From kidney to cardiovascular diseases: NGAL as a biomarker beyond the confines of nephrology.

Neutrophil gelatinase-associated lipocalin (NGAL), a small 25 kDa stress-protein released from injured tubular cells after various damaging stimuli, is already known by nephrologists as one of the most promising biomarkers of incoming Acute Kidney Injury. Moreover, recent studies seem to suggest a potential involvement of this factor also in the genesis and progression of chronic kidney diseases. This brief review explores the new interesting involvement of NGAL in the experimental and clinical field of cardiovascular diseases, such as the pathogenesis and clinical manifestations of atherosclerosis, acute myocardial infarction and heart failure. It does not seem difficult that, in the next future, NGAL may become a new missing link between the kidney and the cardiovascular system.

Acute cardiovascular complications of hemodialysis.

In patients with chronic renal failure undergoing dialysis the mortality rate from cardiovascular conditions is 10 to 100 fold than in general population. The higher mortality rate is due not only to the influence of traditional risk factors, such as hypertension, diabetes, obesity, dyslipidemia and cigarette smoking, but also to specific factors of uremic patients. Acute complications commonly take place during routine hemodialysis treatments (HD) due to unsteadiness in the cardiovascular system balance. We will review most important cardiovascular complications during HD from hypotension to ventricular hypertrophy, from arrhythmias to sudden death, and finally myocardial ischemia. A large number of structural and functional peripheral vascular and cardiac abnormalities including electrolyte imbalance, hemodynamic instability and neuro-humoral stress exert an overwork on myocardium and lead to occurring of a single cardiovascular complication but are always strictly correlated events.

The erythropoietin and regenerative medicine: a lesson from fish.

BACKGROUND: Erythropoietin (EPO), the main haematopoietic growth factor for the proliferation and differentiation of erythroid progenitor cells, is also known for its angiogenic and regenerative properties. MATERIALS AND METHODS: In this study, we aimed to test the regenerative effects of EPO administration in an experimental model of Sea bass (Dicentrarchus labrax) subjected to amputation of the caudal fin. RESULTS: Erythropoietin-treated fishes (3000 UI of human recombinant EPO-alpha immediately after cutting and after 15 days) showed an increased growth rate of their fins compared with those untreated (anova variance: P: 0.01 vs. P: 0.04). By analysing fin length at established times (15 and 30 days after cut), EPO-treated fishes always showed an increased length compared with untreated ones (T-15: 1.1 +/- 0.2 vs. 0.7 +/- 0.2 cm, P: 0.03; T-30: 1.9 +/- 0.3 vs. 1.2 +/- 0.2 cm, P: 0.01). Moreover, exogenous EPO administration induced an enormous increase in EPO-blood levels at each observation time (T-15: 2240 +/- 210 vs. 16.7 +/- 1.8 mU mL(-1), P < 0.001; T-30: 2340 +/- 190 vs. 17.1 +/- 1.9 mU mL(-1), P < 0.001), whereas these levels remained quite unmodified in untreated fishes. Immunochemical analyses performed by confocal laser scanning microscopic observations showed an increased expression of EPO-receptors and PECAM-1 (an endothelial surface marker of vessels sprout) in the regenerating tissue, whereas no signs of inflammation or fibrosis were recognisable. CONCLUSIONS: All these findings confirm EPO as a new factor involved in regenerative processes, also suggesting a potential, future utility for new therapeutical applications in the field of human regenerative medicine.

A case-by-case protocol of membranous nephropathy treatment with endovenous infusion of high doses of human immunoglobulins.

The treatment of membranous nephropathy is a highly controversial issue. As some patients may have spontaneous remission, in about 50% of cases the risk of treating patients with drugs that may have severe side effects is higher than the potential benefit of arresting disease progression. Some authors therefore propose exclusively symptomatic treatment; other authors use steroids and immunosuppressive drugs, alone or in association with high risk of adverse effects and often uncertain benefits. The intravenous administration of high doses of human immunoglobulins (IVIg) has been also extended to a growing number of kidney diseases including membranous nephropathy. The mechanisms through which IVIg carry out their therapeutic effect are still unclear. The present study is a retrospective and uncontrolled trial, the aim of which was firstly to verify if some patients could respond to extremely short treatment protocols, stopped when they appear to have a stable remission, thereby avoiding expensive continuation of treatment. Secondly, we aimed to verify if some patients, judged as nonresponders to a classical protocol of IVIg therapy, could respond to a more prolonged treatment.

[Alexithymia and immunoendocrine parameters in patients affected by systemic lupus erythematosus and rheumatoid arthritis]. / Alessitimia e pathway immunoendocrino nel lupus eritematoso sistemico e nell'artrite reumatoide.

OBJECTIVE: Aim of this study was to evaluate the prevalence of alexithymia in patients affected by SLE or RA and to investigate the correlation between alexithymia and immunoendocrine parameters (PRL, hGH, IL-6 and TNF-alfa). METHODS: Twenty-five patients (12 and 13 affected by SLE and RA, respectively) were enrolled into the study. The Toronto Alexithymia Scale-20 (TAS-20) was administered. PRL, hGH, IL-6 and TNF-alfa levels were measured by commercially available ELISA kits. RESULTS: Alexithymia prevalence (TAS-20 > or = 51) was 54% in RA and 42% in SLE patients. hGH serum levels were 3.1+/-4.2 and 1.1+/-0.9 IU/ml in SLE and RA, respectively. PRL concentration was 18.4+/-6.5 ng/ml and 14.2+/-4.0 ng/ml in SLE and RA patients, respectively (p=0.03). In RA group, TNF-alpha was 20+/-36.2 whereas in SLE it was 4.9+/-12.8 pg/ml (p=0.03); IL-6 serum concentrations were 24.4+/-25.1 and 2.9+/-5.4 pg/ml, in RA and SLE respectively (p=0.004). The serum level of hGH showed slight increase in alexithymic group (A) compared to non alexithymic group (NA) in both SLE and RA patients. PRL serum levels in SLE-A patients was 26.7+/-17.3 ng/ml while in SLE-NA patients was 12.4+/-3.3 ng/ml (p=0.04). In RA patients increased values of IL-6 and TNF-alpha were present in the A group compared to NA group (IL-6: 35.3+/-28 pg/mL vs 3.5+/-3.9 pg/mL, p=0.01; TNF-alpha: 34.7+/-39 pg/mL vs 3.1+/-3.4 pg/mL, p=0.01). CONCLUSIONS: In this preliminary results we found an high prevalence of alexithymia and a correlation between immunoendocrine parameters and alexhytimic features in SLE and RA, suggesting that an immunomodulatory pathway could influence this cognitive style in patients with autoimmune disorders. Other studies should contribute to find a common biological pathway linking alexithymia and autoimmunity.

Pulmonary hypertension and erythropoietin.

Numerous uremic patients on hemodialysis have pulmonary hypertension attributable to the presence of arteriovenous fistulas, vascular calcification, and endothelial dysfunction due to alterations in the balance between vasoconstrictive and vasodilatory substances. For these reasons, the effects of recombinant human erythropoietin, a drug widely used in patients on dialysis, on the pulmonary circulation were studied. Some authors maintain that recombinant human erythropoietin has an antihypertensive effect, while others have observed that this hormone induces a reduction in pulmonary arterial pressure due to its vasoactive and stimulatory effects on endothelial and smooth muscle cell precursors.

Alexithymia and neuroendocrine-immune response in patients with autoimmune diseases: preliminary results on relationship between alexithymic construct and TNF-alpha levels.

Alexithymia is conceptualized as a disorder of emotion regulation mechanisms, which involves a dissociation of emotional and physical responses to life events and bodily sensations. Our results might suggest a possible relationship between the alexithymic construct and TNF levels in RA patients. These preliminary findings corroborate the integrated bidirectional interactions between neuropsychological mechanisms and the neuroendocrine-immune system in patients affected by autoimmune diseases and contribute to finding a common biological pathway linking alexithymia and autoimmune-inflammatory diseases.

The adjunctive role of antiphospholipid antibodies in systemic lupus erythematosus cardiac involvement.

OBJECTIVE: To evaluate the prevalence of cardiac alterations by trans thoracic echocardiography (TTE) and the possible role of aPLs in determining heart damage in SLE patients. PATIENTS AND METHODS: We investigated 34 consecutive Caucasian SLE patients and 34 age and sex- matched controls. All patients underwent TTE. Lupus anticoagulant (LA) was assayed. IgG and IgM antiphospholipid antibodies against cardiolipin (aCL), phosphatidylinositol (aPI), phosphatidylserine (aPS), phosphatidic acid (aPA), and anti-Beta2-glycoprotein I antibodies (aBeta2GPI) were determined by ELISA. RESULTS: Nineteen (56%) SLE patients showed at least one cardiac abnormality (P < 0.0001 - RR 19; OR 41.8; 95% CI 5.1-342). The predominant valve dysfunctions were represented by mitral (21%) and tricuspidal (18%) regurgitation. Aortic regurgitation was observed in 12% of patients, pericardial effusion and left atrial enlargement were identified in 15% and 12% of cases, respectively. Mitral valvular strands were detected in one patient. The prevalence of cardiac abnormalities correlated with disease duration. Echocardiographic alterations were more common in aPLs positive than in aPLs negative patients (P = 0.02 - RR 2.5; OR 6.1; 95% CI 1.2-30.1). Patients with IgG-aPA, -aPI and -aPS had a higher prevalence of left atrial enlargement (P < 0.05); IgG-aPA and -aPI were significantly associated with increased interventricular septum thickness (P < 0.05). CONCLUSION: Our findings confirm that the heart is one of the main target in SLE patients. The association between aPLs and cardiac impairment suggests an adjunctive role of these autoantibodies in determining heart damage. SLE vasculopathy is a multifactorial process leading to accelerated atherosclerosis. Heart involvement over the course of disease requires a comprehensive screening and management of traditional and new cardiovascular risk factors to prevent cardiac damage, which represents the primary cause of morbidity and mortality in SLE patients.

Systemic lupus erythematosus and renal involvement: which role of citokines expression?

The role of cytokines in systemic lupus erythematosus (SLE) glomerulonephritis is extremely complex. Proinflammatory molecules, such as TNF, IL-6, IL-1 and IL-18 are upregulated, as are both Thl and Th2 cytokines, with different implications: the local effects may be different from the systemic immunoregulatory ones. Excessive T helper cell function is a hallmark of SLE and abnormalities of Th citokine profiles have been implicated in loss of immune tolerance, increased antogenic load, defective B cell suppression and a variety of clinical manifestations. For some cytokines, TNF and IL-18 in particular, the local proinflammatory ones may be more relevant to the disease.

[Neuropsychiatric lupus erythematosus]. / Il lupus neuropsichiatrico.

Neuropsychiatric involvement in patients with Systemic Lupus Erythematosus (SLE), first mentioned by Kaposi more than 100 years ago, still remains one of the main challenge facing rheumatologist and other physicians. The diagnosis of neuropsychiatric SLE (NPSLE) is complex not only because of the considerable prevalence variation (14-80%) but also because of the wide spectrum of NP manifestations. They vary from overt neurologic alterations (seizure, psychosis), to subtle abnormalities (neurocognitive dysfunctions). Different NP manifestations result from a variety of mechanisms including antibodies, vasculitis, thrombosis, hemorrhages and cytokine-mediated damages. Of note, despite the dramatic clinical manifestations, too often changes at the morphological neuroimaging techniques are minimal and non specific. There is no one diagnostic tool specific for NPSLE and diagnosis must be based on the combinated use of immunoserological tests, functional and anatomical neuroimaging and standardized specific criteria. Symptomatic, immunosuppressive and anticoagulant therapies are the main strategies available in the management of these patients. Therapy for CNS lupus should be adjusted according to the needs of the individual patients. The coming years promise to be an important time for the development of new neuroimaging techniques and for the study of disease mechanism. An early and objective identification of brain involvement will allow for appropriate treatment to avoid severe complications.

The Dark Side of Blocking RAS in Diabetic Patients with Incipient or Manifested Nephropathy.

Renin-angiotensin system (RAS) inhibitors are currently advocated as the first line approach for diabetic patients with high blood pressure, particularly if early signs of renal damage are manifest. This mostly relies on the supposed benefits of these drugs, either achieved indirectly by blood pressure lowering or directly by pleiotropic effects, on cardiovascular and renal outcomes. Yet, data from large randomized controlled trials and independent meta-analyses seem to raise some concerns on the compelling use of RAS-inhibitors in the whole diabetic population as improvements in cardiovascular and renal endpoints may not be as definite as generally believed. Furthermore, the risk of adverse events, such as hyperkalemia, deserves more attention in diabetic patients.In this brief review we aimed at summarizing the most relevant available evidence on "negative" or "null" effects of RAS-inhibitors on clinical outcomes in diabetic patients, providing reasons for a "personalized" rather than generalized use of these drugs according to individual characteristics.

Stiffness parameters, intima-media thickness and early atherosclerosis in systemic lupus erythematosus patients.

Detection of early carotid vascular disease in patients with systemic lupus erythematosus (SLE) is considered mandatory for evaluation of subclinical atherosclerosis (ATS), and various ultrasonographic (US) parameters have been proposed. In the present investigation, 33 SLE and 33 healthy age-matched females have been studied by colour-coded sonography of the common carotid artery, assessing intima-media thickness (IMT), vascular strain (VS), vascular distensibility (VD), vascular stiffness (VSf) and pressure-strain elastic modulus (PSEM) as possible markers of early ATS. Patients with SLE, despite equivalent exposure to "traditional" cardiovascular risk factors, presented a higher mean IMT of the common carotid artery than healthy subjects (0.7 +/- 0.2 mm vs 0.5 +/- 0.1 mm - P < 0.0001). Of the stiffness parameters, patients with lupus showed a mean VSf of 0.72 +/- 0.38 vs 0.54 +/- 0.14 in controls (P < 0.0001) and a mean PSEM of 6.0 +/- 2.8 Pa vs 3.0 +/- 1.4 Pa in controls (P < 0.0001). Mean VS and VD were significantly lower in patients with SLE than in healthy subjects (P < 0.0001). Among individuals with IMT < 0.6 mm, patients with SLE presented more compromised stiffness parameters. IMT was shown to be a useful parameter in the evaluation of vascular damage, even in a "sub-clinical" phase, while stiffness parameters provide additional details regarding endothelial and vessel functional state. Combined evaluation may allow ATS to be detected in the early stages in patients with SLE.

[Therapy with vasopressin receptor antagonists: the aquaretics]. / La terapia con gli antagonisti della vasopressina: gli acquaretici.

Aquaretic drugs, by definition, can induce an increase in urinary volume and urinary free water associated with a decreased urinary osmolarity with a consequent increase in plasma sodium. This enhanced diuresis is not accompanied by an increased loss of electrolytes, whereas traditional diuretics have the opposite, so-called saluretic effect. Aquaretics belong to a family of vasopressin receptor antagonists, V2 in particular, that regulate tubular water reabsorption. Several studies have confirmed their utility in the treatment of hyponatremic states associated with water retention such as heart failure, cirrhosis related ascites and SIADH. Furthermore, new applications may include the treatment of arterial hypertension, polycystic kidney disease, glaucoma and Meniere's syndrome.

[A brief "update" on renal effects of caffeine]. / Rene e caffeina: un breve "update"

Caffeine is one of the most frequently consumed substances worldwide. It is present in some common beverages such as tea and coffee and in a variety of drugs, particularly analgesics. Its main mechanisms of action include inhibition of phosphodiesterase enzyme and adenosine receptors; its effects involve the whole body. In recent years there has been a debate in the scientific literature over the relationship between caffeine and the kidney and its possible toxicity. Several experimental studies have demonstrated that caffeine may exacerbate some pathological conditions such as polycystic disease and proteinuria, while others have underlined its protective effects in specific situations. While awaiting new, in-depth studies that will help to solve the debate, we can conclude that there is currently no evidence contraindicating the consumption of moderate quantities of caffeine by healthy subjects or kidney patients.

Spontaneous splenorenal shunt in a patient with antiphospholipid syndrome: the first case reported.

The antiphospholipid syndrome (APS) is an autoimmune disorder, characterized by a wide spectrum of clinical manifestations. Thromboembolic events, with a greater involvement of extremities veins, are the most common features, and obstruction of abdominal vessels are sporadically reported. We present a singular case of a patient with primary APS (PAPS) that developed a spontaneous splenorenal shunt, secondary to a total portal, mesenteric and splenic vein thrombosis. Spontaneous splenorenal shunt, an uncommon circumstance reported in cirrhotic disease, to the best of our knowledge, has not been previously described in PAPS.

Dialysis-related genotoxicity: sister chromatid exchanges and DNA lesions in T and B lymphocytes of uremic patients. Genomic damage in patients on hemodiafiltration.

BACKGROUND/AIMS: Patients with chronic renal failure show the presence of massive oxidative genome damage but the role played by dialysis is still a controversial issue. The aim of our study was to verify the genomic damage in B- and T-lymphocyte subpopulations of uremic patients after a single hemodiafiltration session. METHODS: We enrolled 30 patients on maintenance acetate-free biofiltration and 25 age-matched healthy volunteers and studied chromosomal alterations. RESULTS: Our data show that the basal levels of DNA damage, the number of sister chromatid exchanges and basal high-frequency cells levels are significantly higher in patients on hemodiafiltration than in controls and in T lymphocytes than in B cells. CONCLUSIONS: These findings suggest that hemodialytic treatment could represent a potential source of damage, maybe through the oxidative action of the extracorporeal circuit components, which might explain the well-known T-specific immunodeficiency correlated with uremia.

Intradermal skin test with diabetes specific antigens in patients with type 1 diabetes.

Cell mediated immune response in vitro to a number of antigens has been reported in patients with Type 1 diabetes. The aim of the present study was to develop an in vivo intradermal (delayed type hypersensitivity) skin test using antigens known to be recognized by lymphocytes of patients with Type 1 diabetes and to compare, where possible, the in vivo response to the in vitro T cell proliferation to the same antigens. The skin test was performed in the following group of patients: 55 with recent onset Type 1 diabetes; 16 patients with Type 1 diabetes of longer duration; 10 patients with autoimmune thyroid disease and 20 patients with Latent Autoimmune Diabetes in Adults (LADA). Type 1 diabetes specific antigens for the skin test included glutamic acid decarboxilase (GAD65), insulin and beta casein, whereas diabetes non specific antigens included tetanus toxoid, diphteria, proteus, tubercolin, streptococcus, and glycerol as control. A multitest device consisting of heads delivering intradermally 10 microl of solution containing the antigens was applied to the forearms; the specific antigens were injected in one forearm whereas the non specific antigens were injected in the other forearm. Reading of the reaction, which was considered positive in the presence of a nodule of 2 mm diameter was performed 48 h after the multitest application. The in vitro T cell response to diabetes specific antigens used in the multitest was studied using conventional proliferation assays in patients with recent onset Type 1 diabetes and in age matched normal subjects. Only recent onset Type 1 diabetes patients showed an in vivo positive response to GAD65, such response being detectable in 10 patients (18%). Two patients reacted also to beta casein and insulin, all other patient groups resulted negative but 2 patients with longer duration of Type 1 diabetes. There was no apparent link between the in vivo skin test and in vitro T cell proliferation to GAD65. We conclude that in vivo cell mediated immune reaction to GAD65, insulin and beta casein can be visualized in a minority of patients with recent onset Type 1 diabetes. Further studies are required to determine specificity and whether altering the dose can improve the sensitivity of the test.