Diagnosing and Treating Influenza in the Emergency Department: An Evidence- Based Update (Infectious Disease CME, Pharmacology CME, Risk Management CME)

An 81-year-old man with a past medical history of congestive heart failure and Alzheimer disease presents with 3 days of fever, dry cough, confusion, and decreased oral intake…

• He is a resident of a long-term care facility. The caretaker accompanying him reports that multiple residents of the facility have been ill with similar symptoms this week.
• His vital signs are temperature, 38.6°C; heart rate, 112 beats/min; respiratory rate, 24 breaths/min; and oxygen saturation, 90% on room air.
• On examination, the patient is sleeping but arousable to voice and oriented to person only. He has labored respirations with bilateral rhonchi. You order a multiplex PCR test, which is positive for influenza A.
• His oxygen saturation improves to 95% on 2 L/min of oxygen via nasal cannula.
• You wonder how aggressively you should evaluate this patient for complications of influenza, and if antiviral therapy should be started despite his symptom duration…

A 28-year-old woman presents with myalgias, sore throat, dry cough, and fever for 24 hours…

• Her vital signs are temperature, 38.2°C; heart rate, 92 beats/min; respiratory rate, 18 breaths/min; and oxygen saturation, 98% on room air.
• She has no significant past medical history. On examination, she is well appearing and in no distress. Her tonsils are mildly erythematous without significant swelling or exudate. She is breathing comfortably, and her lungs are clear to auscultation.
• She tells you that she is a schoolteacher and requests antiviral treatment so she can return to work.
• You wonder if diagnostic testing will change management, or if this patient would benefit from empiric treatment…

A 2-year-old boy is brought in by his parents after having a 2-minute generalized tonic-clonic seizure at home in the setting of fever, rhinorrhea, and cough…

• He has no significant past medical history. His vital signs are temperature, 39.4°C; heart rate, 124 beats/min; respiratory rate, 26 breaths/min; and oxygen saturation, 99% on room air. He has returned to his baseline mental status.
• On examination, the child is well appearing, with normal capillary refill. His lungs are clear on auscultation. You order a respiratory virus panel, which returns positive for influenza B.
• You wonder if it is appropriate to start this patient on antiviral therapy, and if admission or observation is warranted…