The steroid-sparing effects of a mycophenolate mofetil-based regimen in the management of immunoglobulin A nephropathy in patients with histologically active lesions: A comparison with a control cohort receiving conventional therapy

INTRODUCTION

While the use of different immunosuppressants has been investigated in immunoglobulin A nephropathy, further investigation is needed to assess the effect of a regimen of mycophenolate mofetil combined with a short course of glucocorticosteroids in the subset of patients with histologically active features. We compared the efficacy and safety of a combined regimen of mycophenolate mofetil and glucocorticosteroids to a conventional regimen of glucocorticosteroids alone in patients with immunoglobulin A nephropathy who have active lesions and major urinary abnormalities.

METHODS

This retrospective study involved 30 immunoglobulin A nephropathy patients with active histological lesions, 15 of whom were treated with both mycophenolate mofetil 2 g/day for 6 months and 3 pulses of 15 mg/kg methylprednisolone, followed by a short tapering schedule of oral prednisone. The control group was made up of the remaining 15 clinically- and histologically-matched patients treated with glucocorticosteroids alone according to a validated schedule, i.e., 1 g of methylprednisolone given intravenously for 3 consecutive days, followed by oral prednisone 0.5 mg/kg every other day for 6 months. At diagnosis, all patients had urinary protein excretion > 1 g/24 h and microscopic hematuria.

RESULTS

At the end of the first year of follow-up (30 patients) and after 5 years (17 patients), there were no differences between the two groups in terms of urinary abnormalities and functional parameters. Both regimens achieved a statistically significant decrease in 24-h urinary protein excretion (p < 0.001) and a reduction of microscopic hematuria. However, the mycophenolate mofetil-based regimen allowed a cumulative sparing dose of 6 g of glucocorticosteroids.

CONCLUSION

In this single center study on immunoglobulin A nephropathy patients with active lesions and major urinary abnormalities and at increased risk of glucocorticosteroid-related complications, a mycophenolate mofetil-based regimen demonstrated similar outcomes in terms of complete response and relapse (at 1 and 5 years) compared to a conventional glucocorticosteroid-based protocol, while achieving a consistent reduction of glucocorticosteroid cumulative dose.

Semi-selective plasma filtration applied to the treatment of acquired thrombotic thrombocytopenic purpura following bnt162b2 administration

Following the widespread use of anti SARS-CoV-2 vaccines, there have been reports of thrombocytopenia developing after the administration of different types of vaccine. We report a case of a 63-year-old male who developed neurological symptoms after receiving the second dose of the bnt162b2 vaccine. Blood tests performed upon admission to the Emergency Department revealed severe thrombocytopenia and microangiopathic hemolytic anemia. ADAMTS13 activity was undetectable and antibody titer was high. Due to the rapid neurological deterioration, steroid therapy with prednisone was started at an initial dose of 1 mg/kg/day. Rituximab therapy was started to prevent the formation of new antibodies. Given the slow response to this therapy, we added Caplacizumab, (a monoclonal antibody anti-Von Willebrand factor) in order to inhibit platelet hyperaggregation, combined with standard plasma exchange. The patient experienced repeated episodes of intolerance to fresh frozen plasma (FFP). Switching from plasma exchange to plasma filtration, remission was attained in this unusual case of vaccine-related thrombocytopenia with microangiopathic hemolytic anemia.

Renal involvement as a unique manifestation of hemophagocytic syndrome

Renal-limited hemophagocytic syndrome (HPS) is a rare clinical setting characterized by abnormal activation of the immune system. Fever associated with pancytopenia, hepatosplenomegaly with liver dysfunction, and hypofibrinogenemia are usually observed in HPS. From a histological level, the presence of non-malignant macrophages infiltrating bone marrow and organs represents the hallmark of this condition. Non-malignant macrophages are associated with phagocytizing activities involving other blood cells. While primary HPS is usually associated with inherited dysregulation of the immune system, secondary HPS usually occurs in the context of infection or is linked to a neoplastic process. Clinical presentation varies and can potentially lead to life-threatening settings. While renal involvement has frequently been reported, however, detailed descriptions of the kidney manifestations of HPS are lacking. More critically, the diagnosis of HPS is rarely supported by renal biopsy specimens. We report four rare cases of biopsy-proven renal-limited HPS in patients presenting with acute kidney injury (AKI). The available evidence on this topic is critically discussed in light of the possible emergence of an autonomous entity characterized by an isolated kidney involvement.

POS0824 SAFETY AND EFFICACY OF THE INTENSIFIED B CELL DEPLETION INDUCTION THERAPY FOR PATIENTS WITH ANCA-ASSOCIATED VASCULITIS AND SEVERE RENAL INJURY: A CONTROLLED STUDY

Background

Rituximab (RTX), an anti-CD20 monoclonal antibody, has shown to be an effective induction treatment for small-vessel vasculitides associated with antineutrophil cytoplasm antibodies (AAV) in both newly diagnosed and relapsing patients. However, the role of RTX in the management of the most severe cases of AAV remains to be fully elucidated.

Objectives

to assess both safety and efficacy of an intensified B-cell depletion therapy (IBCDT) protocol, including RTX, cyclophosphamide (CYC), and methylprednisolone pulses without additional maintenance immunosuppressive therapy compared to conventional therapy regimen based on oral CYC and steroids and prolonged maintenance therapy with azathioprine (AZA) in patients with AAV and severe renal injury.

Methods

A cohort of 15 AAV patients with the most severe features of AVV renal involvement (as <15 ml/min GFR and histological findings of paucimmune necrotizing glomerulonephritis with more than 50% crescents of non-sclerotic glomeruli at the renal biopsy) was treated IBCDT and compared to compared toa control group of 10 patients with AAV treated with a conventional therapy regimen based on oral CYC and steroids and prolonged maintenance therapy with azathioprine (AZA). Independently on the pharmacologic regimen, plasma exchange (7 procedures with 1-1.5 plasma volume replacement) was performed in the presence of 1. alveolar haemorrhage, and 2. more than 50% florid crescents in the nonsclerotic glomeruli, or 3. dialysis dependence.

Results

Complete clinical remission (BVAS 0) was observed at 6 months in 14 of 15 patients (93%). All cases treated with IBCDT who achieved a complete clinical remission experienced a depletion of peripheral blood B cells at the end of therapy. Of the 10 dialysis dependent patients at onset, 6 subjects (60%) experienced a functional recovery allowing the suspension of dialysis treatment. When compared to the control group, no statistically significant difference was observed in patients treated with IBCDT in terms of overall survival, 6-month therapeutic response rate, and 6-, and 12-month functional renal recovery. The cumulative total dose of CYC in the case group was on average 1 g/patient while in the control group on average 8.5 g / patient (p = 0.00008). Plasmapheresis sessions were performed at part of the induction therapy among 13 patients (87%) in the case group and 8 (80%) in the control group.

Conclusion

The results of this study showed that IBCDT appeared to be safe and has the same efficacy profile when compared to conventional therapy with CYC plus AZA in the management of the most severe patients with AAV. Additionally, this avoids the need of prolonged maintenance therapy for long, and limits the exposure to CYC with consequent reduced toxicity and drug-related side effect rates.

Disclosure of Interests

None declared

Treating Patients With ANCA-Associated Vasculitis and Very Severe Renal Injury With an Intensified B Cell Depletion Therapy: Comparison With a Control Cohort Receiving a Conventional Therapy

Rituximab (RTX), an anti-CD20 monoclonal antibody, has shown to be an effective induction treatment for small-vessel vasculitides associated with antineutrophil cytoplasm antibodies (AAV) in both newly diagnosed and relapsing patients. However, the role of RTX in the management of the most severe cases of AAV remains to be fully elucidated. The aim of this study was to assess both safety and efficacy of an intensified B-cell depletion therapy (IBCDT) protocol, including RTX, cyclophosphamide (CYC), and methylprednisolone pulses without additional maintenance immunosuppressive therapy in a cohort of 15 AAV patients with the most severe features of AVV renal involvement (as <15 ml/min GFR and histological findings of paucimmune necrotizing glomerulonephritis with more than 50% crescents of non-sclerotic glomeruli at the renal biopsy). Results of the IBCDT regimen have been compared to those obtained in a control cohort of 10 patients with AAV treated with a conventional therapy regimen based on oral CYC and steroids followed by a prolonged maintenance therapy with azathioprine (AZA). Plasma exchange was equally employed in the study and the control group. Complete clinical remission (BVAS 0) was observed at 6 months in 14 of 15 patients treated with IBCDT (93%). All cases who achieved a complete clinical remission experienced a depletion of peripheral blood B cells at the end of therapy. Of the 10 dialysis dependent patients at onset, 6 subjects (60%) experienced a functional recovery allowing the suspension of dialysis treatment. When compared to the control group, no statistically significant difference was observed in patients treated with IBCDT in terms of overall survival, 6-month therapeutic response rate, and 6-, and 12-month functional renal recovery. The cumulative total dose of CYC in the case group was on average 1 g/patient while in the control group on average 8.5 g/patient (p = 0.00008). Despite the retrospective design and relative limited sample size, IBCDT appeared to be safe and had the same efficacy profile when compared to the conventional therapy with CYC plus AZA in the management of the most severe patients with AAV. Additionally, this avoided the need of prolonged maintenance therapy for long, and limited the exposure to CYC with consequent reduced toxicity and drug-related side effect rates.

Management of acute kidney injury in frail patients with biopsy-proven cast nephropathy: a combined approach with chemotherapy plus Supra-hemodiafiltration with post-adsorption endogenous reinfusion

BACKGROUND

Patients with multiple myeloma often have kidney involvement with acute kidney injury which is frequently due to cast nephropathy. Hemodiafiltration with endogenous reinfusion (HFR) allows removal from the circulation of significant amounts of free light chains (FLCs) responsible for tubular damage.

METHODS

Between 2014 and 2018, 13 patients affected by multiple myeloma (64% λ chain and 36% k), including 10 cases with biopsy-proven cast nephropathy, were treated with this technique. Each patient had high free light chains levels at diagnosis: median 8586 mg/l for λ and 4200 mg/l for k, and stage III acute kidney injury (median serum creatinine 7.5 mg/dl). We initially performed daily HFR-Supra sessions and then modulated them based on renal response (mean 10 sessions/patient). At the same time, the patients also received various chemotherapy regimens, depending on their hematological criteria.

RESULTS

Forty-six percent of patients showed at least partial renal function recovery within the third month, thus allowing dialysis discontinuation; 38% remained on dialysis. Two patients died. The mean reduction rate of free light chains at the end of the HFR-Supra cycle was 85% (k) and 40% (λ), respectively. Serum albumin remained stable during the whole treatment.

DISCUSSION

In our experience, the synergistic effect of chemotherapy and HFR-Supra led to a recovery of renal function in 6 out of 13 patients presenting with severe dialysis-requiring acute kidney injury. HFR-Supra allowed stable albumin levels, with high free light chains removal rate, at a relatively low costs.

POS0704 LONG-TERM CLINICAL OUTCOMES OF PATIENTS WITH LUPUS NEPHRITIS TREATED WITH AN INTENSIFIED B-CELL DEPLETION PROTOCOL: A PROSPECTIVE STUDY

Background:

B cells play a key role In the pathogenesis of Lupus Nephritis (LN).

Objectives:

we aim to investigate the safety and efficacy of an intensified B-cell depletion induction therapy (IBCDT)without immunosuppressive maintenance regimen compared to standard of care in biopsy-proven LN.

Methods:

Thirty patients were administered an IBCDT (4 weekly Rituximab 375mg/m2 and 2more doses after 1&2 months;2 infusions of 10 mg/kg cyclophosphamide (CYC),3 methylprednisolone pulses), followed by oral prednisone (tapered to 5 mg/day by the 3rd month). No immunosuppressive maintenance therapy was given. Thirty patients matched for LN class and age were selected as controls: 20 received 3 methylprednisolone pulses days followed by oral prednisone and mycophenolate mofetil (MMF) 2-3 g/day, while 10 were given the Euro Lupus CYC.

Results:

At 12 months, complete renal remission was observed in 93% of patients on IBCDT, in 62.7% on MMF, and in 75% on CYC (p=0,03); the dose of oral prednisone was lower in the IBCDT group (mean±SD 2.9±5.0mg/dl) than MMF (10.5±8.0 mg/day,p<0.01) or CYC group (7.5±9.0mg/day,p<0.01). Mean follow-up after treatment was 44.5 months (IQR 36–120months), 48.6 months (IQR36–120months), and 45.3 (IQR36–120months) for IBCDT, MMF and CYC, respectively. At their last follow-up visit, we observed no significant differences in proteinuria and serum creatinine, nor in the frequency of new flares among the three groups.

Conclusion:

In biopsy proven LN, the IBCDT without further immunosuppressive maintenance therapy was shown to be as effective as conventional regimen of MMF or CYC followed by a 3-year maintenance MMF regimen. Moreover, the use of IBCDT was associated with a marked reduction of glucocorticoid cumulative dose.

Disclosure of Interests:

None declared

Monoclonal Gammopathy of Renal Significance: Clinical and Histological Efficacy of a Bortezomib-Based Regimen

Monoclonal Gammopathy of Renal Significance (MGRS) is a group of heterogeneous disorders characterized by renal dysfunction secondary to the production of a monoclonal immunoglobulin by a nonmalignant B cell or plasma cell clone. We report the clinical and histological outcomes of two patients with biopsy-proven MGRS: one patient showed membranoproliferative glomerulonephritis with monoclonal k-light chain and C3 deposits, the second patient showed immunotactoid glomerulopathy. Both patients were treated with a 9-month chemotherapy protocol including bortezomib, cyclophosphamide, and dexamethasone. Renal biospy was repeated after 1 year. The estimated glomerular filtration rate (eGFR) increased from 22.5 (baseline) to 40 ml/min per 1.73 m2 after 12 months, then to 51.5 ml/min per 1.73 m2 after 24 months; proteinuria decreased from 4.85 (baseline) to 0.17 g/day after 12 months, then to 0.14 g/day after 24 months. Repeat renal biopsies showed a dramatic improvement of the glomerular proliferative lesions and near complete disappearance of the immune deposits. A bortezomib-based treatment proved very effective and was well-tolerated in the two patients presenting with clinically and histologically aggressive MGRS.

The Challenging Management of Cancer: An Immunonephrologist's Perspective

INTRODUCTION

Onconephrology is an emerging medical subspecialization that focuses on the numberless interrelations between cancer and kidney diseases. Tumor cells evade immune surveillance through activation of immune checkpoint pathways that suppress antitumor immune responses. By blocking checkpoints, new anticancer agents disrupt immune homeostasis but potentially induce immune-mediated diseases. Nephrologists and nephroimmunologists should be able to treat the nephrotoxic sequelae of cancer therapy and ensure continuation of the life-saving treatment.

METHODS

Thirty-seven renal biopsies have been carried out over 42 months in oncologic patients, that is, 5.2% of the total native renal biopsies were carried out in the same period. The commonest diagnoses (>6 cases) were interstitial tubular nephritis, membranous glomerulopathy, IgA nephropathy, vasculitis, and focal and segmental glomerulosclerosis.

CASE PRESENTATION

Three example cases, including focusing on key questions which could involve the nephrologists are reported in detail. They include a cancer-related Goodpasture Syndrome, the peculiar toxic effects of pemetrexed on tubular cells, and the intriguing relationship between bevacizumab and cryoglobulinemic glomerulonephritis.

CONCLUSION

As shown by these 3 example cases, nephrologists need to be open-minded with regard to kidney biopsy in order to get a timely diagnosis. Nephrologists also need to improve their knowledge of cancer biology and therapy in order to prevent kidney problems, manage therapy-related immune-mediated disorders, and improve patient life expectancy.

Long-term effects of intensive B cell depletion therapy in severe cases of IgG4-related disease with renal involvement

IgG4-related disease (IgG4-RD) is an immune-mediated disorder often showing elevated serum IgG4 concentrations, dense T and B lymphocyte infiltration, and IgG4-positive plasma cells and storiform fibrosis. We prospectively evaluated for 4 years 5 patients with histologically proven IgG4-RD of whom 3 had tubulointerstitial nephritis (TIN) and 2 had retroperitoneal fibrosis (RPF). They received an intensive B depletion therapy with rituximab. The estimated glomerular filtration rate of TIN patients after 1 year increased from 9 to 24 ml/min per 1.73 m2. IgG/IgG4 dropped from 3236/665 to 706/51 mg/dl, C3/C4 went up from 49/6 to 99/27 mg/dl, and the IgG4-RD responder index fell from 10 to 1. CD20+ B cells decreased from 8.7 to 0.5%. A striking drop in interstitial plasma cell infiltrate as well as normalization of IgG4/IgG-positive plasma cells was observed at repeat biopsy. Both clinical and immunological improvement persisted over a 4-year follow-up. Treating these patients who were affected by aggressive IgG4-RD with renal involvement in an effort to induce a prolonged B cells depletion with IgG4 and cytokine production decrease resulted in a considerable rise in eGFR, with IgG4-RD RI normalization and a noteworthy improvement in clinical and histological features. Furthermore, the TIN subgroup was shown not to need for any maintenance therapy.

P0245PERCUTANEOUS RENAL BIOPSY IN FRAIL AND HIGH RISK PATIENTS

Background and Aims:

Many patients with End Stage Kidney Disease do not undergo percutaneous kidney biopsy (KB) and do lack a definite diagnosis. Whether KB is beneficial in the extreme patients’ categories, i.e., age &gt;75 years and very late referrals with kidney disease requiring renal replacement therapy at the first evaluation, remains controversial. Aim: To analyse the benefit/risk balance in terms of therapeutic options and general outcome of KB procedure in these borderline categories.

Method

Files for all biopsies performed in our Centre between 2013 and 2019 (# 903 inpatients’ native kidney) were retrospectively analysed with special focus on histological diagnosis, biopsy complications, and post-biopsy patient’s outcome. Two groups of high risk patients were identified 1. &gt;75 years old patients, and 2. patients requiring dialysis at the first clinical evaluation. A rigorous protocol of screening of the bleeding risks was adopted.

Results

Of the 903 biopsies, 217 cases (24%) had group 1, and 92 (10%) group 2 criteria. Group 1: mean age 80 years (range 75-92), main histological diagnoses: ANCA associated vasculitis (AAV) (12,4%); membranous nephropathy (MN) (11,5%), diabetic nephropathy (10,1%), IgA glomerulonephritis (IgAGN) (9,2%), cast nephropathy (9,2%), renal amyloidosis (9.2%), focal segmental glomerulosclerosis (FSGS - 7,8 %). Group 2: mean age 60 years (range 20-92), most frequent histological diagnosis: AAV (26,1%); cast nephropathy (19,6 %), nephroangiosclerosis (9,8%), IgAGN (7,6 %), diabetic nephropathy (6,5%), renal amyloidosis (5,4%); FSGS (4,3%). Five major complications (2,3%), including AV fistula with spontaneous resolution in 4 patients and 1 case of severe bleeding requiring arterial embolization, and 14 minor complications (6,5%), including post biopsy haematomas &lt;2cm in 12 patients and haematuria in 2 patients were observed in group 1. Only 1 (1%) major complication (AV fistula) and 4 minor complications (4,3%), including post biopsy &lt;2cm haematomas in group 2 were identified in group 2. Histological diagnosis conditioned or changed treatment strategy in 71% of elderly patients (group 1), and 63% of patients in dialysis (group 2). Dialysis discontinuation was achieved in 30 out of 92 patients (36,6%) with a sparing of over 1 million euro/year.

Conclusion

Given its high diagnostic value (especially in patients who are willing to be transplanted), the prognostic significance (and the assessment of the extent of the renal sclerotic changes), and the potential impact on the treatment policy, indications to percutaneous kidney biopsy in elderly and dialysis patients should be probably revised.

P0206RITUXIMAB IN ADULT ONSET OF IGA VASCULITIS WITH SEVERE RENAL INVOLVEMENT: A SINGLE CENTER EXPERIENCE

Background and Aims

IgA-vasculitis (IgAV) is a systemic small vessels vasculitis characterized by deposition of underglycosylated IgA1 immune complexes. Renal involvement indicates severity of illness and chronic kidney disease represents the most serious long-term complication of IgAV. Presently, no treatment is specifically recommended in IgAV Glucocorticoids (GC) have been traditionally thought to be effective in tempering systemic symptoms, but did not show long-term benefits either in reducing flares or progression of kidney disease. The effectiveness of conventional immunosuppressants is controversial. Recently Rituximab (RTX) has been proved to be effective in a few case series of adults with IgAV. However, long term results are lacking. Aim of the study: to evaluate the effectiveness of RTX as first line therapy in induction and maintenance of remission of adults with IgAV with biopsy-proven crescentic glomerulonephritis.

Method

We reviewed the clinical records of patients with adult-onset IgAV treated with RTX at our Center. Patients included 8 males and 4 females, mean age 45 years (range 19-75) with mean follow-up duration of 31 months (range 6-144). Diagnosis was based on the combination of clinical assessment, serological tests and histological analysis according to EULAR criteria. All patients (pts) had a biopsy proven IgAV- severe nephritis. RTX was given for the treatment of relapsing or refractory disease or because of definite contraindications to standard dose CS and/or conventional immunosuppressants. Patients received 4 weekly doses of RTX (375 mg/m2) given alone (8 pts) or in combination with CS (4 pts). Disease activity was evaluated by Birmingham Vasculitis Activity Score version 3 at the onset and at 1, 6 and 12 months and at the end of follow up. Complete remission (CR) was defined as BVAS of 0

Results

Eleven pts (91.7%) achieved a clinical response at 6 months. Ten pts had a CR while 1 pt had a partial response and was given an additional dose of RTX after 12 months from induction due to persistent proteinuria (1gr/24 hrs), despite systemic remission. He achieved a CR 6 months later. One patient did not respond to RTX and was switched to MMF. Among the 10 pts with CR, 1 patient needed maintenance doses of RTX every 6 months due to relapse of palpable purpura; 1 relapsed after 15 months and received a new induction course showing a CR again.

Significant decrease in 24-hour proteinuria (P = 0.043), BVAS (P = 0.031),and CRP level from RTX initiation through the last follow-up visit was detected. RTX was generally well tolerated. One patient, who had a CR with RTX alone died after 6 months of follow-up for cardiovascular cause.

Conclusion

This extended experience confirms our initial results supporting the use of RTX in the treatment of IgAV with severe renal involvement. Indeed, RTX proved to be effective and safe for induction and maintenance of long-lasting remission. Present data also suggest that RTX is not only effective for severe and refractory IgAV, but can be also proposed as a first line therapy.

Outcome of patients with severe AL amyloidosis and biopsy-proven renal involvement ineligible for bone marrow transplantation

INTRODUCTION

AL amyloidosis is caused by a clone of plasma cell. Due to the impact of the disease on patient survival, careful evaluation of organ involvement is essential and treatment should be tailored to single patient's risk.

AIM

We analyzed the clinical, laboratory and histological characteristics of 21 elderly patients (pts) (mean age 74.7 ± 7.97 years, range 55-81) with AL amyloidosis, including 17 patients (81%) with biopsy-proven renal involvement, who were ineligible for bone marrow transplantation, and evaluated the impact of renal impairment on survival.

RESULTS

Cardiac and renal involvement was found in 14 (67%) cases. Among the 17 patients with renal involvement, 12 had renal failure with proteinuria, and one showed isolated renal failure and vascular amyloid deposition. Hematological response occurred in 57.1% after first line therapy (75% after three cycles). In six of the patients with renal involvement, proteinuria decreased from 4.2 to 1.1 g/24 h (range 0.2-3 g/24 h), serum Creatinina (sCr) levels declined or stabilized. Severe renal failure at diagnosis was found to directly influence patient survival, while the Staging System for Renal Outcome in AL Amyloidosis did not associate with outcomes.

CONCLUSIONS

To the best of our knowledge this is the first case series in which the whole cohort of patients with urinary or functional abnormalities underwent a histological evaluation. None of the patients were eligible for bone marrow transplantation. Hematologic response was 57.1%, while renal response was much lower (35%). Of note, the Staging System did not completely apply to this peculiar setting of patients in whom renal involvement was not presumptive but biopsy-proven. More aggressive approaches may be needed in these patients to avoid the inexorable progression of the disease.

Rituximab in severe immunoglobulin-A vasculitis (Henoch-Schönlein) with aggressive nephritis

OBJECTIVES

Immunoglobulin-A vasculitis (IgAV) is a systemic small-vessel vasculitis in which renal involvement indicates severity of illness, and chronic kidney disease represents the most serious long-term complication. No treatment at present is specifically recommended for IgAV. Recently, rituximab (RTX) has been shown to be effective in case series of adults with IgAV. However, long term results are lacking. Aim of the study is to evaluate the effectiveness of RTX as induction therapy and maintenance of remission in adults with severe IgAV and aggressive glomerulonephritis.

METHODS

This study included 12 adult-onset patients, 8 males and 4 females, mean age 45.1 years (range 19-75) with a mean follow-up duration of 33.7 months (range 6-144). All patients had a severe IgAV with biopsy proven crescentic nephritis. RTX was given for the treatment of a refractory disease or because of definite contraindications to standard therapies.

RESULTS

Eleven patients (91.7%) achieved a clinical response at 6 months. Ten patients had a complete response (CR) while one had a partial response and was given an additional dose of RTX after 12 months for persistent proteinuria (1gr/24 hrs) despite systemic remission. He achieved a CR 6 months later. One patient was considered unresponsive to RTX and was switched to MMF. Among the 10 patients with CR, 1 needed maintenance doses of RTX every 6 months for iterative relapsing of severe purpura, 1 relapsed after 15 months and received a new induction course showing a CR again. A significant decrease in BVAS (p=0.031) and 24-hour-proteinuria (p=0.043) from RTX initiation through the last follow-up has been detected. One patient, who had a CR with RTX alone died after 6 months for therapy-unrelated cardiovascular cause.

CONCLUSIONS

RTX proved to be effective and safe for induction and maintenance of long-lasting remission in severe IgAV with aggresive renal involvement. Data also suggest that RTX can be indicated not only for refractory cases, but can be also proposed as a first line therapy.

[Monoclonal gammopathy of renal significance and membranoproliferative glomerulonephritis: a complex relationship with promising therapeutic opportunities]

In the last few years, the increasing awareness of the complex interaction between monoclonal component and renal damage has determined not only a new classification of the associated disorders, called Monoclonal Gammopathy of Renal Significance (MGRS), but has also contributed to emphasize the importance of an early diagnosis of the renal involvement, which is often hard to detect but can evolve towards terminal uraemia; it has also pointed at the need to treat these disorders with aggressive regimens, even if they are not strictly neoplastic. The case described here presented urinary abnormalities and renal failure secondary to a membranoproliferative glomerulonephritis (MPGN), with intensively positive immunofluorescence (IF) for monoclonal k light chain and C3, and in the absence of a neoplastic lympho-proliferative disorder documented on bone marrow biopsy. After the final diagnosis of MGRS, the patient was treated with several cycles of a therapy including dexamethasone, cyclophosphamide and bortezomib, showing a good functional and clinical response.

Rituximab as a front-line therapy for adult-onset minimal change disease with nephrotic syndrome

Minimal change disease (MCD) accounts for 15% of adult nephrotic syndrome (NS) cases. Adult-MCD patients may have more severe clinical features than pediatric patients. In children, Rituximab (RTX) has been used since 2006 to treat frequently relapsing NS. In adults, data about the efficacy of RTX for MCD are limited. We report our experience on the use of RTX in adult biopsy-proven MCD. Our series includes 6 adult patients (2 males and 4 females), age 45–73 years, treated with RTX (4 weekly doses of 375 mg/m²). Proteinuria decreased from 11,2 (23–4.8) g/24 hours to 0.6 (0–2) g/24 hours after 6 months, and to 0.4 (0–1, 4) g/24 h in the 4 pts with the longer follow-up. Creatinine decreased from 1.95 (0.5–5) mg/dl to 0.88 (0.6–1.3) mg/l. Five patients achieved a complete renal remission, while in 1 pt proteinuria decreased by 75%. RTX successfully depleted CD19 lymphocytes in 100% of pts for at least 6 months. No clinically relevant adverse events have been observed. This case series shows a remarkable efficacy of RTX in treatment of MCD. RTX can be an attractive alternative both in recurrent forms and in induction-therapy of MCD. RTX may be preferentially used in patients at a high risk of development of the adverse effects of corticosteroids and should be considered as an alternative option in patients with recurrent NS. Additional data are needed to inform clinical practice on how best to use RTX in this patient population, so that definitive randomized trials can be planned.

IgG4-related kidney disease: the effects of a Rituximab-based immunosuppressive therapy

IgG4-related disease (IgG4-RD) is a recently recognized disorder, characterized by elevated serum IgG4 concentrations, dense tissue infiltration of IgG4-positive plasma cells and storiform fibrosis. Treatment is usually based on steroids, however, relapses and long-term adverse effects are frequent. We prospectively studied 5 consecutive patients with histologically-proven IgG4-RD and renal involvement, treated with an extended Rituximab protocol combined with steroids. Two doses of intravenous cyclophosphamide were added in 4 patients. Five patients with IgG-RD were investigated: three had tubulointerstitial nephritis (TIN), while two had retroperitoneal fibrosis (RPF). In the patients with TIN, renal biospy was repeated after 1 year. In the patients with TIN, estimated glomerular filtration rate (eGFR) at 12 months increased from 9 to 24 ml/min per 1.73 m²; IgG/IgG4 decreased from 3,236/665 to 706/51 mg/dl; C3/C4 increased from 49/6 to 99/27 mg/dl; CD20⁺ B-cells decreased from 8.7% to 0.5%; Regulatory T-cells decreased from 7.2% to 2.5%. These functional and immunologic changes persisted at 24 months and in two patients at 36 months. A repeat renal biopsy in the patients with TIN showed a dramatic decrease in interstitial plasma cell infiltrate with normalization of IgG4/IgG positive plasma cells. The patients with RPF showed a huge regression of retroperitoneal tissue. In this sample of patients with aggressive IgG4-RD and renal involvement, treatment aimed at depleting B cells and decreasing antibody and cytokine production was associated with a substantial, persistent increase in eGFR, and a definite improvement in immunologic, radiologic and histological parameters.

Lymphocyte Subsets Assayed by Numerical Tests in CAPD

Peripheral and peritoneal lumphocytes were assayed by numerical tests in adults on peritoneal dialysis. T lymphocytes were classified by monoclonal antibodies (OKT3, OKT4, OKT8) and B lymphocytes by the presence of surface immunoglobulins, using the immunofluorescence technique.

Peripheral T cells showed no significant change from the normal, except for T suppressor cells which increased in patients with 2 or more peritonitis episodes.

Examination of peritoneal lymphocytes showed a significant reduction in S-IgA lymphocytes (B cells bearing IgA receptors) and an increase in T-suppressor cells (OKT8+) in patients who developed peritonitis in the follow-up study. The implications of these results are discussed with particular reference to susceptibility to peritonitis.

Carotid Intima-Media Thickness and Anti-Phospholipid Antibodies in Patients with Systemic Lupus Erythematosus

An increase in mortality due to accelerated atherosclerosis has been reported in patients affected with Systemic Lupus Erythematosus (SLE). Anti-phospholipid antibodies (aPA) may play a pathogenetic role in the development of atherosclerosis. We measured carotid intima-media thickness (IMT), as a surrogate parameter of atherosclerosis, by B-mode ultrasound examination in 42 patients affected with SLE (11 men and 31 women) and in 42 healthy age- and sex-matched subjects. Lupus Anticoagulant (LA) (APTT sensitive, silica clotting time, DRVVT), Anti-cardiolipin antibodies (ACA) IgG and IgM, anti-β2glycoprotein 1 (anti-β2GP1) IgG and IgM and anti-prothrombin (anti-PT) IgG and IgM in ELISA (Orgentec Bouty) were also detected. IMT was 0.538±0.128 mm (0.310–0.866 mm) in SLE vs 0.473±0.084 mm in healthy subjects (-p 0.003–). IMT correlated with patients’ age (p<0.005) and with C Reactive Protein (CRP) (p<0.005), but not with years of disease, hypertension, number of anti-hypertensive drugs, total cholesterol, serum creatinine and proteinuria. Sixteen patients (38%) had aPL: 12 LA, 6 ACA IgG, 4 ACA IgM, 4 anti-β2GP1 IgG, 3 anti-β2GP1 IgM, 2 anti-PT IgG and 1 anti-PT IgM. IMT was not statistically correlated with aPA. Positive and negative aPA patients only differed as regards glomerular filtration rate (76 ml/min vs 113 ml/min - p<0.01–). Frequency of aPA positivity was 50% in Patients with IMT >0.600 mm and 33.3% in those with IMT <0.600 mm. If LA positivity was considered separately, it was 41.6% in patients with IMT >0.600 mm and 23.3% in patients with IMT <0.600 mm. Among the 5 patients with IMT >0.7 mm, 2 had LA positivity (40%) vs 10/37 (27%) of those with minor carotid thickness. In conclusion, IMT, a surrogate parameter of atherosclerosis, was correlated with Patients’ age and CRP and not with presence of aPA, even though, in the group of patients with greater IMT, there was a non-significant higher proportion of positivity for anti-phospholipid antibodies, in particular for Lupus Anticoagulant.

IgG4-related nephropathy

IgG4-related disease (IgG4-RD) is a recently recognized disorder, often with multiple organ involvement, characterized by dense tissue infiltration of IgG4-positive plasma cells, storiform fibrosis, obliterative phlebitis and frequently elevated serum IgG4 concentration. The kidney can be involved either directly or indirectly. The most frequent direct renal manifestations of IgG4-RD are IgG4-related tubulointerstitial nephritis (TIN) and membranous glomerulonephropathy. Retroperitoneal fibrosis (RPF) is another condition that is frequently IgG4-related and that can indirectly affect the kidney causing ureteral obstruction and hydronephrosis. Contrast-enhanced computerized tomography, magnetic resonance imaging and (18)F-fluorodeoxyglucose positron emission tomography/computed tomography show different imaging findings and are useful tools for monitoring therapeutic response. Steroid treatment is the first line of therapy, but relapsing or refractory forms of the disease are frequently observed and require more aggressive therapeutic approaches. At our centre, we treated three cases of aggressive IgG4-related TIN and two cases of IgG4-related RPF with an intensified, immune suppressive protocol, obtaining good results without severe adverse effects.

Acute renal infarction: a single center experience

BACKGROUND

Acute renal infarction is a rare condition whose diagnosis is often delayed. Major risk factors include atrial fibrillation, valvular or ischemic heart disease, renal artery thrombosis/dissection and coagulopathy.

METHODS

We reviewed the medical records of 18 patients admitted to our Nephrology Department between 1999 and 2015 for acute renal infarction diagnosed by computed tomography. Tc-99m dimercaptosuccinic acid (DMSA) scintigraphy was performed in some patients during follow-up to assess parenchymal lesions and estimate differential kidney function.

RESULTS

Mean age was 59.8 years. Major associated risk factors included hypertension (44 %), obesity (33 %), atrial fibrillation (28 %), peripheral vascular disease (17 %), smoking (17 %), prior thromboembolic event (11 %), diabetes (11 %), estroprogestinic therapy (11 %). Seventy-two percent of patients presented with flank pain. Mean serum creatinine was 1.2 ± 0.6 mg/dl. Acute kidney injury occurred as the initial manifestation in two patients. Patients were managed conservatively, with low molecular weight heparin (83 %) or aspirin (11 %). At the end of follow-up serum creatinine was 1.1 ± 0.3 mg/dl; one patient remained on chronic hemodialysis. 58 % of patients who underwent renal scintigraphy after a median of 8 months had a reduced contribution of the previously affected kidney to total renal function.

CONCLUSION

Risk factors associated with the development of chronic kidney disease following renal infarction are unknown. In our subjects, renal function remained stable in all but one patient who developed end stage renal disease. Further studies should focus on etiology and evolution of kidney function in patients with acute renal infarction.

[Pyelonephritis]

Acute pyelonephritis (APN) is a frequent pathological condition. Its etiology is prevalently due to E. coli and risk factors include sexual activity, genetic predisposition, old age and urinary instrumentation. No correlation between APN and vesicoureteral reflux has been established in adults. The diagnosis of APN is usually clinical, but computed tomography (CT) and magnetic resonance imaging (MRI) allow a more precise definition and can document evidence of abscesses. Severe cases should be treated with a fluoroquinolone or an extended-spectrum cephalosporin. Treatment should last 10-14 days. The long-term evolution of APN is prevalently favorable in adults, even though formation of cortical scars and development of macroalbuminuria and renal failure have been described. The formation of renal abscesses is underestimated and must be evaluated by CT or MRI. Abscesses need to be drained only when they are large, and medical treatment is successful in the majority of cases.

Acute pyelonephritis in adults: a case series of 223 patients

BACKGROUND

Acute pyelonephritis (APN) is a common disease which rarely evolves into abscesses.

METHODS

We prospectively collected clinical, biochemical and radiological data of patients hospitalized with a diagnosis of APN from 2000 to 2008.

RESULTS

Urinary culture was positive in 64/208 patients (30.7%) and blood cultures in 39/182 cases (21.4%). Two hundred and thirteen patients were submitted to computed tomography (CT) or nuclear magnetic resonance (NMR): confirmation of APN was obtained in 196 patients (92%). Among these, 46 (23.5%) had positive urine culture, 31 (15.8%) had positive blood culture and 15 (7.6%) had positive cultures of both urine and blood. In 98 patients, either urine or blood cultures were negative, but CT/NMR were positive for APN. Fifty of the 213 patients submitted to CT/NMR (23.5%) had intrarenal abscesses: only 2 were evidenced by ultrasound examination. No differences were found between patients with positive or negative CT with regards to fever, leucocytosis, C-reactive protein, pyuria, urine cultures and duration of symptoms before hospitalization. No differences were found between patients with or without abscesses with regards to these parameters and risk factors. Patients with abscesses had a longer duration of treatment and hospitalization.

CONCLUSIONS

Our data suggest that in APN it is not always possible to routinely document urinary infection in a clinical setting. This finding could be explained by previous antibiotic treatment, low bacterial growth or atypical pathogens. Systematic CT or NMR is necessary to exclude evolution into abscesses, which cannot be suspected on clinical grounds or by ultrasound examination and may also develop in the absence of risk factors.

[Vesicoureteral reflux in adults]

Vesicoureteral reflux (VUR) may be congenital or acquired. The most frequent form of congenital VUR is primary VUR. Its prevalence in adults is not exactly known, but it is higher in women, whose greater propensity for urinary tract infections increases the likelihood of an instrumental examination leading to the diagnosis of less severe cases. In men, even severe VUR may go undiagnosed for a long time. Primary VUR is due to a defect in the valve mechanism of the ureterovesical junction. In physiological conditions, the terminal ureter enters the bladder wall obliquely and bladder contraction leads to compression of this intravesical portion. Abnormal length of the intravesical portion of the ureter due to a genetic mutation (whose location is yet to be established) leads to VUR. In its less severe forms VUR may be asymptomatic, but in 50-70% of cases it manifests with recurrent cystitis or pyelonephritis. The manifestations leading to a diagnosis of VUR in adults, besides urinary tract infections, are proteinuria, renal failure and hypertension. The gold-standard diagnostic examination is a micturating cystourethrogram. Reflux nephropathy develops as a result of a pathogenetic mechanism unrelated to high cavity pressure or urinary tract infections but due to reduced formation of the normal renal parenchyma (hypoplasia or dysplasia). Abnormal renal parenchyma development is attributable to the same genes that control the development of the ureters and ureterovesical junction. VUR is considered only a marker of this abnormal development, playing no role in scar formation. There is no conclusive evidence regarding the indications for VUR correction. However, the risk that VUR leads to recurrent pyelonephritis and reflux nephropathy must be kept in mind. VUR certainly has to be corrected in women who contemplate pregnancy.

[Activity in a nephrology ward in 2009, Piemonte, Italy]

The characteristics of patients hospitalized in nephrology wards in Italy have changed in recent years due to the aging Italian population and the increased immigration. We analyzed the demographic and clinical characteristics of patients hospitalized in our nephrology ward (17 beds) from 15 November 2008 to 15 November 2009. In this period there were 507 hospitalizations including 448 patients. The mean age was 64.4+/-18 years (range 16-96 years). Foreigners accounted for 10% of the total; their mean age was significantly lower than that of Italian patients (38.2+/-13.4 vs 67.4+/-15.9 years, p<0.01). 36.3% of patients were on dialysis, 10% were transplant recipients: the reasons for admission in these cases were internal medicine related; 18.15% were hospitalized because of emergency unit crowding without indications for admission to a nephrology ward. Hospitalization lasted a mean of 13+/-13 days. The most frequent diagnosis at discharge was acute renal failure (ARF) (28.9%) (prerenal 42.1%, obstructive 12.2%, drug induced 6.8%, other causes of ARF 38.7%). Patients with ARF were older than patients with other kidney conditions (67.05+/-16.98 vs 56.03+/-18.65 years, p<0.01). ARF resolved or improved in 86 patients (63.7%). Other diagnoses were cardiovascular disease 25.1%, glomerular disease 18.7%, acute pyelonephritis 10.6%, other 16.7%. Foreign patients presented infectionrelated diseases more often than Italian patients (39.2% vs 20.4%, p=0.02). 392 patients were discharged to their homes, 40 (7.9%) found a place in a long-term care facility or home for the elderly, 25 (4.9%) in other hospital units, and 50 patients died (9.8%). In conclusion, patients hospitalized in nephrology wards in 2009 were mostly elderly with a high frequency of cardiovascular disease and diabetes. The most frequent diagnosis was prerenal ARF. These data suggest the necessity of improving the prevention of this type of kidney disease. Moreover, the length of hospitalization, which is increasing because of difficult clinical and social situations, could be shortened if more nursing homes, convalescent homes and homes for the elderly were available in Italy.

[Cancer treatment-induced nephrotoxicity: BCR-Abl and VEGF inhibitors]

The nephrotoxicity of some cancer drugs is well known. Given the rapid development of cancer research, careful assessment of patients treated with new drugs, which may have new toxicity profiles, is mandatory. The nephrotoxicity of cisplatin is likely due to inhibition of autophagy priming, while that of methotrexate is related to direct tubular toxicity and intratubular precipitation. Both can be prevented by adequate hydration. The mechanism of radiation nephropathy development is unclear, but chronic oxidative stress and inflammation seem to play a key role. Mesangiolysis is a characteristic feature, followed by vascular alterations, atrophy, fibrosis, and necrosis. Inhibitors of vascular endothelial growth factor (VEGF), such as bevacizumab, sunitinib, and sorafenib, interfere with angiogenesis. Bevacizumab is a humanized monoclonal antibody which binds to circulating VEGF. Sunitinib and sorafenib are small molecules inhibiting tyrosine kinase of the intracellular domain of the VEGF receptor. Treatment with anti-VEGF drugs is frequently complicated by proteinuria, acute renal failure, and hypertension. The most frequent histological lesion is thrombotic microangiopathy. Inhibitors of the BCR-Abl tyrosine kinase domain on the Philadelphia chromosome (imatinib, nilotinib and dasatinib) may cause acute renal failure.

[Isolated microhematuria: biopsy, yes or no?]

Isolated asymptomatic hematuria is frequently encountered in clinical practice but there are no established recommendations for its evaluation and management. There is controversy regarding which tests are necessary and whether renal biopsy is indicated. In the pediatric population, renal biopsy should be considered if there is evidence of progressive renal disease or when parents are worried about their child's diagnosis or prognosis. In adults, examinations for isolated microhematuria should include exclusion of pharmacological causes, journeys to endemic areas for S. haematobium or tuberculosis, sickle-cell disease, endometriosis and, in patients older than 40 years, kidney, ureteral or bladder cancer. Examination of urinary sediment may help in identifying the origin of microhematuria. If it is decided to perform a renal biopsy, the patient should be carefully informed of the possible complications of renal biopsy, including the possibility of finding normal renal tissue.

Retroperitoneal fibrosis and schistosomiasis: a causal relationship?

Retroperitoneal fibrosis (RPF) is characterized by replacement of the normal tissue of the retroperitoneum with fibrosis and/or chronic inflammation. About two-thirds of cases of RPF are idiopathic and one-third is secondary to drugs, infections (tuberculosis, syphilis, actinomycosis, fungal infections), retroperitoneal hemorrhage, or malignancy. We report the case of a patient who was diagnosed as having RPF and schistosomiasis caused by Schistosoma haematobium with histological documentation. He was treated with praziquantel and afterwards with corticosteroids with remission of RPF. To our knowledge, the association between schistosomiasis and RPF has not been described in the literature. We postulate that there is a causal relationship between these two conditions.

[Thrombotic microangiopathy during urinary tract infection]

An 84 year-old woman was admitted because of sepsis, thrombocytopenia, anaemia and acute renal failure that required hemodialysis. The diagnostic tests performed during hospitalization showed a severe urinary tract infection due to Enterococcus faecalis, resulting in mild sepsis. This infection was responsible for acute tubular necrosis and thrombotic microangiopathy, in a clinical context of difficult differential diagnosis and hemolytic-uremic syndrome.

Antiphospholipid antibodies and hypertension

Hypertension is a common manifestation of antiphospholipid syndrome (APS). Antiphospholipid antibodies (aPL) have been described in patients with hypertension secondary to renal artery stenosis (RAS). Twenty-six patients with RAS and 25 patients with severe essential hypertension (diastolic blood pressure > 110 mmHg or > or = 3 hypertensive drugs) were studied and compared to 61 age- and sex-matched healthy subjects. Serum samples were tested for lupus anticoagulant (LA), anticardiolipin (aCL) IgG and IgM, antiprothrombin (aPT) IgG and IgM, anti-beta2glycoprotein 1 (abeta2GP1) IgG and IgM. aPL were negative in all patients with RAS. Two patients with essential hypertension had positive aPL (8%) (LA in one patient confirmed in a second assay and abeta2GP1-IgG in the other patient confirmed one year later together with aCL IgG positivity). Among healthy subjects, one case (1.6%) was found to be positive for LA, aCL IgM, abeta2GP1 IgM, aPT IgG, aPT IgM. In conclusion, the association between RAS and aPL seems to be casual rather than an expression of an elective thrombotic localization ofAPS. The positive finding of aPL in 8% of patients with essential hypertension, a frequency higher than that of the control population, deserves further studies in larger series to better explore the relationship between aPL and hypertension.

Light chain deposition disease with renal involvement: clinical characteristics and prognostic factors

BACKGROUND

Light chain deposition disease (LCDD) is characterized by the tissue deposition of monotypical immunoglobulin light chains (LCs). The aim of this study was to investigate its clinical characteristics and prognostic factors.

METHODS

Multicenter study of LCDD with renal and patient survival analyses.

RESULTS

Sixty-three cases were studied (age: 58 +/- 14.2; males: 63.5%; kappa/lambda deposition: 68/32%; underlying disorders: multiple myeloma [MM] 65%, lymphoproliferative disorders 3%, idiopathic 32%). Ninety-six percent presented with renal insufficiency (acute, 52%; chronic, 44%), and 84% with proteinuria >1 g/d. During the follow-up, 36 patients reached uremia (incidence rate: 23.7/100 patient-years) and 37 died (17.5/100 patient-years). The factors independently associated with a worse renal prognosis were age (relative risk [RR], 1.05; 95% confidence interval [CI], 1.009 to 1.086) and serum creatinine at presentation (RR, 1.24; 95% CI, 1.02 to 1.5). Those independently associated with a worse patient survival were age (RR, 1.06; 95% CI, 1.03 to 1.1), MM (RR, 2.75; 95% CI, 1.22 to 6.2), and extrarenal LC deposition (RR, 2.24; 95% CI, 1.15 to 4.35). While kappa-LC deposition was more frequently associated with nodular sclerosing glomerulopathy, histological parameters were not predictors of renal/patient prognosis. The survival of the uremic patients undergoing dialysis was similar to that of patients not reaching uremia.

CONCLUSION

LCDD is characterized by renal insufficiency with proteinuria and has a severe prognosis. Apart from age, the prognostic factors identified were degree of renal insufficiency at presentation affecting the renal prognosis, underlying hematologic disorder and extrarenal LC deposition affecting the patient prognosis. Dialysis is worth performing in uremic LCDD patients.

Is it possible to diagnose primary anti-phospholipid syndrome (PAPS) on the basis of renal thrombotic microangiopathy (PAPS nephropathy) in the absence of other thrombotic process?

The kidneys are a major target of PAPS. The histologic lesions of PAPS nephropathy are vascular; among them thrombotic microangiopathy (TMA) is the most characteristic. It is still not clear in the literature whether the nephropathy can be the unique manifestation of PAPS in the absence of other thrombotic processes; that is: do the renal microthrombotic lesions allow to make the diagnosis of PAPS in presence of anti-phospholipid antibodies (APA)? With this purpose we present three clinical cases. The first patient had severe hypertension C4 hypocomplementemia, thrombocytopenia, and mitralic valve insufficiency. LAC and anti-cardiolipin antibodies at high titre were positive. The histologic picture was characterized by basement membrane reduplication and arteriolar mucoid degeneration, which are features of early phase of TMA. The second patient had severe hypertension. The detection of anti-cardiolipin antibodies was performed several times and resulted positive three times, four months after the diagnosis as well. The renal histologic features were consistent with late lesions of TMA. The third patient had severe hypertension, rapidly progressive renal failure, tricuspidal valve insufficiency and two positive anti-phospholipid antibodies determinations three weeks apart (in two occasions anti-cardiolipin and in one occasion LAC as well were found). The renal lesions were characteristic for TMA. In conclusion we think that patients with TMA and antiphospholipid antibodies can be considered affected by PAPS, as the thrombotic process is represented by thrombosis in preglomerular arterioles, which leads to TMA.

Acute pyelonephritis: analysis of 52 cases

Acute pyelonephritis (APN) is a frequent disease, but diagnostic approach, evolution into abscesses, and indication to hospitalization are still open problems. We have made a retrospective analysis of APN cases observed in our hospital. We identified 58 patients (pt) and selected 52 of these who presented fever and loin pain at the onset (31 were hospitalized in Nephrology and 21 in other units). Urine culture was positive in 11/48 cases (22.9%), blood cultures in 3/26 cases (11.5%) (Escherichia coli). Renal sonography was normal in 20/48 cases (41.6%) and suggestive for APN in 23/48 cases (47.9%). CT with contrast medium was normal in 9/28 cases (32.1%) and positive in 19/28 cases (67.8%), with evidence of unique or multiple hypodense areas; abscesses were found in 8 patients (28.5%). No statistically significant differences were found between patients with positive or negative CT as regards fever, leukocytosis, ESR, CRP, CRP at 20 days, urinary leukocytes, urine culture, duration of symptoms before hospitalization. Moreover no differences were found between patients with and without abscesses. CT was performed more frequently among patients hospitalized in Nephrology than among patients hospitalized in other services (24/31-77.4%-vs. 4/21-19%-, p = 0.05). NMR was abnormal in 6/9 cases. A radiographic documentation of APN was obtained in 61.53% of patients with clinical diagnosis of APN. Of these, only 18.7% had positive urine culture. In conclusion, our data suggest that demonstration of urine infection is not necessary for APN diagnosis, when clinical and/or radiologic diagnosis of APN has been made. Evolution into abscesses is frequent and not easily susceptible on clinical ground; for this reason we think it is advisable to perform CT or NMR systematically. Differences in clinical behavior between different units suggest the need for diagnostic guidelines.

[Biopsy experience at the G. Bosco Hospital from 1996 to 1999]

BACKGROUND

Aim of this study was a retrospective analysis of the renal biopsies performed in our Division.

METHODS

Since January 1, 1996 to September 30, 1999 289 biopsies were performed on native kidneys, 90 patients were older than 65.

RESULTS

The most frequent nephropathy was IgA glomerulonephritis (IgAGN) (28%), followed by membranous glomerulonephritis (MGN) (11%). In patients older than 65, the most frequent was MGN (20%), followed by IgAGN (12.2%). The total complications were 84 (29.1%) (hematomas >3 cm 1%; blood transfusion: 1.4%). Complications were not related to age, blood pressure, renal function, clinical presentation, number of shots. In 217 patients, the results obtained with two different modalities were compared: manual system (needle size=15 gauge) and automatic system (18 gauge). No statistically significant differences were found as regards the number of shots for single biopsy, number of glomeruli and major complications (1.6% vs 1.3%), while minor complications were more frequent in the second group.

CONCLUSIONS

In conclusion, the number of renal biopsies performed in our Division has been increasing year after year. This trend can be partially explained by our wider indications to renal biopsy in elderly population (the data related to resident population showed the greatest prevalence of biopsies in patients 70 to 79 years old). Renal biopsy actually represents a safe examination even in elderly patients. From a technical point of view, on the basis of personal experience, 18 gauge acecut automatic needles seem to be preferred to other kind of devices.

Report on intensive treatment of extracapillary glomerulonephritis with focus on crescentic IgA nephropathy

PURPOSE AND DESIGN OF STUDY: In this retrospective analysis the effects of combined treatment with steroid pulses, cyclophosphamide and plasma exchange on six crescentic IgA glomerulonephritis (IgAGN) patients, selected on a histological basis, were examined. The histological criteria included involvement of more than 40% of glomeruli by cellular crescents. The effects of this treatment were compared to those observed in three untreated crescentic IgAGN patients and 12 treated patients who had extracapillary glomerulonephritis of different origins, i.e. ANCA-associated systemic or renal-limited vasculitis. All patients, except the three crescentic untreated IgAGN patients, received the same 2-month treatment according to a standardized protocol: steroid boli 15 mg/kg methylprednisolone for 3 consecutive days by intravenous infusion, followed by prednisone per os (1 mg/kg/day for 4 weeks, 0.75 mg/kg/day for 4 more weeks), cyclophosphamide per os 2.5 mg/kg/day for 8 weeks, and plasma exchange.

RESULTS

After this 2-month course of therapy, substantial clinical improvement was observed in both IgAGN and vasculitis patients. However, a second biopsy revealed that florid crescents persisted in IgAGN patients and, unlike the vasculitis group, during the long-term the initial clinical amelioration disappeared in one-half of the treated IgAGN cases. Nevertheless, even in the progressive cases, intensive treatment seemed to substantially delay the onset of dialysis.

CONCLUSIONS

Despite some clinical benefits of therapy, short-term reversal of active crescents appears less likely to occur in crescentic IgAGN than in vasculitis-associated crescentic GN. Intensive treatment seems sufficient to arrest, but inadequate to reverse, phlogistic lesions in IgAGN before development of chronic changes.

Colour-coded Doppler sonography in monitoring native kidney biopsies

Two hundred and one patients had biopsies of their native kidneys with ultrasound-guided needle technique. They were evaluated on the second post-biopsy day with colour-coded Doppler sonography. Ten patients out of these 201 were found to have an arteriovenous fistula, which remained asymptomatic for the whole follow-up period (follow-ups ranged from 2 to 31 months). Four of these 10 patients developed a perirenal haematoma as well and five macroscopic haematuria. Our study shows that the systematic use of colour-coded Doppler sonography after renal biopsy facilitates diagnosis of arteriovenous renal fistula.

Indium-111-labeled granulocyte head accumulation in patients with Wegener's granulomatosis

Among the symptoms of systemic vasculitis, purulent rhinorrhea with painful sinusitis is thought to be relatively specific to Wegener's granulomatosis (WG). Sixteen patients with rapidly progressive glomerulonephritis (GN), arteritis and extensive crescents in renal biopsy were studied by head indium-111 (111In)-granulocyte scanning. They included 8 WG, 5 microscopic polyarteritis, 2 necrotizing and crescentic GN and 1 classic polyarteritis nodosa. Autologous granulocytes labeled with 12.3 MBq of 111In-oxine were administered intravenously. Scintigraphic studies were performed at 4 and 24 h post-injection. Compared to the non-WG cases, considered as a whole, significant accumulation of tracer in sinuses was observed in WG patients (Fisher's p = 0.02). Substantial scintigraphic amelioration was obtained in a WG case treated with methylprednisolone pulses and, in another WG case, after high doses of intravenous gamma-globulins. The complete disappearance of facial uptake was obtained after 2 months of intensive therapy (i.e., steroid, cyclophosphamide and plasma exchange) in another WG patient. 111In-oxine granulocyte imaging may be useful in clinical practice as an additional marker of disease activity and a tool of identification of upper respiratory tract involvement.

Urinary endothelin in glomerulonephritis patients with normal renal function

The vasoconstrictor peptide endothelin-1 (ET1) has only recently been characterized and its effects are at present largely speculative. It has been hypothesized that ET1 acts on mesangial cells to cause vasoactive changes which might ultimately contribute to the development of glomerulosclerosis. Opposite to ET1, nitric oxide (NO) inhibits mesangial cell contraction and proliferation. NO activates soluble guanylic acid cyclase and the final product, cyclic GMP (cGMP), has been recently used as a marker of NO action. Urinary levels of ET1 and cGMP were detected in 58 patients with biopsy-proven glomerulonephritis (GN), including 36 IgA nephropathy (IgAGN), 30 with normal and 6 with impaired renal function, 10 patients with non-IgA mesangial GN and 12 pts with membranous GN (MGN) with normal renal function. Compared to normal controls (0.019 +/- 0.006 ng/min), urine ET1 levels were significantly higher in patients with normal renal function having IgAGN (0.035 +/- 0.017, p < 0.01), MGN (0.028 +/- 0.013, p < 0.05), non-IgA mesangial GN (0.027 +/- 0.012, p < 0.05) and those with IgAGN and renal failure (0.032 +/- 0.011, p < 0.01). However no difference was found between MGN patients and normals by deleting MGN cases with mild to moderate mesangial proliferation. The mean value of urinary cGMP in IgAGN patients with renal failure (0.186 +/- 0.117 nmol/min) was lower (p < 0.05) than that of each group with normal renal function (IgAGN: 0.378 +/- 0.010 nM/min; MGN: 0.338 +/- 0.064 nmol/min, non-IgAGN: 0.436 +/- 0.168 nmol/min). The same significant differences were obtained by correcting cGMP values for creatinine urinary excretion. Urinary ET/cGMP ratio (assumed as an index of the relative balance between vasoconstrictor and vasorelaxing factors) was found to be higher than normal (0.570 +/- 0.010 ng/nmol) both in IgAGN patients with normal renal function (0.103 +/- 0.064 ng/mol, p < 0.05), and in those with renal failure (0.203 +/- 0.108 ng/nmol, p < 0.02). Urinary cGMP values were not related to plasma levels of atrial natriuretic peptide (ANP). These data show that hyperexcretion of ET1 occurs in a number of patients with mesangial proliferative GN. In some of them, mainly those with established glomerular damage, the local production of ET1 is not counter-balanced by adequate cGMP biosynthesis.

Removal systems of immunoglobulin A and immunoglobulin A containing complexes in IgA nephropathy and cirrhosis patients. The role of asialoglycoprotein receptors

BACKGROUND

Whereas the complex removal routes hypothesized for IgA containing immune complexes (IC) and macromolecules can be adequately analyzed by a recently proposed IgA1-IgG aggregate probe (Lab Invest, 66: 86-95), the relative significance of the asialoglycoprotein receptors in IgAIC clearance is still uncertain.

EXPERIMENTAL DESIGN

The removal kinetics of 99mTc diethylenetriamine-pentaacetic acid-conjugated asialo alpha 1 acid glycoprotein (AAGP) and 123I-labeled IgA1-IgG aggregate were analyzed in 11 cirrhosis patients and 13 IgAN patients of comparable age.

RESULTS

IgA1-IgG aggregate mean plasma clearance rate was delayed in IgA neuropathy (IgAN) patients (slope 0.038 minutes-1, range 0.027 to 0.053) compared with normals (0.047 minutes-1, range 0.038 to 0.053, p = 0.05). The liver was the main organ involved in the IgA1-IgG removal. When compared with normals, (34.3 minutes, range 29.8 to 42.2), the liver mean transit time (MTT) was significantly (p < 0.02) prolonged in IgAN patients (41.3 minutes, 33.6 to 52.3). Participation of spleen in clearance was observed in some patients and was almost invariably concurrent with normal clearance parameters. Conversely, 9 out of 11 cirrhosis patients had a remarkable splenic uptake, but the blood clearance rate was invariably delayed (0.022 minutes-1, 0.014 to 0.028, p < 0.003) and liver MTT extremely prolonged (122.4 minutes, 52.4 to 400, p < 0.003). In IgAN patients with delayed clearance of the IgA1-IgG aggregate, a distinct trend of progression towards renal failure was noted. AAGP clearance was also delayed in cirrhosis patients: slope = 0.166 minutes-1, 0.108 to 0.247, p = 0.05 as compared with both normals (0.230, 0.173 to 0.289) and IgAN patients (0.250, 0.184 to 0.254). Liver MTT in cirrhosis patients was extremely prolonged: 240.6 minutes, 132.5 to 400 minutes, p < 0.007 compared with both normals (90.0 minutes, 82.7 to 96.6) and IgA patients (92.2 minutes, 70.3 to 107.1). AAGP clearance parameters in normals and IgAN patients were not statistically different. MTT values of AAGP and IgA1-IgG aggregate were strictly related (p = 0.008), suggesting that asialoglycoprotein receptors are partially involved in the clearance of the IgA1-IgG aggregate probe.

CONCLUSIONS

Some patients with IgAN have a prolonged circulation of an IgAIC miming probe, probably due to an impaired macrophage function. Other possibilities of prolonged circulation of IgAIC in these patients should imply an abnormal IgA glycosylation pattern that allows IC to escape from an effective asialoglycoprotein receptor system. In cirrhosis patients, all of the removal routes of IgA and IgA containing IC are greatly altered suggesting a causative role in the development of an associated, often clinically inapparent, glomerular disease.

Role of monocytes in cryoglobulinemia-associated nephritis

Several monocyte-macrophage functions were found to be defective in cryoglobulinemic patients. Nevertheless, monocytes actively phagocytizing cryoglobulins have been frequently found in kidney specimens from these patients. Whether subsequent degradation of the ingested immune material is effective, however, is still unknown. Monocytes from eight cryoglobulinemic patients (4 with active disease and associated nephritis and 4 inactive cases without nephritis) and eight normal controls of same sex and similar age were analyzed. Monocytes from patients with active cryoglobulinemia and associated nephritis were found to be able to ingest, but unable to catabolize, cryoglobulins, as shown by electron microscopy using gold-labeled goat IgG to human IgG and IgM in 18-hour cultured suspensions. Synthesis and maturation of monocyte cathepsin D, one of the most important lysosomal proteases, were analyzed in the same subjects. Purified monocytes were cultured in presence or absence of cryoglobulins for 18 hours at 37 degrees C in RPMI medium and labeled with 35S-methionine. The various forms of cathepsin D were separated by electrophoresis and visualized by fluorography. Results from cultures of monocytes from clinically active cryoglobulinemic patients with nephritis suggest that intracellular transport of newly synthesized cathepsin D was impaired and the release into the medium of precursor polypeptides of the enzyme enhanced in each experimental condition. Since procathepsin D is susceptible to activation in pathologic conditions lowering local pH (such as in inflamed tissues), these data suggest that monocytes from patients with active cryoglobulinemia and associated nephritis have a propensity to exert phlogistic effects via secretion of procathepsin D in tissues.

Serum and intracellular detection of cytokines in patients undergoing chronic hemodialysis

Tumor necrosis factor (TNF) was detected, before and after dialysis, in sera from 69 patients and, at various times during dialysis, in 28 patients carefully selected for the absence of intercurrent illness. Blood samples were also sequentially collected for separation of monocytes, and cells were sonicated to detect intracellular TNF. Compared with serum levels obtained from 41 healthy subjects, basal TNF values of the unselected group of 69 patients were significantly higher (p < 0.01), independent of the dialyzer membrane. A significant increase in TNF levels by the end of dialysis was found only with Cuprophan (p < 0.01). In the selected group of 28 patients, no significant changes in TNF values were observed in sequential samples. However, a significant increase of intramonocyte TNF levels was found in Cuprophan patients (p < 0.025). Soluble interleukin-2 receptor (IL-2R) levels, measured in parallel in sera from unselected and selected patients, were found to be very much higher than healthy controls without significant changes during the dialysis procedure. While the diverse profiles of TNF obtained from differently selected patients suggest that mechanisms other than membrane biocompatibility play a role in the appearance of these low cytokine levels, the possible nature of uremic toxin for soluble IL-2R can be envisaged by detection in dialysis patients.

Kinetics and fate of IgA-IgG aggregates as a model of naturally occurring immune complexes in IgA nephropathy

The characteristic granular IgA immunofluorescent pattern in the kidneys of IgA nephropathy patients is consistent with immune complex pathogenesis. The possibility of a delayed clearance of IgA-containing immune complexes from circulation in IgA nephropathy patients is still under discussion. Since pure IgA immune complexes are probably nonphlogistic, (in contrast to IgG-containing IgA immune complexes), the in vivo clearance of a mixture of heat-aggregated IgA/G purified from pooled human sera was analyzed. The test probe was efficiently labeled with 123I and the time course of radioactivity was measured by a gamma-camera. Both the liver and the spleen were found to be involved in the disappearance of IgA/G complexes. Liver accumulation, which was markedly predominant, closely approximates a gamma-variate function which allowed determination of a mean transit time of 34.37 minutes, range 29.8 to 42.2, in 8 normal and 37.54 minutes, range 30.9 to 50.7 in 17 patients (p less than 0.04). At 2 hours, segmental gut accumulation was found, which demonstrated removal by hepatobiliary system as well. Compartmental analysis in patients indicated 3 major compartments represented by vascular bed, hepatobiliary and reticuloendothelial systems (including both liver and spleen phagocytes). Blood clearance rate, representing the final result of multiorgan removal of the test probe from the blood stream, was found to be significantly delayed in IgA nephropathy patients with a slope (0.035 min-1, range 0.019 to 0.052) significantly less negative compared with controls (0.047 min-1, range 0.038 to 0.053, p less than 0.01). This test probe was able to reproduce both removal routes (macrophages cells and hepatobiliary system) hypothesized for IgA-containing immune complexes in humans.