Foto del docente

Olga Baraldi

Senior assistant professor (fixed-term)

Department of Medical and Surgical Sciences

Academic discipline: MEDS-08/B Nephrology

Research

1. Immune mediated glomerulonephritis

2. New insight in artificial renal replacement treatments: automatic adaptive system dialysis for hemodialysis-associated hypotension and disequilibrium symptoms

3. Restless-leg sindrome in uremia

4. Substitution treatment of liver function: application of MARS (Molecular Adsorbent Recirculating System)

5. Kidney transplant: immunological aspects, cardiovascular risk factors and gene polymorphism

 

1. Glomerulonephritis refers to a group of relatively rare immune-mediated diseases characterized by lesions that primarily affect the renal glomeruli. If not properly treated, glomerulonephritis can progress to chronic kidney disease, leading to irreversible renal failure. According to data from US Medicare (with an average age of 75 years), approximately 1.2% of individuals are affected by these nephropathies. Certain forms of glomerular nephropathies are more prevalent and severe in specific ethnic groups, such as African-American, Hispanic, and Asian populations.

Traditionally, glomerulonephritis is classified based on typical histopathological lesions observed in renal biopsies, which remain the gold standard for assessing disease activity and chronicity. However, in recent years, advances in the understanding of pathogenetic mechanisms have led to new classification proposals. The increasing availability of immunomodulatory drugs has enabled more modern and effective treatment approaches. In addition, expanded genetic testing using next-generation sequencing has emerged as a valuable diagnostic tool for providing precise molecular diagnoses.

Renal biopsy continues to play a crucial role in diagnosis and remains the gold standard for determining disease activity and chronicity. Moreover, new urinary biomarkers of immunological activity during glomerulonephritis are now being used to monitor treatment responses.

In this context, IgA nephropathy (IgAN) is the most widespread glomerular disease globally, where complement activation plays a key role in its pathogenesis. Specifically, considering the prognostic value of serum complement levels at the time of diagnosis in IgAN patients may help assess the progression of chronic kidney disease (CKD). One study evaluated 101 patients with IgA nephropathy, stratified by baseline C3 levels into three groups (low, medium, and high), and found, after a median follow-up of 54 months, that the low C3 group had a higher incidence of chronic kidney disease. Therefore, incorporating serum C3 and C4 values into the overall assessment of IgAN patients may enhance the accuracy of predicting kidney disease progression.

 

2. New insight in artificial renal replacement treatments: automatic adaptive system dialysis for hemodialysis-associated hypotension and disequilibrium symptoms

Hemodialysis is complicated by a high incidence of intradialytic hypotension and disequilibrium symptoms caused by hypovolemia and a decrease in extracellular osmolarity. Automatic adaptive system dialysis (AASD) is a dialysis system that provides automated elaboration of dialysate and ultrafiltration profiles based on the prescribed decrease in body weight and sodium content.

A non-controlled (single arm), multicenter, prospective, clinical trial has been carried out on 55 patients with intradialytic hypotension or disequilibrium syndrome in 15 dialysis units. The patients were studied over a 1-month interval using standard treatment (642 sessions) followed by 6 months using AASD (2,376 sessions).

More stable intradialytic systolic and diastolic blood pressures with lower heart rate were found using AASD compared with standard treatment. Sessions complicated by hypotension decreased from 58.7% ± 7.3% to 0.9% ± 0.6% (P < 0.001). The incidence of other disequilibrium syndrome symptoms was lower in patients receiving AASD. This study shows the long-term clinical efficacy of AASD for intradialytic hypotension and disequilibrium symptoms in a large number of patients and dialysis sessions.

 

3.  Restless-leg syndrome in uremia

Restless legs syndrome (RLS) is a sleep-related movement disorder involving an urge to move the legs frequently in association with unpleasant sensory symptoms. RLS can occur in 2 forms: idiopathic or secondary to other conditions including end-stage renal disease. RLS is highly prevalent in patients on maintenance dialysis and ESRD patients with sleep disorders which are independently linked to a higher mortality rate. We evaluated the impact of chronic inflammation on RLS in dialysis patients. 100 patients in dialysis for at least 3 months were included in this study. A specific questionnaire based on the criteria of the International Restless Legs Syndrome Study Group (IRLSSG) was used to asses the prevalence of RLS. Gender, age on starting dialysis, time on dialysis, BMI, blood pressure, tobacco use, comorbidities and drugs were recorded. The basal values of hemoglobin, hematocrit, CRP, PTH, calcium, phosphorus, albumin, alkaline phosphatase, total-, HDL- and LDL-cholesterol, triglycerides, uric acid, fibrinogen, erythrocyte sedimentation rate (ESR), iron, ferritin, transferrin, electrolytes were assayed in each patient. RLS was observed in 31/100 (31%). Univariate analysis revealed positive correlations between RLS and female gender (p=0.048), polyneuropathy (p=0.031), fibrinogen (p=0.004), ESR (p=0.004), CRP (p=0.025), white blood cells (WBC) (p=0.023), albumin (p=0.018). After adjustment for age, dialysis vintage, gender and Charlson score, multivariate analysis showed that CRP (p=0.041), fibrinogen (p=0.002), ESR (p=0.005), albumin (p=0.026) and WBC (p=0.022) were significant independent predictors for RLS. This study revealed a higher prevalence of RLS in dialysis patients, thus suggesting a role in the pathogenesis of RSL of chronic inflammation, besides the well-known associations with atherosclerosis, malnutrition, longer hospitalizations and cardiovascular mortality (La Manna G, et al. Restless legs syndrome enhances cardiovascular risk and mortality in patients with end-stage kidney disease undergoing long-term haemodialysis treatment. Nephrol Dial Transplant. 2010 Nov 5).


4. Substitution treatment of liver function: Application of MARS (Molecular Adsorbent Recirculating System)

An important research line is the application of Molecular Adsorbents Recirculating regards the System (MARS) in the treatment of liver failure. The principle of this method is based on the use of an extracorporeal circuit similar to that of hemodialysis, combined with an albumin circuit. This allows to remove from the blood not only free toxins, but also the albumin-bound toxins (bile acids, aromatic compounds, bilirubin, mercaptans, ammonia, lactic acid). This study was focused on the effectiveness of treatment in 22 patients with acute liver failure and acute on chronic liver failure, with the aim to assess not only of the patients' clinical situation, but also the efficiency of the MARS circuit in the removal of bilirubin, ammonia, bile acids and urea, the indices of biocompatibility, the acid-base balance and electrolyte. We have also measured plasma levels of inflammatory cytokines (IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, TNF-alpha, IFN-gamma) and major hepatic growth factors (EGF and HFG) pre-and post-MARS treatment in order to analyze the effects on inflammation and liver regeneration.

 

5. Kidney transplant: immunological aspects, cardiovascular risk factors and gene polymorphism

Cardiovascular disease (CVD) represents the main cause of morbidity and mortality after renal transplantation. A pathogenetic link between inflammation, atherosclerosis and CVD have been demonstrated. For this reason, genetic factors regulating cytokine production and the balance between pro- and anti- inflammatory molecules could have a deep influence on CVD risk. In the view of the modern paradigm of atherosclerosis as an inflammatory disease, the present study was undertaken to investigate the impact of inflammatory cytokine polymorphisms on post-renal transplant CVD. To evaluate the association between cytokine polymorphisms and CVD, a case-control study was carried out on 798 renal allograft recipients transplanted between 1997 and 2008, 196 of them with CVD (CVD group) and 602 controls free of cardiovascular complications (no-CVD group). TNF-α/G-308A, TGF-β1/L10P, TGF-β1/R25P, IL-10/G-1082A, IL-10/C-819T, IL-10/C-592A, IL-6/G-174C, IFN-γ/T+874A, IL-8/T-251A and VEGF/C+936T polymorphisms were genotyped using PCR-SSP and RFLP. The patients in CVD and no-CVD group differed significantly in IL-10 and TNF-α genotype frequency. Using multivariate analyses to test the association with CVD, the high producer genotype of the pro-inflammatory cytokine TNF-α was significantly associated with a 4.41-fold increased cardiovascular risk. Conversely, the carriage of high producer genotype of the anti-inflammatory cytokine IL-10 resulted protective against post-transplant CVD, with an adjusted OR of 0.2 (0.02-0.29). This work seems to indicate that gene polymorphisms involved in inflammatory response might represent cardiovascular risk markers in renal allograft recipients and suggests a prognostic value of TNF-α and IL-10 genotypes. Further studies are necessary to evaluate if patients with a CVD "predisposing" genotype should be treated more aggressively (La Manna G, Cappuccilli ML, Capelli I, Baraldi O, Cuna V, Battaglino G, Feliciangeli G, Dormi A, Scolari MP, Stefoni S. The impact of apoptosis and inflammation gene polymorphisms on transplanted kidney function. Ann Transplant. 2013 Jun 4;18:256-64.)

                                 

Latest news

At the moment no news are available.