Please confirm topic selection

Are you sure you want to trigger topic in your Anconeus AI algorithm?

Please confirm action

You are done for today with this topic.

Would you like to start learning session with this topic items scheduled for future?

Updated: Feb 22 2020

Norovirus

Images
https://upload.medbullets.com/topic/121540/images/norovirus.jpg
  • Snapshot
    • A 25-year-old man presents to his primary care physician for vomiting and diarrhea. He reports that he recently went on a 3-day cruise to the Caribbean. Two days after returning home, he started feeling nauseous and has had 3 episodes of nonbloody, nonbilious vomiting and watery diarrhea. He has been trying to drink fluids but has not been successful due to nausea. On physical exam, his mucous membranes are dry and his abdomen is soft and nontender to palpation. He is given a liter of normal saline and stool studies are sent.
  • Introduction
    • Classification
      • norovirus
        • a non-enveloped, linear, single-stranded, positive-sense RNA virus with an icosahedral capsid
        • a calicivirus
        • formerly known as “Norwalk” virus
        • causes gastroenteritis
        • transmission via direct contact or fecal-oral
    • Epidemiology
      • incidence
        • most common cause of nonbacterial gastroenteritis
        • more common in winter
      • demographics
        • all ages
      • risk factors
        • close living quarters
          • dorms
          • military ships
          • cruise ships
    • Pathogenesis
      • the virus is highly contagious
      • the virus causes damage to small intestine microvilli
      • enzymatic dysfunction at the brush border causes diarrhea
      • the virus also causes delayed gastric emptying and motility dysfunction, resulting in vomiting
    • Prognosis
      • symptoms occur 1-2 days after exposure to virus
      • typically self-limited
  • Presentation
    • Symptoms
      • nausea
      • vomiting
      • watery diarrhea
      • headaches
      • myalgia
    • Physical exam
      • abdominal exam
        • may have diffuse tenderness or none
  • Studies
    • Labs
      • detection of serum antibodies (IgM) to norovirus
      • stool studies
        • no fecal leukocytes
        • no occult blood
        • stool culture to exclude other agents
    • Making the diagnosis
      • most cases are clinically diagnosed
  • Differential
    • Salmonella gastroenteritis
      • distinguishing factor
        • typically has fecal leukocytes and occult blood on stool studies
  • Treatment
    • Management approach
      • the mainstay of treatment is supportive care
    • Conservative
      • supportive care
        • indication
          • all patients
        • modalities
          • intravenous hydration
          • electrolyte repletion
          • anti-emetics
          • analgesics
  • Complications
    • Dehydration
Card
1 of 0
Question
1 of 2
Private Note