Liver Pathology Flashcards

1
Q

______ is a general term referring to inflammation of the liver

A

Hepatitis

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2
Q

What are causes of hepatitis?

A
  • infectious: viral, bacterial, fungal, and parasitic organisms; or
  • noninfectious: e.g., alcohol, drugs, autoimmune diseases, and metabolic diseases.
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3
Q

What can the term viral hepatitis describe?

A

either a clinical illness or the histologic findings associated with the disease

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4
Q

What specific viruses can cause viral hepatitis? (5)

A

1) hepatitis A virus (HAV)
2) hepatitis B virus (HBV)
3) hepatitis C virus (HCV)
4) hepatitis D virus (delta agent) (HDV)
5) hepatitis E virus (HEV)

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5
Q

U.S. viral hepatitis is most commonly caused by what?

A

HAV, HBV and HCV

(can all result in acute (viral) hepatitis)

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6
Q

Acute infection with HBV and HCV can lead to ______ (viral) hepatitis.
Patients who are chronically infected may go on to develop _______ and ________

A
  • chronic
  • cirrhosis
  • hepatocellular carcinoma (HCC)
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7
Q

Hepatitis A is transmitted by what?

A

a picornavirus, hepatitis A virus (HAV)

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8
Q

_____ does not cause chronic hepatitis

A

HAV

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9
Q

______ the most common cause of viral hepatitis worldwide

A

Hepatitis A

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10
Q

How is Hepatitis A transmitted?

A
  • fecal-oral route, from person to person
  • spread by ingestion of contaminated water and food
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11
Q

A major clinical finding in Hepatitis A is that _______ occurs in > 70% of patients

A

Jaundice (icterus)

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12
Q

What are serologic markers for hepatitis A?

A
  • IgM antibody against HAV appears in blood at the onset of symptoms and is a reliable marker of acute infection
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13
Q

With hepatitis A, the IgM response usually declines in a few months followed by the appearance of _____ anti-HAV that persists for years, often conferring ______ immunity

A
  • IgG
  • lifelong
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14
Q

What is Hepatitis B?

A

an acute infection of the liver parenchymal cells caused by the hepatitis B virus (HBV)

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15
Q

What are outcomes of HBV infections? (5)

A

1) acute hepatitis with recovery and clearance of the virus
2) nonprogressive chronic hepatitis
3) progressive chronic disease ending in cirrhosis
4) fulminant hepatitis with massive liver necrosis
5) an asymptomatic “healthy” carrier state (persistence of hepatitis B surface antigen).

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16
Q

HBV-induced chronic liver disease is also an important risk factor for the development of _______

A

hepatocellular carcinoma (HCC)

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17
Q

Hepatitis B is caused by HBV, a hepadnavirus, and what proteins? (3)

A
  • outer surface coat envelope glycoproteins: hepatitis B surface antigen (HBsAg)
  • inner nucleocapsid “core” protein: hepatitis B core antigen (HBcAg)
  • precore region designated: hepatitis B e antigen (HBeAg)
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18
Q

Where does HBV exist in people?

A

exists in the blood and body fluids

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19
Q

What are some ways HBV can be transmitted? (4)

A
  • parenteral route: (needles)
  • perinatal transmission
  • contact of HBV infectious material with mucous membranes and open skin breaks
  • oral intake of HBV infectious material may result in infection
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20
Q

In the US, Hepatitis B transmission is mainly ________

A

horizontal

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21
Q

What is the best predictor of chronic hepatitis B infection?

A

Patient age at the time of infection

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22
Q

Massive liver necrosis is a rare finding that may occur with Hepatitis B. When does an individual have the highest risk for this?

A

highest risk is in patients coinfected with hepatitis D

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23
Q

When does the serological marker HBsAg appear in Hepatitis B?

A

HBsAg before the onset of symptoms, peaks during symptomatic disease, and then usually declines to undetectable levels in 12 weeks

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24
Q

The detection of _____establishes infection with HBV and implies infectivity

A

HBsAg

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25
Q

______ appears after the acute disease is over and usually is not detected until a few weeks to several months after HBsAg disappears

A

Antibodies to HBsAg (Anti-HBs)

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26
Q

How long do Antibodies to HBsAg (Anti-HBs) persist in people?

A

may persist for life and confers protection

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27
Q

What do the serological markers HBeAg and HBV DNA signify in Hepatitis B?

A

signify ongoing viral replication

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28
Q

Persistence of ______ is an indicator of progression to chronic hepatitis B

A

HBeAg

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29
Q

The appearance of antibodies to HBeAg (anti-HBe) implies what?

A

an acute infection has peaked and is on the wane

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30
Q

When do IgM antibodies to HBcAg (IgM anti-HBc) become detectable in serum in Hepatitis B?

A

before the onset of symptoms, concurrent with the onset of elevated serum aminotransferase levels (indicative of hepatocyte destruction)

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31
Q

Know how to interpret hepatitis B serology results

A

see picture/chart in notes

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32
Q

What is Hepatitis C?

A

an acute liver parenchymal infection caused by hepatitis C virus (HCV)

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33
Q

In Hepatitis C, there are at least _____ major genotypes.
What are most common in USA?

A
  • 6
  • 1a and 1b are the most common in the U.S.
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34
Q

Most HCV transmission is ______

_______ accounts for most HCV transmission in the U.S

A
  • parenteral
  • Injecting-drug use
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35
Q

HCV infection may stimulate production of what?

A

cytotoxic T-lymphocytes and cytokines (INF-gamma), which probably mediate hepatic necrosis

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36
Q

When do symptoms of Hepatitis C develop?

A

develop 7 to 8 weeks after infection (range of 2 to 26 weeks), but 70% to 80% of cases are subclinical

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37
Q

What happens to ~ 10 - 20% of patients after acute hepatitis C infection?

A

they clear the HCV infection and have complete resolution

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38
Q

Progression to chronic HCV infection is ______ and occurs in ~______% of patients

A
  • common
  • 80 - 90
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39
Q

chronic HCV infection, ________ may develop and include a variety of immunologic and lymphoproliferative disorders

A

extrahepatic manifestations / sequelae

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40
Q

15 - 20% of those patients with chronic HCV will develop _______ over a period of 20 to 30 years;

A

cirrhosis

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41
Q

The serological marker _______ is detectable in blood for 1 to 3 weeks and is coincident with elevations in serum transaminases in hepatitis C

A

HCV RNA

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42
Q

In symptomatic acute HCV infection, _____ are detected in only 50 - 70% of patients;

A

anti-HCV antibodies

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43
Q

In chronic HCV infection, circulating _____ persists in ~ 90% of patients despite the presence of neutralizing antibodies

A

HCV RNA

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44
Q

Why must testing for HCV RNA be done in hepatitis C?

A

must be done to confirm the diagnosis of chronic HCV infection

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45
Q

What is a characteristic clinical feature of chronic HCV infection

A

episodic elevations in serum aminotransferases

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46
Q

What is Hepatitis D virus also called

A

delta agent

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47
Q

What is Hepatitis D Virus dependent on for its life cycle?

A

dependent for its life cycle on HBV

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48
Q

Coinfection with _______ is associated with higher rates of severe acute hepatitis and fulminant liver failure

A

HBV and HDV

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49
Q

How is Hepatitis E Virus (HEV) most commonly transmitted?

A

by the fecal-oral (water-borne infection) route

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50
Q

A characteristic feature of HEV infection is what?

A

high mortality rate among pregnant women, approaching 20%

51
Q

What is Autoimmune hepatitis (AIH)

A

an immune-mediated, inflammatory liver disease characterized by elevated serum globulin levels (IgG), circulating characteristic autoantibodies, and the typical histology of interface hepatitis, plasma cell rich infiltration, and lobular hepatitis

52
Q

In Autoimmune hepatitis (AIH), _____ develops in at least 40% of survivors

A

cirrhosis

53
Q

What are histologic/morphologic features of autoimmune hepatitis? (3)

A
  • necrosis and inflammation
  • plasma cell predominance
  • Hepatocyte “rosettes”
54
Q

What is cirrhosis also called?

A

End-stage liver disease

55
Q

What is cirrhosis the end result of?

A

irreversible hepatocellular injury that is characterized by diffuse transformation of the entire liver into regenerative parenchymal nodules surrounded by fibrous bands.

56
Q

What is the pathological hallmark of cirrhosis?

A

development of fibrous scar tissue that replaces normal hepatic parenchyma, leading to blockade of hepatic portal blood flow and disturbance of normal liver function

57
Q

What do the clinical features of cirrhosis result from? (3)

A
  • hepatic cell (hepatocyte) dysfunction (hepatic insufficiency)
  • portosystemic shunting
  • portal hypertension
58
Q

What are common causes of cirrhosis in the US? (6)

A
  • Hepatitis C: 26%
  • Alcoholic liver disease: 21%
  • Hepatitis C with concurrent alcoholic liver disease: 15%
  • Cryptogenic (unknown) causes: 18% (due to nonalcoholic fatty liver disease [NAFLD])
  • Hepatitis B (including coincident hepatitis D): 15%
  • Miscellaneous: 5%
59
Q

Up to 40% of patients with cirrhosis have _______ and demonstrate no clinical symptoms

A
  • compensated cirrhosis
60
Q

What clinical presentation do patients with decompensated cirrhosis have? (3)

A
  • symptomatic complications related to cirrhosis
  • hepatic insufficiency (e.g., jaundice or hepatic encephalopathy)
  • portal hypertension (e.g., ascites or esophageal variceal hemorrhage
61
Q

What are signs and symptoms of Cirrhosis involving the skin and eyes? (6)

A
  • Jaundice (icterus) and scleral icterus
  • Ecchymosis
  • Palmar erythema
  • Spider angiomas
  • Spider angiomas
  • Pruritus
62
Q

How does cirrhosis affect the liver?

A

Hepatomegaly:
- the liver is enlarged, palpable, and firm
- Tender hepatomegaly and abdominal pain

63
Q

How does cirrhosis affect the spleen?

A

-Splenomegaly / hypersplenism
- portal hypertension and hepatic congestion

64
Q

Abdominal _____ develops in ~ 60% of patients with cirrhosis, and peripheral _____ is manifested by clubbing of the distal phalanges of the fingers

A
  • ascites
  • edema
65
Q

What are some general signs of cirrhosis?

A
  • Weakness, fatigability, muscle cramps, and weight loss
  • Anorexia
  • Fetor hepaticus (a characteristic body and breath odor)
66
Q

What are oral findings of cirrhosis?

A
  • Hemorrhagic changes
  • Impaired gustatory function
  • glossitis
  • loss of tongue papillae
  • angular or labial cheilitis
  • candidal infection
  • bilateral, painless hypertrophy of the parotid glands (sialadenosis)
67
Q

What are common elevated laboratory findings in cirrhosis? (7)

A
  • Elevated aminotransferases (aspartate & alanine aminotransferase)
  • Plasma conjugated bilirubin
  • Serum ammonia
  • Serum lactate dehydrogenase (LDH)
  • Serum alpha-fetoprotein (AFP)
  • Serum alkaline phosphatase
  • Alpha-2-macroglobulin (A2M)
68
Q

What are common decreased laboratory findings in cirrhosis?

A
  • Serum albumin
  • Platelet count (Thrombocytopenia)
  • Depletion of vitamin K
69
Q

_____ is fairly common in cirrhosis and usually normocytic - normochromic

A

Anemia

70
Q

In cirrhosis, reduced ______ synthesis and deficiencies of vitamin K-dependent coagulation factors II (prothrombin) V, VII, IX, and X can result in abnormally elevated _______ and INR and impaired _____ and risk for increased bleeding

A
  • hepatic
  • prothrombin time (PT)
  • hemostasis
71
Q

In cirrhosis, reduced hepatic synthesis of fibrinogen leads to what?

A

hypofibrinogenemia and dysfibrinogenemia

72
Q

A common symptom of cirrhosis is hepatic failure. What are 3 complications directed associated with this?

A
  1. Hepatic encephalopathy
  2. Hepatorenal syndrome
  3. Hepatopulmonary syndrome
73
Q

What are some common complications of cirrhosis?

A
  • Portal hypertension
  • Esophageal varices
  • Upper gastrointestinal (GI) tract bleeding
  • Hepatocellular carcinoma
  • Increased risk of systemic infection
  • Cardiomyopathy
74
Q

What can portal hypertension from cirrhosis lead to?

A
  • a large increase in blood flow resistance through the liver (i.e., chronic passive congestion
  • increased portal venous inflow and increased resistance to portal blood flow.
75
Q

What are esophageal varices the direct result of?

A

increased blood pressure due to portal hypertension

76
Q

Upper gastrointestinal (GI) tract bleeding may occur from what?

A

esophageal varices, portal hypertensive gastropathy, or gastroduodenal ulcer

77
Q

What is the most common fatal complication of cirrhosis?

A

variceal rupture

(Hemorrhage from ruptured esophageal varices may be massive, resulting in fatal exsanguination)

78
Q

Up to 5% of patients with cirrhosis are at risk to develop _______ annually

A

hepatocellular carcinoma

79
Q

What systemic infection does cirrhosis increase the risk of?

A

spontaneous bacterial peritonitis

80
Q

What is Primary Biliary Cholangitis (also called Primary Biliary Cirrhosis) (PBC)

A

a chronic, variably progressive cholestatic liver disease manifested by fatigue and pruritus

81
Q

Who is most commonly diagnosed with primary biliary cholangitis (PBC)

A

PBC has a female-to-male ratio of 9:1

82
Q

What is primary biliary cholangitis (PBC) characterized by?

A

autoimmune destruction of intralobular bile ducts leading to portal inflammation, hepatic cell necrosis, fibrosis, and, if left untreated, cirrhosis, liver failure, and death

83
Q

What is the etiology of primary biliary cholangitis (PBC)

A

believed to require both a genetic susceptibility as well as an environmental trigger → persistent T-lymphocyte–mediated attack on intrahepatic bile duct epithelial cells

84
Q

Patients with PBC have a ten-fold increased concentration of PDC-E2-specific _______

A

cytotoxic CD8+ lymphocytes

85
Q

What are the serologic hallmark of PBC?

A

antimitochondrial antibodies (AMAs)

86
Q

In primary biliary cholangitis (PBC), autoimmune damage to _____ results in bile leaking into liver parenchyma resulting in hepatocyte _______, which can lead to progressive fibrosis and eventual _______

A
  • bile ducts
  • necrosis
  • cirrhosis
87
Q

What are the usual presenting symptoms of primary biliary cholangitis (PBC)

A

Fatigue (50 - 78% of patients) and pruritus (20 -70% of patients)

88
Q

In primary biliary cholangitis (PBC), _______ is present predominantly on the palm and soles, is worse at night and with constricting garments, and is worse with dry skin and humid weather

A

Pruritus

89
Q

Besides fatigue and pruritus, what are other symptoms of primary biliary cholangitis (PBC)? (5)

A
  • Jaundice
  • portal hypertension
  • hyperlipidemia,
  • osteoporosis
  • Kayser-Fleischer rings
90
Q

What autoimmune diseases may primary biliary cholangitis (PBC) be associated with? (3)

A
  • Sjögren’s syndrome
  • rheumatoid arthritis
  • systemic lupus erythematosus
91
Q

What is another name for fatty liver disease?

A

steatosis

92
Q

What is fatty liver disease (steatosis)?

A

accumulation of triglycerides and other lipids within the liver cells (hepatocytes)

93
Q

What is fatty liver disease (steatosis) mainly comprised of?

A

Alcoholic Liver Disease (ALD) and Non-alcoholic Fatty Liver Disease (NAFLD)

94
Q

Alcoholic Liver Disease (ADL) 3 morphologic / histologic states associated with alcoholic liver disease. What are they?

A
  • alcoholic steatosis (fatty liver)
  • alcoholic hepatitis
  • alcoholic cirrhosis
95
Q

Is Alcoholic Fatty Liver (or Alcoholic Steatosis) permanent or reversible?

A

reversible with abstinence from alcohol use or may progress to alcoholic hepatitis with continued alcohol use

96
Q

During Alcoholic Fatty Liver (or Alcoholic Steatosis), ______ accumulates in the liver parenchyma (hepatocytes).
_____ accumulation spreads outward from the central vein to hepatocytes in the mid-lobule and then the _____ regions

A
  • fat
  • lipid
  • periportal
97
Q

How would you describe fatty livers with widespread steatosis macroscopically?

A

enlarged, soft, yellow, and greasy

98
Q

What takes place during Alcoholic Hepatitis?

A

Inflammation and swelling of hepatocytes

99
Q

During Alcoholic Hepatitis, hepatocytes undergo swelling (ballooning) and _____; these features are most prominent in the _____ regions

A
  • necrosis
  • centrilobular
100
Q

During Alcoholic Hepatitis, predominantly _____ infiltration may permeate the lobule and accumulate around degenerating ______

A
  • neutrophilic
  • hepatocytes
101
Q

What do more severe cases of alcoholic hepatitis lead to?

A

cirrhosis and liver failure

102
Q

In Alcoholic Cirrhosis, Liver damage is usually considered _____ with regenerative, hyperplastic nodules and progressive hepatic _____

A
  • irreversible
  • fibrosis
103
Q

In Alcoholic Cirrhosis, fibrosis appears first in the _________ region as central vein sclerosis. _______ appears next in the space of Disse.

A
  • centrilobular
  • Perisinusoidal scarring
104
Q

In Alcoholic Liver Disease (ADL), alcohol metabolism is shifted to the production of NADH. This leads to what?

A
  • glycerol phosphate, which combines with the fatty acids and becomes triglycerides, which accumulate within the liver.
105
Q

In Alcoholic Liver Disease (ADL), when lipid _____ (lipolysis) stops due to alcohol consumption, fats accumulate in the liver and leads to (alcoholic) ______

A
  • oxidation
  • fatty liver disease
106
Q

In Alcoholic Liver Disease (ADL), interleukins with the help of _____ attack the hepatocytes, leading to swelling and ______ of the hepatocytes that is associated with ______ hepatitis

A
  • neutrophils
  • inflammation
  • alcoholic
107
Q

What is Non-alcoholic fatty liver disease (NAFLD)?

A
  • a spectrum of diseases based on histopathologic findings
  • liver disease occurring in patients who do not abuse alcohol and manifesting histologically by mononuclear cells and/or neutrophils, hepatocyte ballooning, and spotty necrosis
108
Q

What are two subsets of Non-alcoholic fatty liver disease (NAFLD)?

A
  • Non-alcoholic steatohepatitis (NASH)
  • Non-alcoholic fatty liver (NAFL)
109
Q

In Non-alcoholic steatohepatitis (NASH), patients have progressive disease that can result in ______ and _____. It is characterized by steatosis, lobular inflammation, and hepatocellular (hepatocyte) _____ seen on liver biopsy

A
  • fibrosis
  • cirrhosis
  • ballooning
110
Q

Non-alcoholic fatty liver (NAFL) is also known as what?

A

“isolated fatty liver”

111
Q

What is Non-alcoholic fatty liver (NAFL) characterized by?

A

harmless, reversible, non-progressive steatosis and hepatomegaly

112
Q

NAFL typically does not cause _____ inflammation, fibrosis or hepatocyte ballooning; or cause liver damage, and will almost never progress to ______ .

A
  • liver
  • cirrhosis
113
Q

What are the main risk factors for Non-alcoholic fatty liver (NAFL)

A
  • obesity
  • diabetes mellitus
  • hypertension

(metabolic syndrome)

114
Q

_____ and _____ resistance are the most reproducible etiologic factors in the development of NAFLD, and appear to be the two key initiating events for the development of NAFLD

A
  • Obesity
  • insulin
115
Q

What does the development of obesity and insulin resistance in NAFLD increase?

A

increase the mobilization of free fatty acids from adipose tissue, which are taken up by hepatocytes, and to stimulate the synthesis of fatty acids within hepatocytes

116
Q

Excessive ______ lipids and their metabolic intermediates _____ insulin resistance in the liver and _____ hepatocytes to the toxic effects of inflammatory cytokines

A
  • intrahepatic
  • enhance
  • sensitize
117
Q

Hepatocytes in patients with NASH show evidence of ______ activation

A

inflammasome

118
Q

Liver injury resulting from NAFLD mechanisms causes _______ activation, ______ deposition, and hepatic fibrosis, which along with ongoing hepatocyte _____

A
  • stellate (Ito) cell
  • collagen
  • damage
119
Q

What are complications of Non-alcoholic Fatty Liver Disease (NAFLD)? (3)

A
  • Cardiovascular disease
  • Cirrhosis
  • Hepatocellular carcinoma (HCC)
120
Q

Patients with NAFLD/NASH have an increased risk for what cardiovascular diseases?

A
  • coronary artery disease
  • left ventricular hypertrophy
  • atrial fibrillation
  • cerebrovascular disease [stroke]
121
Q

What is Hepatocellular Carcinoma (HCC)

A

(also known as hepatoma) is a primary malignant tumor of the liver

122
Q

What are the main risk factors for Hepatocellular Carcinoma (HCC)

A

Chronic HBV infection, chronic HCV infection, alcoholic liver disease, non-alcoholic steatohepatitis (NASH) and cirrhosis

123
Q

What are secondary risk factors for Hepatocellular Carcinoma (HCC)

A
  • Primary biliary cholangitis, hemochromatosis, alpha-1-antitrypsin deficiency, and autoimmune hepatitis.
  • History of excessive alcohol ingestion
  • Aflatoxin B1 (a mycotoxin)
124
Q

Cirrhotic-related HCC patients may present with symptoms of new-onset decompensated ______ and liver failure with _____ being the commonest presentation for HCC

A
  • cirrhosis
  • abdominal pain