Hepatocellular pattern of injury, where AST and ALT are higher than Tbili and Alk Phos; likely to have significantly elevated ALT and AST (20x normal or higher)
Of note, transmission of Hepatitis B and Hepatitis C through donated blood, blood products, and organs is rare in the US since blood screening became available in 1992
Hepatitis A
Fecal-oral transmission
Associated with epidemics linked to a common source (water)
Most common risk factor is travel outside of the US 
Not associated with chronic carrier state; incubation period is approximately 30 days, and infectivity usually resolved prior to symptom onset
Most common form of transmission occurs from asymptomatic children to adults
Approximately only 5% of infected children symptomatic
Whereas ~75% of adults are symptomatic
Incubation period: 15-50d
Prodrome: nausea/vomiting, malaise, fever, abdominal pain
1wk later: clay-colored stool, jaundice
Death from hepatic failure is rare
Fecal-oral transmission
Associated with epidemics linked to a common source (water)
Most common risk factor is travel outside of the US 
Not associated with chronic carrier state; incubation period is approximately 30 days, and infectivity usually resolved prior to symptom onset
Most common form of transmission occurs from asymptomatic children to adults
Approximately only 5% of infected children symptomatic
Whereas ~75% of adults are symptomatic
Incubation period: 15-50d
Prodrome: nausea/vomiting, malaise, fever, abdominal pain
1wk later: clay-colored stool, jaundice
Death from hepatic failure is rare
Approximately only 5% of infected children symptomatic
Whereas ~75% of adults are symptomatic
1wk later: clay-colored stool, jaundice
Hepatitis B
Transmitted parenterally, blood contact, and unprotected sex
90% of exposed infants progress to chronic hepatitis; 10% of exposed adults progress to chronic hepatitis
Serology
Incubation period: 1-3 months
Presentation is similar to hep A
Lab tests:
HBsAg: + implies infection
Anti-HBs: implies clearance or vaccination
Anti-HBc: Implies prior infection; IgM = acute & in flares; only marker in window period; IgG always present
HBe-Ag: Implies active<unk>  replication & infectivity
Anti-HBe: low infectivity
HBV DNA: Similar to HBe-Ag but more sensitive
Transmitted parenterally, blood contact, and unprotected sex
90% of exposed infants progress to chronic hepatitis; 10% of exposed adults progress to chronic hepatitis
Serology
Incubation period: 1-3 months
Presentation is similar to hep A
Lab tests:
HBsAg: + implies infection
Anti-HBs: implies clearance or vaccination
Anti-HBc: Implies prior infection; IgM = acute & in flares; only marker in window period; IgG always present
HBe-Ag: Implies active<unk>  replication & infectivity
Anti-HBe: low infectivity
HBV DNA: Similar to HBe-Ag but more sensitive
HBsAg: + implies infection
Anti-HBs: implies clearance or vaccination
Anti-HBc: Implies prior infection; IgM = acute & in flares; only marker in window period; IgG always present
HBe-Ag: Implies active<unk>  replication & infectivity
Anti-HBe: low infectivity
HBV DNA: Similar to HBe-Ag but more sensitive
Hepatitis C
Blood-borne, in US, most commonly transmitted through IV drug use. Infrequently transmitted through sexual contact
90% of HCV infections progress to chronic hepatitis
Unlike Hep A and B, most often asymptomatic in acute phase of infection
>75% of patients advance to chronic stage
Active disease identified by reactive HCV ab and positive HCV RNA
Blood-borne, in US, most commonly transmitted through IV drug use. Infrequently transmitted through sexual contact
90% of HCV infections progress to chronic hepatitis
Unlike Hep A and B, most often asymptomatic in acute phase of infection
>75% of patients advance to chronic stage
Active disease identified by reactive HCV ab and positive HCV RNA
Hepatitis D
Transmission similar to Hepatitis B
Can only co-infect patients with Hepatitis B (actively producing HBsAg)
Presentation can range from acute self-limited disease to fulminant hepatitis or chronic infection
Only occurs with comorbid hepatitis B
High incidence of cirrhosis
Transmission similar to Hepatitis B
Can only co-infect patients with Hepatitis B (actively producing HBsAg)
Presentation can range from acute self-limited disease to fulminant hepatitis or chronic infection
Only occurs with comorbid hepatitis B
High incidence of cirrhosis
Hepatitis E
Fecal-oral transmission
Usually results in mild illness, but can cause fulminant hepatitis in pregnant women
Fecal-oral transmission
No carrier state
High associated mortality
Common in Southeast Asia, but different genotypes found globally across Asia, Africa, Latin America
Mortality in pregnancy dependent on trimester
1.5% in first trimester
8.5% in second trimester
21% in third trimester
Fecal-oral transmission
Usually results in mild illness, but can cause fulminant hepatitis in pregnant women
Fecal-oral transmission
No carrier state
High associated mortality
Common in Southeast Asia, but different genotypes found globally across Asia, Africa, Latin America
Mortality in pregnancy dependent on trimester
1.5% in first trimester
8.5% in second trimester
21% in third trimester
1.5% in first trimester
8.5% in second trimester
21% in third trimester
Viral hepatitis
Acetaminophen toxicity 
Autoimmune hepatitis
Ischemic hepatitis
Hepatitis A
Hepatitis E
Hepatitis B
Hepatitis D