A 32-year-old man comes to the office due to fever, jaundice, vomiting, and decreased appetite for the past 5 days. He recently returned home from South America and reports that a couple of his travel companions have had similar symptoms. The patient does not use alcohol, tobacco, or illicit drugs and has no relevant family history. Temperature is 38.8 C (101.8 F), blood pressure is 125/80 mm Hg, pulse is 85/min. Scleral icterus and hepatomegaly are present. Laboratory results are as follows: Which of the following pathophysiologic events is most likely occurring in this patient?

Question

A 32-year-old man comes to the office due to fever, jaundice, vomiting, and decreased appetite for the past 5 days.  He recently returned home from South America and reports that a couple of his travel companions have had similar symptoms.  The patient does not use alcohol, tobacco, or illicit drugs and has no relevant family history.  Temperature is 38.8 C (101.8 F), blood pressure is 125/80 mm Hg, pulse is 85/min.  Scleral icterus and hepatomegaly are present.  Laboratory results are as follows:  Which of the following pathophysiologic events is most likely occurring in this patient?

Quizplus · Accepted Answer

11ec160b_394c_ab69_9249_ab9c359206c7_MD0001_00 This patient has hepatitis A, a fecal-orally transmitted virus often linked to undercooked shellfish and unsanitary water supplies. Individuals at increased risk include those traveling to endemic areas (eg, South America), homeless shelter residents, and men who have sex with men. Typical manifestations include fever, jaundice, hepatomegaly, and leukocytosis. Liver aminotransferase levels (eg, alanine aminotransferase [ALT], aspartate aminotransferase [AST]) are dramatically elevated with levels often >1,000 U/L. Hepatitis A triggers a robust CD8⁺ lymphocytic and natural killer cell response to clear infected hepatocytes; the resulting hepatocellular damage is self-limited, with complete resolution within 2-3 months. Biopsy is not usually necessary for diagnosis, but typically shows a mononuclear periportal infiltrate; ballooning degeneration of hepatocytes and focal necrosis are also sometimes seen in the periportal parenchyma. (Choice A) Alpha-1 antitrypsin (AAT) deficiency causes liver disease characterized by intracytoplasmic accumulation of a misfolded and abnormally polymerized AAT protein. However, the onset of symptoms is chronic, fever is not present, and aminotransferase elevations are generally <1,000 U/L. Also, pulmonary symptoms (eg, dyspnea, cough) are common because AAT deficiency also causes early-onset emphysema. (Choice C) Histologic findings in alcohol-induced liver disease include lobular neutrophilic infiltrates, steatosis, ballooning of hepatocytes, and formation of Mallory-Denk bodies (eg, cytoplasmic eosinophilic inclusions within hepatocytes). However, aminotransferase elevations are modest and rarely exceed 300 U/L, usually with an AST/ALT ratio >2:1, which is not present in this patient. (Choice D) Lymphoplasmacytic infiltration is characteristic of autoimmune hepatitis. However, multiple people would not be affected with similar symptoms (as in this case) and fever is uncommon. (Choice E) Chronic hepatic injury due to a variety of causes is associated with stellate cell activation and transformation into collagen-producing myofibroblasts, leading to hepatic fibrosis and cirrhosis. However, although acute hepatic injury in hepatitis A infection may be severe, chronic infection with progression to cirrhosis is rare. Educational objective: Hepatitis A presents with fever, jaundice, hepatomegaly, leukocytosis, and aminotransferase levels >1,000 U/L. It triggers a robust CD8⁺ lymphocytic response to clear infected hepatocytes. The resulting hepatocellular damage is self-limited, with complete resolution within 2-3 months.

A 32-Year-Old Man Comes to the Office Due to Fever