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Claudio Ponticelli

Publications and source records attributed to Claudio Ponticelli.

51 records · Page 3Linked to original sources
PubMed2002

Long-term prognosis of diffuse proliferative glomerulonephritis associated with infection in adults.

BACKGROUND: Infection-associated glomerulonephritis is rare in adults and its long-term prognosis is undefined. METHODS: We retrospectively evaluated the clinical course of 50 adults (30 men, 20 women) with infection-associated glomerulonephritis diagnosed in our department from 1979 to 1999. The mean follow-up was 90+/-78 months. Patients were subdivided into two groups: group 1 included those without underlying disease and group 2 included those with severe underlying disease. RESULTS: At presentation, the median age was 54 years, and 33 patients were hypertensive, 31 had nephritic syndrome, eight had nephrotic syndrome and 11 had non-nephrotic proteinuria. Patients in group 2 were significantly older and had a significantly higher proteinuria than patients of group 1. Of the 21 patients in group 2, nine had liver cirrhosis, four cancer, five diabetes, three bronchiectasis, one thalassaemia intermedia, one polymyositis and one had anti-phospholipid antibodies syndrome. At the last follow-up, five patients had died, 21 patients were in complete remission, ten had partial remission, ten had renal insufficiency and three were on chronic dialysis. Multivariate analysis showed that an underlying disease (P=0.04) and interstitial infiltration at biopsy (P=0.036) were predictors of incomplete recovery. A correlation analysis between the year of diagnosis and the clinical/ histological characteristics at presentation showed that age (P=0.05), atypical infections (P=0.01), underlying disease (P=0.01) and interstitial infiltration at biopsy (P=0.02) increased over time, while the number of patients with complete remission significantly decreased (P=0.001). CONCLUSIONS: Infection-associated glomerulonephritis may progress to chronic renal failure in a consistent number of adult hospitalized patients, particularly in those with an underlying disease and when associated with interstitial infiltration at biopsy.

Adult↗
PubMed2002

Role of anaemia in cardiovascular mortality and morbidity in transplant patients.

Cardiovascular complications are a major cause of morbidity and the leading cause of mortality in renal transplant recipients. Multiple cardiovascular risk factors are often present before transplantation. Prior ischaemic heart disease, cerebrovascular disease and peripheral vascular disease predict post-transplantation mortality, as do older age, diabetes mellitus, smoking and length of time on dialysis. After transplantation, immunosuppressive agents and/or graft dysfunction may increase cardiovascular risk by causing hypertension, hyperlipidaemia and diabetes mellitus or glucose intolerance. Graft dysfunction may also contribute to cardiovascular risk by causing anaemia or hyperhomocysteinaemia. To assess the relative importance of potential cardiovascular risk factors in renal transplant recipients, a retrospective analysis has been performed on data from 911 patients at the Ospedale Maggiore, Milan, Italy. Preliminary findings confirm that cardiovascular complications are the leading cause of death in renal transplant recipients, accounting for 32% of all deaths. Other major factors predicting post-transplantation cardiovascular events include pre-transplant cardiovascular events, age, smoking, diabetes mellitus (often acquired after transplantation) and hypertension. Careful selection and adequate preparation of patients in addition to appropriate treatment of cardiovascular risk factors are needed before transplantation to reduce the risk of post-transplantation cardiovascular events. After transplantation, appropriate treatment of diabetes, hypertension and hyperlipidaemia, as well as avoidance of smoking, obesity and physical inactivity may reduce the risk of cardiovascular complications further.

Anemia↗
PubMed2002

Calcium and phosphate plasma levels in dialysis patients after dietary Ca-P overload. Role of gastric acid secretion.

In normal subjects, the gastric ionisation of calcium and phosphate seems to be a prerequisite for their intestinal absorption. We investigated the behavior of the plasma calcium and phosphate profile in 30 patients on regular dialysis treatment in the 6 h following a meal containing 1 g of calcium and 2 g of phosphate. Moreover, to assess the role of gastric acidity, the study was repeated after 3 days on omeprazole administration, to nearly abolish gastric acid secretion. Both total plasma calcium and ionized calcium peaked after the meal (at 30 and 120 min, respectively) only in basal study, while no peak was observed after the administration of omeprazole. Surprisingly, both in basal and in the omeprazole study the levels of plasma phosphate did not increase after the test meal. In conclusion, as in normal subjects, the gastric ionization of dietary calcium promotes the intestinal absorption of calcium in uremic patients on dialysis treatment, while the acute gastric acid inhibition by omeprazole reduced the intestinal calcium transport. In contrast, with the "trade off" hypothesis we did not observe any postprandial phosphate peak after the dietary load, and, in contrast with normal subjects, omeprazole administration did not influence the phosphate profile.

Adult↗
PubMed2002

Kidney and liver involvement in cryoglobulinemia.

Cryoglobulinemia is a pathological condition characterized by the presence in the blood of a group of proteins (cryoglobulins) showing the common property of precipitating from cooled serum. Mixed cryoglobulins (MCs) are composed of a polyclonal immunoglobulin G (IgG) bound to another immunoglobulin that acts as an anti-IgG rheumatoid factor; 2 types of MCs can be identified. The origin is not clear in 30% of all MCs, and this subset of cryoglobulinemias is called "essential." The great majority (up to 90%) of patients with essential MC (EMC) of both types has been related to HCV infection. The renal involvement in essential MC has been observed in 2% to 50% of patients in reported series. A well-characterized pattern of glomerular disease termed "cryoglobulinemic glomerulonephritis" is present in individuals with type-II EMCs in serum and IgMk RF being the most frequent monoclonal component. Aspecific and infrequent glomerular lesions occur in EMC patients with type III cryoglobulins. The most frequent histologic picture of cryoglobulinemic GN is that of membranoproliferative GN (MPGN) with subendothelial deposits. However, cryoglobulinemic GN may have some distinctive features that differentiate it from idiopathic type-I MPGN. Evidence of liver involvement has been found in 60% to 80% of EMC patients. Recent data support the notion that the stage of liver disease in patients with type II or III MC has association with the prevalence of cryoglobulinemia. Few controlled trials have been published on the treatment of HCV-related MC; in addition, the majority of the patients enrolled in these trials had an unclear renal involvement. Interferon (IFN) is an effective drug for the treatment of patients with HCV-associated MC and cryoglobulinemic GN. In the presence of acute cryoglobulinemic GN, IFN does not prevent progression of renal damage; combination therapy with cytotoxic ad anti-inflammatory drugs, and sometimes plasma exchange, is recommended. Prospective controlled trials are underway on this purpose.

Antiviral Agents↗
PubMed2001

Long-term results of a randomized study comparing three immunosuppressive schedules with cyclosporine in cadaveric kidney transplantation.

In this randomized controlled trial started in October 1990, 354 cadaveric kidney transplant recipients were assigned to receive either cyclosporine (CsA) monotherapy (115 patients), CsA + steroids (117 patients), or CsA + steroids + azathioprine (122 patients). The median follow-up was 85.1 mo. Thirty-one deaths occurred (infection, 12; cardiovascular disease, 11; neoplasia, 4; and others, 4), and 65 grafts were lost, mostly due to acute (15) or chronic rejection (50). The cumulative graft half-life was 18.1 yr. According to the "intention-to-treat," the 9-yr actuarial patient and graft survival were 94.0% and 73.3%, respectively, in monotherapy, 87.3% and 65.9% in dual therapy, and 87% and 72.2% in triple therapy (P = 0.647). At the last follow-up, the percentage of patients who remained with the original treatment was 51.2% in monotherapy, 81.7% in dual therapy, and 63.3% in triple therapy. At the seventh year, the mean creatinine clearances were 54.9 +/- 17.6 ml/min in monotherapy, 57.9 +/- 23.4 in dual therapy, and 60.6 +/- 20.7 in triple therapy (P = 0.375). Cataracts (P = 0.000), osteoporosis (P = 0.000), and cardiovascular complications (P = 0.000) were more frequent in dual or triple therapy than in monotherapy. Actuarial graft survival at 9 yr in patients on monotherapy who had to have steroids added was similar to that of the other two groups (62.2% versus 69.3%, P = 0.134). In conclusion, actuarial patient and graft survivals did not differ among the three schemes. The long-term renal function and survival were not affected in the patients on monotherapy who needed the addition of steroids. Monotherapy was associated with a lower incidence of extrarenal complications than the other two regimens.

Adolescent↗
PubMedDate not supplied

BK polyomavirus interstitial nephritis in a renal transplant patient with no previous acute rejection episodes.

A renal transplant patient treated with tacrolimus and mycophenolate-mofetil (MMF) developed progressive graft function deterioration 10 months after transplantation. Biopsy of the graft showed severe, focally accentuated interstitial inflammation with focal tubulitis and tubular necrosis, and medium-severe interstitial fibrosis with focal tubular atrophy. Glomerular and vascular structures were preserved. On careful examination, in some sections, tubular epithelial cells showed a definite increase with deformation of the nuclear shape, chromatin irregularities with peripheral dislocation and inclusion bodies. These cytopathic changes suggested polyoma virus infection ("decoy cells"). Subsequent screening of the urinary sediment confirmed the presence of many "decoy cells". Immunohistochemical analysis of the biopsy showed many tubular cells were strongly positive for the SV 40 antigen, specific for BK polyoma virus. A diagnosis of interstitial nephritis due to BK polyoma virus was made, though the coexistence of cellular rejection could not be excluded. At variance with previous reports, our patient had not had repeated episodes of rejection before biopsy or heavy immunosuppressive treatment, such as ALG, OKT3, after transplantation. This case shows that even in the absence of vigorous anti-rejection therapy an immunosuppressive regimen based on tacrolimus and MMF may involve the risk of BK polyoma virus- associated interstitial nephritis.

Adult↗
PubMedDate not supplied

Epidemiology of GB virus c/hepatitis g virus infection in patients on peritoneal dialysis.

BACKGROUND: A new genus in the family Flaviviridae has recently been discovered; it has provisionally been designated GBV-C/HGV. As determined by virologic techniques [reverse-transcription polymerase chain reaction (RT-PCR)], infection with GBV-C/HGV is frequent in renal transplant (RT) recipients and in patients on chronic hemodialysis (HD). The epidemiology of GBV-C/HGV infection in patients on peritoneal dialysis is scarce and mostly based on RT-PCR technology. PURPOSE: We report on the prevalence (as detected by serologic and virologic techniques) and the risk factors for GBV-C/HGV infection in a cohort of patients on continuous ambulatory peritoneal dialysis (CAPD). We also tested a control group of blood donors. METHODS: Infection by GBV-C/HGV was assessed by serologic and virologic techniques. Cases of GBV-C/HGV viremia (GBV-C/HGV RNA) were detected by RT-PCR. Antibodies to the envelope protein of GBV-C/HGV (anti-E2 GBV-C/HGV antibody) were analyzed by serologic methods. RESULTS: We found a high frequency [17/85 (20%)] of GBV-C/HGV. The rates of GBV-C/HGV viremia and anti-E2 GBV-C/HGV positivity were 10.5% (9/85) and 10.5% (9/85) respectively. In most patients [17/18 (94%)], the presence of anti-E2 GBV-C/HGV antibody was associated with clearance of GBV-C/HGV from serum. No relationship was noted between anti-E2 GBV-C/HGV antibody (or GBV-C/ HGV viremia) and age, sex, race, time on dialysis, anti-HCV antibody, HBsAg status, and anti-HIV positivity. The frequency of GBV-C/HGV infection in CAPD patients was much higher than that in blood donors, even if the difference did not approach statistical significance. No associations between GBV-C/HGV positivity and biochemical liver tests [aminotransferase and gamma glutamyl transpeptidase (GGT)] were apparent. CONCLUSIONS: Infection by GBV-C/HGV as detected by RT-PCR and anti-E2 antibody was common in patients on CAPD and in controls alike. No association was seen between GBV-C/HGV and various demographic or clinical factors. The clinical significance of GBV-C/HGV in CAPD remains unclear. Larger investigations are in progress.

Aged↗
PubMedDate not supplied

The risk of pregnancy in patients with lupus nephritis.

Since many women with systemic lupus erythematosus (SLE) are of child-bearing age and have normal fertility, the clinician must often face many problems relating to pregnancy in patients with lupus nephritis. These include the influence of lupus nephritis on fetal outcome, obstetric complications, and the influence of pregnancy on SLE. Studies published in the 1960s underlined the increased fetal and maternal risk and recommended against pregnancy in lupus patients. The prognosis for non-pregnant SLE active patients was also poor, making it difficult to know whether pregnancy altered the prognosis of the disease. Recent prospective studies indicate that the majority of lupus mothers can sustain pregnancy without detrimental effects, providing that the pregnancy is planned during the inactive phase of the disease. Nevertheless the fetal risk, although progressively reduced during the last 40 years, continues to be higher than in pregnancies of healthy women particularly in patients with antiphospholipid antibodies.

Embryonic and Fetal Development↗
PubMedDate not supplied

Successful treatment of hemolytic uremic syndrome after liver-kidney transplantation.

INTRODUCTION: Hemolytic-uremic syndrome (HUS) is a rare complication in organ transplantation, characterized by hemolytic microangiopathic anemia, thrombocytopenia, and severe renal failure. The syndrome is a well-recognized complication in bone marrow transplantation, and has been likewise described in several cases of solid organs transplantation, but never in patients receiving combined liver and kidney transplantation. CASE REPORT: We describe a case of HUS in a 59-year-old woman who underwent combined liver-kidney transplantation for hepato-renal polycystic disease. Clinical and laboratory manifestations of the syndrome were severe and included renal failure, hemolytic anemia, severe thrombocytopenia, hypertension, and neurological damage. The initial treatment consisted of withdrawal of cyclosporine, introduction of low-dose tacrolimus, and administration of fresh frozen plasma (FFP) transfusion and heparin. Since there was no improvement in clinical or biochemical features, plasmapheresis with FFP replacement (2000 mL/day) followed by intravenous immunoglobulin (0.4 mg/Kg/day) was started. A rapid improvement in renal function, platelet count, and hemolytic anemia was observed. CONCLUSIONS: Based on the good response observed in our patient, we feel that an aggressive treatment with plasmapheresis and intravenous immunoglobulin should be offered to organ transplant recipients with severe HUS.

Combined Modality Therapy↗
PubMedDate not supplied

Altruistic living renal transplantation.

Living donor renal transplantation can not only reduce the increasing gap between demand and supply of renal transplants, but when compared with cadaveric renal transplants can also allow better results, particularly in the long-term. With the exception of HLA-identical siblings, there are no differences in long-term graft survival between HLA-related and HLA-unrelated living donor transplants. The possibility of a early transplantation, ideally before dialysis, can strongly improve patient and graft survival. The post-operative mortality and morbidity of the donor are minimal and may be furtherly reduced by an appropriate work-up. At present, there is no evidence that mononephrectomy in healthy subjects can expose them to an increased risk of renal failure, even in the long-term.

Cadaver↗
PubMedDate not supplied

Renal replacement therapy in lupus nephritis.

The indications and the choice of renal replacement therapy for lupus patients are similar to those for other uremic patients. However, lupus patients can pose some particular problems. First, 10-28% of patients needing dialysis can have a partial renal function recovery. Therefore, the clinician has to decide whether to administer a rescue treatment, risking side-effects, or to reduce immunosuppression precluding a potential recovery. Many patients on regular dialysis show subdued biological and clinical activity. Others can show a hectic disease activity, particularly in the 1st year. In these cases, treatment is difficult, as vigorous immunosuppression can expose uremic patients to severe side-effects. The presence of circulating antiphospholipid antibodies (aPL) can favor thrombosis or stenosis of vascular access (VA). Renal transplantation is the best therapy for most lupus patients with end-stage renal failure. Many, but not all, studies have reported similar patient and graft survival rates in lupus and in non-lupus transplant recipients. The results are much better with living donor transplantation. Patients with aPL, black patients and those on long-term dialysis have a higher graft failure risk. Candidates with active lupus and/or those with significant iatrogenic morbidity should be advised to wait 6-12 months before transplantation. The recurrence risk of lupus nephritis ranged between 2% and 30% in different studies. The histological picture does not usually show severe features. Antiplatelet agents or anticoagulation can be advised for aPL patients.

Humans↗
PubMedDate not supplied

The pleiotropic effects of mTor inhibitors.

mTOR is a downstream effector of phosphatidylinositol-3-kinase pathway, which is involved in the regulation of protein synthesis and interacts with cell cycle progression. Sirolimus and everolimus may interfere with mTOR activity after their binding with FK binding protein. These drugs may prevent rejection of organ transplants by inhibiting the proliferation signals provided by interleukins 2 and 15, so causing lymphocyte cycle arrest in the G1 phase. Experimental studies have also shown that some oncoproteins may derive either from an overactivity of phosphatidylinositol-3-kinase or from a loss of the tumor suppressor PTEN. As mTOR is an important mediator of the kinase cascade and may also be antiangiogenic, it has become an attractive target in some malignancies. In organ transplant recipients some retrospective studies have shown that patients treated with mTOR inhibitors for immunosuppression had a reduced incidence of neoplasia in comparison with patients treated with calcineurin inhibitors. mTOR is also involved in the replication of cytomegalovirus in the host cells, as it favors transcription and translation signals necessary for virus replication. Recent studies reported a very low incidence of cytomegalovirus infection in organ transplant patients treated wih either sirolimus or everolimus. Finally, mTOR inhibitors may offer vascular protection, as they mediate vascular endothelial growth factor. In cardiac transplants treated with everolimus, cyclosporine, and steroids the average increase in maximal intimal thickness and the incidence of vasculopathy were significantly lower than in patients treated with azathioprine, cyclosporine, and steroids.

Animals↗
PubMedDate not supplied

Generic cyclosporine: a word of caution.

Cyclosporine (CsA) has been the cornerstone of immunosuppression for organ transplantation since its introduction. However, CsA is a critical drug as it has low therapeutic index and high inter- and intra-individual variations in bioavailability. The new microemulsion Neoral has increased bioavailability and is not influenced by bile or food. When compared with the old formulation, Neoral was able to significantly reduce rejection and to allow a better long-term graft survival in renal transplant patients. Moreover, the measurement of CsA at peak, around 2 hours after Neoral administration, proved to be a reliable index of the drug exposure, thus allowing efficient drug monitoring. Recently, different CsA galenics have been approved on the basis of bioequivalence tests performed in a small number of healthy volunteers after a single administration. Transplant experts expressed their concern about the adequacy of these tests in organ transplantation. The few short-term studies of bioequivalence in renal transplant recipients reported conflicting results. Certainly, the bioequivalence tests used, cannot capture a subset of low-absorbers who are exposed to the risk of underimmunosuppression. Another matter of concern is the lack of studies with galenic CsA to evaluate the role of C2 measurement for therapeutic drug monitoring. Observational studies reported a lower 1-year renal allograft survival in patients treated with galenic CsA than in patients given Neoral. A main problem is the absence of long-term studies with generic CsA, in the complex setting of organ transplantation.

Cyclosporine↗
PubMedDate not supplied

Neurological complications in kidney transplant recipients.

Neurological complications are frequent in renal transplant recipients and may largely contribute to morbidity and mortality. The postransplant neurological complications may be categorized into five areas: 1) Immunosuppressive medications, 2) stroke, 3) peripheral neuropathies, 4) infection, and 5) malignancies. A number of complications are directly caused by the neurotoxicity of immunosuppressive agents. Calcineurin-inhibitors may cause mild symptoms, such as tremors and paresthesia, or severe symptoms, such as disabling pain syndrome and leukoencephalopathy. Severe neurological syndromes may also be caused by the monoclonal antibody OKT3. Stroke may occur in about 8% of renal transplant patients. It may be favored by hypertension, diabetes, and accelerated atherosclerosis which may be acquired during dialysis or after transplantation. Peripheral mononeuritis and polyneuritis may also occur. An acute femoral neuropathy may occur in about 2% of patients as a result of nerve compression after operation. Guillain-Barré syndrome may also develop, triggered in some cases by cytomegalovirus (CMV) or Campylobacter jejuni infection. Lymphomas are the most frequent brain tumors. They are usually associated to a Epstein Barr virus (EBV) infection and are more frequent in patients who received an aggressive immunosuppressive therapy. Infection represents the most frequent neurological complication. Acute meningitis usually caused by Listeria monocytogenes, subacute and chronic meningitis caused by Cryptococcus neoformans, focal brain infection caused by Aspergillus fumigatus, Toxoplasma gondii or Nocardia asteroids, and progressive dementia caused by polyoma J virus or other viruses are the most frequent types of neurological infections.

Adrenal Cortex Hormones↗