A 47-year-old man comes to the office in mid-January due to persistent high-grade fever, headache, and severe myalgias that began abruptly 4 days ago. The patient also has sore throat, nonproductive cough, and mild nasal congestion but no shortness of breath or chest pain. It has been >5 years since his last appointment, and he is not up to date on health maintenance or immunizations. The patient has no chronic medical problems, takes no medications, and has no known drug allergies. Temperature is 38.5 C (101.3 F), blood pressure is 135/80 mm Hg, pulse is 88/min, and respirations are 16/min. Oxygen saturation is 98% on room air. Physical examination shows a mildly erythematous oropharynx with normal tonsils. No significant cervical lymphadenopathy is present. Breath sounds are clear and equal bilaterally with no dullness to percussion or egophony. Heart sounds are normal. Which of the following is the most appropriate next step in management of this patient?
Distinguishing features of common upper respiratory illnesses | |||
Viral upper respiratory syndrome | Influenza | Streptococcal pharyngitis | |
Onset of symptoms | Slow, stepwise, migratory, or evolving | Abrupt & often dramatic | Variable |
Upper respiratory symptoms | Rhinorrhea, coryza, sneezing, mild pharyngitis | Usually mild | Predominantly pharyngeal symptoms |
Systemic symptoms | Usually mild | Prominent with possible high fever, myalgias, headache | Variable with possible fever & myalgias |
Examination findings | Nasal edema with normal or slightly erythematous pharynx | Variable but often unremarkable | Pharyngeal erythema, tonsillar hypertrophy & exudates, tender cervical lymph nodes |
Influenza is a seasonal respiratory infection with peak prevalence in January and February. Approximately 1-5 days after inoculation, patients abruptly develop systemic (fever, malaise, myalgias, headache) and upper/lower respiratory (rhinorrhea, sore throat, nonproductive cough) symptoms. Physical examination and laboratory studies are often normal but may show pharyngeal erythema (without exudates) and mild alterations in leukocyte count (low early, high late).
For adults with suspected or confirmed influenza, treatment is as follows:
(Choice A) Patients who are moderately or severely ill should not be given the influenza vaccine until symptoms abate.
(Choice B) Streptococcal pharyngitis is characterized by sore throat with tonsillar exudate, cervical adenitis, and fever. Headache, myalgias, cough, and rhinorrhea are more characteristic of a viral infection (eg, influenza). A rapid streptococcal antigen test would not be useful and is not indicated in this patient with only a single Centor criterion (fever).
(Choice C) Azithromycin may be prescribed for community-acquired pneumonia in areas with low rates of Streptococcus pneumoniae macrolide resistance. Although atypical pneumonias (eg, Mycoplasma pneumoniae) share many symptoms with influenza and can be treated with azithromycin, the abrupt onset of symptoms makes influenza far more likely.
Educational objective:
Patients with influenza abruptly develop systemic (fever, malaise, myalgia, headache) and upper/lower respiratory (rhinorrhea, sore throat, nonproductive cough) symptoms. In the absence of risk factors (eg, age ≥65, chronic medical conditions) for influenza complications, most adults do not require testing and are treated symptomatically.