A 53-year-old man complains of acute onset of vomiting during a Caribbean cruise. He has had multiple episodes of vomiting since the morning and feels "dehydrated." The patient also reports an episode of watery diarrhea, mild headache, and muscle pains. His temperature is 38.1 C (100.6 F) and the remainder of the physical examination is unremarkable. He traveled to Mexico for business a month ago. Ten other passengers on the cruise report similar symptoms. Stool cultures are negative. Which of the following is the most likely cause of this patient's condition?

Question

A 53-year-old man complains of acute onset of vomiting during a Caribbean cruise.  He has had multiple episodes of vomiting since the morning and feels "dehydrated."  The patient also reports an episode of watery diarrhea, mild headache, and muscle pains.  His temperature is 38.1 C (100.6 F) and the remainder of the physical examination is unremarkable. He traveled to Mexico for business a month ago.  Ten other passengers on the cruise report similar symptoms.  Stool cultures are negative.  Which of the following is the most likely cause of this patient's condition?

Quizplus · Accepted Answer

Explanation: 11ec2b69_c16a_dfd1_8f63_d1b4b73abaf1_MD0005_00 This patient presents with vomiting-predominant gastroenteritis and negative stool culture, which are suggestive of norovirus. Norovirus is the most common cause of epidemic gastroenteritis and is now the most common cause of all gastroenteritis in adults and children. Norovirus is spread via fecal-oral contamination, and the virus can be transmitted from food and water, fomites, or airborne droplets from vomitus. Norovirus outbreaks are common and occur in institutionalized settings such as nursing homes and health care facilities, in addition to restaurants and cruise ships. Norovirus can cause the following: Asymptomatic infection Fever with watery diarrhea - noninflammatory small-bowel process Severe illness - fever, vomiting, headache, and other systemic symptoms Symptoms usually start suddenly and last 48-72 hours. Diagnosis is generally clinical, and most patients improve with supportive care. If needed, diagnosis can be confirmed by polymerase chain reaction or nucleic acid-based testing. (Choice A) Campylobacter infection most commonly presents with acute onset of cramping abdominal pain and inflammatory diarrhea (eg, mucus, blood). Diagnosis is by stool culture. (Choice B) Clostridium perfringens is typically associated with traumatic gas gangrene but is also an important cause of watery diarrhea. The spores of C perfringens germinate in warm food; once ingested, the bacteria produce a toxin in the gastrointestinal tract that causes disease. Fever and vomiting are uncommon. (Choice C) Enterotoxigenic Escherichia coli is the most common causative agent of travelers' diarrhea, but is much less frequently a cause of diarrhea in outbreaks. It classically presents with malaise, anorexia, and abdominal cramps, followed by the acute onset of watery diarrhea. (Choice D) Listeria monocytogenes is a rare cause of epidemic gastroenteritis (usually associated with deli meats and soft cheeses). In addition to watery diarrhea, fever, and nausea/vomiting, L monocytogenes gastroenteritis may also present with non-gastrointestinal symptoms such as myalgia, arthralgia, and headache. Diagnosis can be confirmed from special stool culture media. Educational objective: Norovirus is the most common cause of gastroenteritis, including epidemic gastroenteritis, in adults and children. Vomiting is more prominent. Outbreaks are common and occur in restaurant, travel, and health care settings. References: Norovirus gastroenteritis. (http://www.ncbi.nlm.nih.gov/pubmed/19864676) Acute gastroenteritis surveillance through the National Outbreak Reporting System, United States. (http://www.ncbi.nlm.nih.gov/pubmed/23876187)

A 53-Year-Old Man Complains of Acute Onset of Vomiting During