Microscopic anatomy of liver disease Flashcards
What is steatosis?
Steatosis refers to the accumulation of triglycerides in the cytoplasm of hepatocytes.
Is steatosis a specific diagnosis?
No, steatosis is a non-specific finding and can be seen in various conditions.
What are the two morphologic patterns of steatosis?
The two morphologic patterns of steatosis are macrovesicular and microvesicular steatosis.
What are some causes of macrovesicular steatosis?
Macrovesicular steatosis can be caused by alcohol consumption, diabetes, obesity, cachexia, protein-energy malnutrition, and the use of certain drugs like corticosteroids or methotrexate.
What are some causes of microvesicular steatosis?
Microvesicular steatosis can be seen in conditions such as acute fatty liver of pregnancy, Reye syndrome, and as a side effect of drugs like valproate (used to treat epilepsy and bipolar disorder) and tetracycline (an antibiotic with protein inhibition activity).
Which type of steatosis, macrovesicular or microvesicular, is more common?
Macrovesicular steatosis, characterized by a single large vacuole distending the hepatocyte, is more common.
Is macrovesicular steatosis considered a benign and reversible lesion?
Yes, if uncomplicated, macrovesicular steatosis is regarded as a benign and potentially fully reversible lesion.
What distinguishes microvesicular steatosis from macrovesicular steatosis?
Microvesicular steatosis is characterized by many tiny droplets of fat within hepatocytes, which can be difficult to identify. It is generally a serious lesion associated with impaired lipid oxidation, disturbed liver function, and coma.
What is the definition of steatohepatitis?
Steatohepatitis refers to the combination of fatty liver change (steatosis) and inflammation (hepatitis).
What are the two most common types of steatohepatitis?
The two most common types of steatohepatitis are alcoholic steatohepatitis (ASH) and non-alcoholic steatohepatitis (NASH).
What are the characteristic features of alcoholic steatohepatitis?
Alcoholic steatohepatitis is characterized by macrovesicular steatosis (accumulation of large fat droplets), ballooned hepatocytes, Mallory-Denk bodies (abnormal protein aggregates), an inflammatory reaction mainly consisting of neutrophils, and pericellular (chicken-wire) fibrosis.
What does the trichrome stain show in alcoholic steatohepatitis?
The trichrome stain highlights the accumulation of perisinusoidal scar tissue, which spreads outward and encircles individual or small clusters of hepatocytes, creating a chicken wire fence-like pattern.
What are the key features of alcoholic steatohepatitis?
Alcoholic steatohepatitis is characterized by fatty change (steatosis), ballooned hepatocytes, and the presence of hyaline/Mallory-Denk bodies.
What are the stages of alcoholic liver disease?
Alcoholic liver disease can progress through stages including steatosis, alcoholic hepatitis, progressive steatofibrosis (accumulation of fat and fibrosis), and eventual cirrhosis.
What is considered the threshold for the development of alcoholic liver disease?
Consumption of 60-80 grams of alcohol per day for several decades is considered the threshold for the development of alcoholic liver disease.
What is the recommended alcohol consumption limit according to the NHS (National Health Service)?
The NHS recommends no more than 14 units of alcohol per week, spread over 3 or more days. One unit is equivalent to 8 grams of alcohol.
How long does it typically take for cirrhosis to develop in chronic alcoholics?
It may take 10 to 15 years of drinking for the development of cirrhosis, which occurs only in a small proportion of chronic alcoholics.
What are some of the pathologic effects of alcohol on the liver?
The pathologic effects of alcohol on the liver include changes in lipid metabolism, decreased export of lipoproteins, and cell injury caused by reactive oxygen species and cytokines.
What is cirrhosis?
Cirrhosis is the end result of continued damage to hepatocytes from various causes. It is characterized by the disruption of liver architecture, the formation of regenerating hepatocyte nodules separated by fibrous bands.
What factors contribute to the development of cirrhosis?
Cirrhosis is the result of ongoing inflammation, parenchymal damage, fibrogenesis, fibrolysis, and hepatocellular regeneration, similar to the wound healing response.
What are the consequences of progressive scarring in cirrhosis?
Progressive scarring leads to altered organ structure, altered organ function, and can ultimately result in liver failure.
How can the possible cause of cirrhosis be determined?
In cases of cirrhosis, it is important to look for pointers or clues that may suggest the underlying cause, as various factors such as alcohol consumption, viral hepatitis, autoimmune conditions, and metabolic disorders can contribute to its development.
How was cirrhosis historically classified based on nodular size?
Historically, cirrhosis was classified into macronodular (>3mm) and micronodular (<3mm) types based on the size of the nodules.
Can cirrhosis be reversible?
While certain variables may allow for some reversibility in cirrhosis, complete reversibility is rare.
What are some differential diagnoses for cirrhosis?
Cirrhosis must be distinguished from other nodular and fibrotic conditions of the liver. The differential diagnosis includes nodular regenerative hyperplasia (diffuse nodules of hyperplastic hepatocytes with minimal fibrosis), congenital hepatic fibrosis (progressive fibrosis without nodular regeneration), and focal nodular hyperplasia (a focal lesion rather than a diffuse process seen in cirrhosis).
What special stains can be used in the evaluation of cirrhosis?
Reticulin stain and Van Gieson stain are commonly used special stains in the evaluation of cirrhosis.
