5.19
Cirrosi I: Introduzione
La cirrosi è una malattia epatica cronica e irreversibile caratterizzata dalla sostituzione diffusa del tessuto epatico sano con tessuto cicatriziale…
La cirrosi si sviluppa quando una lesione cronica del fegato provoca la presenza di tessuto cicatriziale e noduli che sostituiscono tessuto epatico sano. Questo distorce la struttura del fegato e ne compromette la funzione.
Questo danno progressivo può derivare da varie cause, tra cui l'uso cronico di alcol, infezioni da epatite B e C e fegato adiposo non alcolico.
Inoltre, le malattie autoimmuni del fegato, come l'epatite autoimmune, e i disturbi metabolici ereditari, come la malattia di Wilson, possono contribuire alla cirrosi.
Con il progredire della malattia, si formano noduli rigenerativi, racchiusi da bande fibrose, causando cambiamenti strutturali che morfologicamente si suddividono in tre tipi:
La cirrosi micronodulare è caratterizzata da piccoli noduli uniformi tipicamente inferiori a 3 millimetri di diametro.
La cirrosi macronodulare è definita da noduli più grandi e di forma irregolare separati da bande prominenti di tessuto fibroso.
Nella cirrosi mista, una combinazione di noduli piccoli e grandi provoca una superficie epatica irregolare e irregolare.
Queste alterazioni strutturali portano a una funzione epatica compromessa e a un aumento della pressione portale.
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Q1: What causes cirrhosis to develop?
Cirrhosis develops from chronic liver injury that triggers progressive fibrosis and structural remodeling. Common causes include chronic alcohol use, hepatitis B and C infections, and nonalcoholic fatty liver disease. Other causes encompass autoimmune liver diseases like autoimmune hepatitis, inherited metabolic disorders such as Wilson disease, and prolonged exposure to hepatotoxic substances.
Q2: How does cirrhosis affect liver structure and function?
Cirrhosis replaces healthy liver tissue with fibrotic scar tissue and regenerative nodules, distorting the liver's normal architecture. These structural alterations lead to compromised liver function and increased portal pressure. The progressive damage impairs the liver's ability to perform its vital metabolic, synthetic, and detoxification roles.
Q3: What are the three morphological types of cirrhosis?
Micronodular cirrhosis features small, uniform nodules less than 3 millimeters in diameter, typically associated with alcoholic liver disease. Macronodular cirrhosis displays larger, irregularly shaped nodules separated by prominent fibrous bands, often linked to chronic hepatitis infections. Mixed cirrhosis combines both small and large nodules, reflecting advanced or evolving liver pathology.
Q4: What general symptoms do cirrhosis patients experience?
Cirrhosis presents with general symptoms including fatigue, loss of appetite, and weight loss. These occur alongside gastrointestinal symptoms such as nausea, vomiting, tender hepatomegaly, and jaundice. The combination of these symptoms reflects the progressive decline in liver function and metabolic capacity.
Q5: What extrahepatic signs indicate advanced cirrhosis?
Advanced cirrhosis produces extrahepatic signs including palmar erythema, spider angiomas, and muscle wasting. Men may develop gynecomastia and testicular atrophy, while women experience menstrual irregularities. Enlargement of the parotid and lacrimal glands also occurs, reflecting systemic effects of hepatic dysfunction and portal hypertension.
Q6: How do autoimmune and metabolic disorders contribute to cirrhosis?
Autoimmune liver diseases like autoimmune hepatitis trigger chronic inflammation and hepatocyte loss, activating fibrogenic pathways that lead to cirrhosis. Inherited metabolic disorders such as hemochromatosis, Wilson disease, and alpha-1 antitrypsin deficiency cause progressive liver damage through abnormal accumulation or deficiency of essential proteins, ultimately resulting in cirrhosis.
Q7: What role does chronic inflammation play in cirrhosis development?
Chronic inflammation from sustained liver injury activates fibrogenic pathways, leading to hepatocyte loss and progressive fibrosis. Regardless of the underlying cause—whether viral hepatitis, alcohol, or metabolic dysfunction—all pathways converge on chronic inflammation as the central mechanism driving scar tissue formation and cirrhosis ii pathophysiology.