Snapshot A 35-year-old man is brought to the emergency department for abdominal pain and flu-like symptoms for the past 2 days. He reports that he just returned from a 2-month trip throughout South America. He reports fever, fatigue, malaise, and right upper quadrant pain but denies diarrhea, melena, hematochezia, nausea, vomiting, or weight loss. A physical examination demonstrates tender hepatomegaly and mild scleral icterus. Introduction Overview condition is an acute (temporary) form of hepatitis, which describes the inflammation of the liver tissue treatment is usually supportive and dependent on the etiology Associated conditions medical conditions and comorbidities chronic hepatitis fulminant liver failure Epidemiology Risk factors alcohol abuse foreign travel intravenous drug use sexual contact ETIOLOGY Pathogenesis mechanism the specific mechanism of injury depends on the etiology generally, the initial insult results in hepatocyte injury leading to the activation of an inflammatory response, which can become chronic (with subsequent fibrosis and cirrhosis) Metabolic disease Steatohepatitis Autoimmune hepatitis Drug-induced (e.g., acetaminophen) Alcohol Parasites (e.g., toxoplasmosis) Viral hepatitides (e.g., HAV, HCV, and HBV) Presentation History recent travel sudden jaundice Symptoms common symptoms initial prodromal phase (flu-like symptoms) fatigue nausea vomiting poor appetite headaches followed by jaundice (1-2 weeks after) right upper quadrant (RUQ) pain Physical exam jaundice scleral icterus hepatomegaly splenomegaly RUQ tenderness fever Imaging Ultrasound indications good initial imaging modality for rule out of other causes of abdominal pain findings hepatomegaly (most sensitive sign) gallbladder wall thickening Studies Serum labs complete blood count (CBC) may demonstrate elevated WBC count with atypical lymphocytosis in viral hepatitis hepatic panel mixed direct and indirect hyperbilirubinemia dramatically elevated aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ALT usually higher than AST if AST:ALT > 2, suspect alcoholic hepatitis hepatitis viral serologies determines which type of virus and the immunity status IgM antibodies are present during early infection IgG antibodies are present and remain after recovery e.g., if a patient is positive for IgG but negative for IgM, the patient is immune via either prior infection or vaccination Serologic Findings Clinical Implications HBV surface antigen Anti-HBV core antibody Active infection Anti-HBV surface antigen antibody Immunity Anti-HBV core antibody Immunity HBV e-antigen C HCV antibody Exposure Differential Chronic hepatitis key distinguishing factors patient history may reveal a long period of symptoms Gallbladder disease key distinguishing factors ultrasound or other imaging modalities will demonstrate pathology or the presence of stones Treatment Lifestyle supportive care indications especially for patients with acute viral hepatitis and alcoholic hepatitis modalities fluid and electrolyte management treatment of any encephalopathy or coagulopathy monitor and management for alcohol withdrawal and abstain from alcohol nutritional support for acute alcoholic hepatitis thiamine/folate Medical antiviral therapy indications used for the treatment of severe acute hepatitis B modalities nucleoside analogues (e..g, entecavir) pentoxifylline and/or corticosteroids indications used for severe alcoholic hepatitis Complications Pancreatitis Aplastic anemia Peripheral neuropathy Myocarditis Prognosis The vast majority of patients with acute hepatitis recover completely without complications Overall, low mortality rate but prognosis may be worse if the patient has other comorbidities or initial presenting symptoms such as ascites, edema, or encephalopathy