[Pathophysiology of portal hypertension and mechanisms of sodium and water retention in cirrhosis].

Portal hypertension is caused by an increased resistance to portal outflow and an increased portal blood inflow. Portal hypertension is associated with an abnormal distribution of the blood volume, which is increased in the splanchnic territory and reduced in the non-splanchnic compartments. The relative underfilling of the arterial circulation is responsible for the sodium and water retention, which is a consequence of the baroceptor-mediated activation of vasoconstrictor and antinatriuretic factors triggered to restore circulatory integrity.

Management of hepatitis C virus-related mixed cryoglobulinemia.

Mixed cryoglobulinemia is a chronic immune complex-mediated disease strongly associated with hepatitis C virus (HCV) infection. Mixed cryoglobulinemia is a vasculitis of small and medium-sized arteries and veins, due to the deposition of complexes of antigen, cryoglobulin and complement in the vessel walls. The main clinical features of mixed cryoglobulinemia vasculitis include the triad of palpable purpura, arthralgias, and weakness, and other pathological conditions such as glomerulonephritis, peripheral neuropathy, skin ulcers, and widespread vasculitis.

[Current therapeutic strategies for HCV-associated cryoglobulinemia].

Cryoglobulinemia refers to the presence in serum of immunoglobulins, that reversibly precipitate at low temperatures. Cryoglobulins are classified according to their immunochemical properties as type I, composed of a single monoclonal immunoglobulin, and types II and III, referred as mixed cryoglobulinemia (MC), composed by a mixture of monoclonal (type II) and polyclonal (type III) IgM that have rheumatoid factor activity and bind to polyclonal IgGs. MC is a systemic vasculitis with cutaneous and multiple organ involvement including chronic hepatitis, membrano-proliferative glomerulonephritis, and peripheral neuropathy.

HLA-DRB4 as a genetic risk factor for Churg-Strauss syndrome.

Objective: To explore the association between HLA alleles and Churg-Strauss syndrome (CSS), and to investigate the potential influence of HLA alleles on the clinical spectrum of the disease.

Methods: Low-resolution genotyping of HLA-A, HLA-B, and HLA-DR loci and genotyping of TNFA -238A/G and TNFA -308A/G single-nucleotide polymorphisms were performed in 48 consecutive CSS patients and 350 healthy controls.

Results: The frequency of the HLA-DRB1*07 allele was higher in the CSS patients than in controls (27.

HCV-related cryoglobulinemic glomerulonephritis: implications of antiviral and immunosuppressive therapies.

The most frequent renal involvement in patients with chronic hepatitis C virus (HCV) infection is cryoglobulinemic glomerulonephritis, with type I membranoproliferative glomerulonephritis (MPGN) being the predominant histological pattern. The pathogenesis of HCV-related cryoglobulinemic MPGN is unknown, but the glomerular damage may be due to the deposition of immune complexes of HCV, IgG, and IgM rheumatoid factors. Clinically, cryoglobulinemic MPGN may range from isolated proteinuria to overt nephritic or nephrotic syndrome, with variable progression to chronic renal insufficiency.