of T lymphocyte subset ratio in idiopathic membranous nephropathy

The behavior of T lymphocyte subsets was studied in 39 Italian patients with nephrotic syndrome due to idiopathic membranous nephropathy. They took part in a long-term prospective and randomized therapeutic trial based on the 6-month administration of methylprednisolone and chlorambucil. The lymphocyte subsets were evaluated by monoclonal antibodies at the beginning of the trial and at the end of the follow-up period in 23 treated and in 16 untreated patients. Our data seem to suggest that a higher helper-inducer/suppressor-cytotoxic cell ratio before therapy may be a good prognostic index of improved proteinuria. Moreover, the therapeutic schedule does not seem to induce a long-lasting abnormality in cellular immunity.

Long-term prognosis of diffuse lupus nephritis

The follow-up of 43 patients with diffuse proliferative lupus nephritis is reported. After histological diagnosis, all patients were treated with 3 intravenous high-dose methylprednisolone pulses and then with low-dose oral steroids and 31 with cytotoxic drugs. Renal and extra-renal exacerbations were also treated with intravenous high-dose steroids. Patients were followed for 1 to 13 years. At 10 years the patient survival rate was 87% and the kidney survival rate was 79%. If 3 extra-renal deaths are excluded, the actuarial 10-year kidney survival rate is 91%. At present, 21 patients do not show any renal abnormalities, 13 patients have normal plasma creatinine but proteinuria, 3 patients have stable renal function impairment, 2 patients have worsening of their renal function, 1 is on regular dialysis. The other 3 patients died (from cardiac failure, cerebral hemorrhage and a car accident). The incidence of flare-ups was low (0.1 episodes per year). Severe side effects were rare in this series. It is concluded that the long-term prognosis of diffuse lupus nephritis is becoming considerably better. Therapy based on a short course of intravenous high-dose methylprednisolone and on a maintenance regimen with low doses of steroid and cytotoxic agents can contribute to preserving renal function while avoiding severe side effects.

Renal histological lesions and clinical syndromes in multiple myeloma. Renal Immunopathology Group

This retrospective multicenter study, based on 42 patients affected by renal damage due to multiple myeloma, analyzes the renal biopsy results, the clinical data at the time of biopsy and the subsequent renal outcome in order to clarify the correlations existing between clinical and histological changes. Plasmocytoma components were Bence Jones alone in 55% of the patients and light-chain excretion was present in over 90%. Rapidly progressive renal failure was the most frequent clinical presentation (27 cases). The histological lesions directly attributable to multiple myeloma were subdivided into 3 basic categories: related to light-chains, direct tumor involvement of renal parenchyma and attributable to systemic effects of neoplastic disease. Light-chains seemed to cause renal lesions in 59.4% of the cases. Myeloma cast nephropathy was the prominent bioptic diagnosis established (20 cases). Among the clinical, laboratory and histological parameters studied, only the degree of tubular-interstitial damage was significantly correlated to the renal outcome in the 32 patients who had an adequately documented follow-up period.

Clinical and morphologic evolution of idiopathic membranous nephropathy

Twenty-five adult patients with idiopathic membranous nephropathy (IMN) and nephrotic syndrome (NS) who had participated at a long-term randomized trial with steroid and chlorambucil for six months, underwent repeated renal biopsies. The mean interval between pretreatment and the second biopsy was 41 months. Five evolutionary morphologic changes were adopted. Extensive normalization of the basement membrane (stage V) was observed in 6 of the 9 patients with complete and sustained remission. Only patients in stages I or II at admission seemed to get to reparation stage V. Persistence of NS or a partial remission was usually associated to the progression of the capillary wall lesion to stage III or IV. Our treatment schedule significantly increased the likelihood of getting to the reparation stage V.

Cell interposition in glomerular capillary walls in cryoglobulinemic glomerulonephritis (CRYGN). Ultrastructural investigation of 23 cases

The present report describes ultrastructural findings on twenty-three cases of CRYGN showing membranoproliferative pattern under light microscopy. Attention was paid to the presence of double contoured peripheral basement membranes and to the characteristics of the interposed cells. The latter, according to the well known characteristics of membranoproliferative GN, are thought to be mesangial in nature. In fact, mesangial cells were found in 8 cases only, always associated with monocytes. Only monocytes were recorded in 12 cases, whereas in other 3 cases double contours were not connected to cell interposition. Despite similarities under light microscopy, CRYGN is therefore rather different from idiopathic membranoproliferative GN because of the prevalence of exudative changes, mainly due to monocyte infiltration, over proliferative lesions.

B and T cell abnormalities in patients with primary IgA nephropathy

The in vitro function of B and T cells was studied in 16 patients with primary IgA nephropathy (PIgA-N). The distribution of OKT3+ cells (total peripheral T cells) and of regulatory T cell subsets (helper OKT4+ and cytotoxic/suppressor OKT8+ cells) was evaluated and a testing for 47 HLA-A, B, C, DR, and DQ antigens was carried out in the 16. B lymphocyte IgA production, after stimulation by pokeweed mitogen in the presence of T cells from normal donors treated with mitomycin C, was significantly greater in patients than in controls. T lymphocytes from patients with PIgA-N were more efficient than T cells from controls in providing IgA specific helper activity for normal B cells. The analysis of the individual data showed that the overactivity of B cells and the T cell operational dysfunction was present in about 50% of the patients and did not correlate. No numerical imbalance between T lymphocyte subsets nor any association between lymphocyte behavior, HLA antigen distribution, and a number of clinical, laboratory, and immunohistological findings was observed. Our data, therefore, suggest that PIgA-N is an immunologically heterogeneous disease and that an IgA-specific B cell overactivity and/or overall IgA-specific T cell helper activity may be present in some patients.

Plasma exchange therapy in rapidly progressive renal failure due to multiple myeloma

Nineteen patients with severe renal failure due to multiple myeloma and with Bence Jones proteinuria greater than 1 gm/day were randomly assigned to group I or group II. Corticosteroids and cytotoxic drugs were given to all cases. The 9 patients of group I were also treated by peritoneal dialysis and the 10 patients of group II by plasma exchange and hemodialysis. Only 1 patient of group I, who was not oliguric at the onset, showed partial recovery from renal failure after 3 months of therapy, while 9 patients of group II (3 of whom were oliguric) had significant decrease in Bence Jones proteinuria and rapid improvement from the renal failure. In our experience, plasma exchange is more effective than peritoneal dialysis for reducing Bence Jones proteinuria and recovering from renal failure, even when there is oliguria.

Controlled trial of methylprednisolone and chlorambucil in idiopathic membranous nephropathy

Sixty-seven adults with idiopathic membranous nephropathy and the nephrotic syndrome were randomly assigned to symptomatic treatment only or to a six-month course of methylprednisolone alternated with chlorambucil every other month. Patients were followed for one to seven years. At the end of follow-up (mean of 31.4 +/- 18.2 months for the treated group and 37.0 +/- 22.0 for the control group) 23 of 32 treated patients were in complete or partial remission, as compared with 9 of 30 control patients (P = 0.001). Twelve of the treated patients were in complete remission, as compared with only two of the controls. In the treated group there were no changes in renal function during follow-up, whereas in the control group the reciprocal of the plasma creatinin level, which is proportional to the creatinine clearance, decreased significantly (P = 0.00017) after two years of follow-up. Side effects were minimal in all treated patients except two, who were dropped from the study because of peptic ulcer and gastric intolerance to chlorambucil. We conclude that steroid and chlorambucil treatment for six months favors remission of the nephrotic syndrome in adults with idiopathic membranous nephropathy and can preserve renal function for at least some years.

Focal glomerulosclerosis in patients with unilateral nephrectomy

To investigate whether proteinuria and focal glomerulosclerosis (FSG) might develop in humans as well as in experimental models following a reduction in renal mass, we performed a retrospective study of 24 patients previously nephrectomized for unilateral renal disease. None of the patients presented signs of systemic diseases. Alport syndrome, essential hypertension, reflux nephropathy, and other abnormalities on intravenous pyelography. At the time of the first observation seven patients had pathological proteinuria (group 1) while 17 presented a normal protein excretion (group 2). All patients in group 1 and only 4 of 17 in group 2 were male. No other significant differences were found between the two groups. The median age at nephrectomy of the proteinuric patients was 22.3 years, and proteinuria developed after a mean period of 12.2 years. A renal biopsy was performed in four patients and showed a constant pattern of FSG. After a mean follow-up period of 7.3 years from the onset, proteinuria remains unchanged and renal function is well preserved in all the patients. In conclusion our series suggests that also in humans proteinuria and FSG might appear in solitary kidneys due to nephrectomy. This glomerular damage may result from the association of glomerular overload with other unidentified factors.

[Helper or suppressor activity of T lymphocytes in patients with Berger's disease]

We have studied the immunological aspects in ten cases of Berger disease. Interaction between B and T lymphocytes were investigated to define help or suppressor activity 6 cases have demonstrated help activity, while suppressor activity was observed in two cases.

Controlled trial of monthly alternated courses of steroid and chlorambucil for idiopathic membranous nephropathy

Forty-nine patients with membranous nephropathy (MN) and nephrotic syndrome (NS) were randomly allocated to supportive or specific therapy. The latter consisted of steroids or chlorambucil given in alternate months for a cumulative period of six months. Three patients in the experimental group were dropped from the study because of therapy related side-effects. At the end of follow-up there were significantly more patients in complete or partial remission in the experimental group than in the controls. The mean serum creatinine did not change in treated patients, but it significantly increased in controls.

T cell subset alterations in idiopathic glomerulonephritis

Peripheral blood lymphocytes from 15 healthy controls and 59 patients with idiopathic glomerulonephritis were studied to determine whether an imbalance exists among human T cell subsets in these diseases. Twenty of the patients studied had a minimal change nephropathy (10 with nephrotic syndrome and 10 in sustained remission); 27 had a membranous glomerulonephritis (12 with nephrotic syndrome, six with isolated proteinuria and nine in complete remission); 12 patients had an IgA glomerulonephritis with heamaturia and mild proteinuria. Monoclonal antibodies directed at human T lymphocyte subsets termed OKT3, OKT4 and OKT8 were used in an indirect immunofluorescence assay in all cases. Patients with minimal change nephropathy, with or without nephrotic syndrome and patients with IgA glomerulonephritis showed mean values of OKT3⁺ cells (total peripheral T cells), helper OKT4⁺ cells, suppressor OKT8⁺ cells and OKT4⁺/OKT8⁺ cell ratio, in the normal range. Only the group of patients with membranous glomerulonephritis and nephrotic syndrome presented a mean OKT4⁺/OKT8⁺ ratio greater than the normal group (percentages: 2·43±0·3 vs 1·6±0·1 s.e.m.; P<0·02). This increased ratio was due to a reduction in the OKT8⁺ cell subset compared to the healthy subjects (percentages: 27·6±2·9 vs 36·8±1·4 s.e.m.; P<0·01). Our data shows that the functional lymphocyte disorders previously described in minimal change nephropathy and IgA glomerulonephritis are not due to a numerical imbalance of lymphocyte subsets. Such an imbalance of lymphocyte subsets was specifically observed in membranous glomerulonephritis with nephrotic syndrome. The true significance of this finding has to be clarified by longitudinal studies and functional tests.