Chapter 56
Upper Respiratory Tract Infections (Case 48)
Patricia D. Brown MD
Case: A previously healthy 33-year-old woman presents with a 4-day history of sneezing and runny nose accompanied by nasal congestion, sore throat, and a feeling of fullness in the ears. For the past 2 days she has had a cough, which was initially dry but is now productive of yellowish sputum. She denies fever, chills, or dyspnea. She does complain of generalized myalgias and malaise. Her toddler is currently recovering from a “cold.” She states that she feels she has a cold as well and would normally not seek medical attention, but she is leaving on a business trip in the morning and would like to begin antibiotic therapy “just in case” she has a bacterial infection that could worsen while she is on her trip. Her physical exam reveals normal vital signs; she has erythema of the posterior pharynx with tonsillar enlargement but no exudates. The tympanic membranes are mildly erythematous bilaterally, with no evidence of fluid or retraction. There is no palpable lymphadenopathy in the neck, and the lung examination reveals only a few scattered expiratory wheezes bilaterally.
Differential Diagnosis
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Viral rhinosinusitis (VRS) (common cold)
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Acute bronchitis
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Otitis media (OM)
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Acute community-acquired bacterial sinusitis (ACABS)
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Pharyngitis (viral or bacterial)
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Speaking Intelligently
Infections of the respiratory tract are extremely common in both children and adults and are a leading cause of acute-care visits to the physician. Most of these are infections of the upper respiratory tract (URIs), but the possibility of community-acquired pneumonia must also be considered in patients with an illness characterized by acute cough. URIs are more common in the fall to early spring, and the vast majority are due to viruses. Adults can be expected to have two to four colds per year; parents of preschool and young school-aged children experience the highest incidence of URI.
• My first task is to try to differentiate URIs such as the common cold, sinusitis, acute bronchitis, pharyngitis, and OM from lower respiratory tract infections (pneumonia).
• Once I have determined that my patient has an infection confined to the upper respiratory tract (URI), the next challenge is to differentiate viral infection from bacterial infection. This differentiation is important, as viral infections will not require antibiotic therapy, although many patients—such as the woman in the case presented here—will present to the physician with an expectation for an antibiotic prescription.
• The single exception is influenza, which may be treated with antiviral therapy, although the benefits in otherwise healthy adults are very modest.
• Acute respiratory tract infections account for the majority of antibiotic prescriptions given to adults in ambulatory practices in the United States, and many of these prescriptions are given for infections that are viral in etiology.
• In addition to increasing costs and exposing patients to unnecessary risk of untoward medication effects, inappropriate antibiotic use is believed to be an important factor in increasing the prevalence of antimicrobial resistance among bacteria that cause both upper and lower respiratory tract infections, especially Streptococcus pneumoniae.
• Focus on careful elucidation of the constellation of symptoms and the temporal course of the illness.
• The constellation of symptoms is important in pharyngitis, for example, where the presence of cough makes the likelihood of viral infection much greater.
• The temporal course of illness is of critical importance in trying to differentiate VRS from ACABS. Patients with purulent nasal discharge and facial pain or tenderness (especially if unilateral), who are not improving or are worsening after 7 days of illness, are more likely to have a bacterial sinusitis.
• History of sick contacts is also important; sick contacts with URI symptoms support a diagnosis of viral infection, while an adult patient with pharyngitis who has been exposed to a person with documented streptococcal pharyngitis is at higher risk for having this pathogen as the etiology of his or her infection.
• Emphasize that the presence of purulent respiratory secretions simply reflects inflammation (the presence of polymorphonuclear neutrophils [PMNs]), which may be elicited by either viral or bacterial infection.
• In patients with acute coughing illness, the presence of pleuritic chest pain should prompt further investigation to exclude pneumonia.
• Influenza virus can cause VRS and acute pharyngitis.
• Evaluate the temperature, respiratory rate, and pulse.
• Examine the upper respiratory tract, including palpation over the maxillary and frontal sinuses, and carefully examine the posterior pharynx for the presence of tonsillar enlargement, erythema, and exudates.
• Note conjunctival injection.
• Examine the tympanic membranes in adults whose complaints include ear pain or fullness, and palpate the neck for the presence of adenopathy.
• Perform careful auscultation and percussion of the lungs to exclude the presence of focal findings that would suggest pneumonia.
• In patients with severe symptoms suggestive of sinusitis, the presence of periorbital swelling, conjunctival injection, proptosis, or deficits of the extraocular movements suggests extension of infection beyond the sinuses and requires emergent evaluation.
• In a patient with severe symptoms of pharyngitis, diffuse swelling on one side of the neck or asymmetric tonsillar enlargement with medial displacement suggests a suppurative complication such as a peritonsillar abscess.
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• In most patients with acute cough, the absence of any abnormality of vital signs (no fever, tachycardia, or tachypnea) or any focal auscultatory finding on lung examination (focal crackles, bronchial sounds) is sufficient to exclude a diagnosis of pneumonia on clinical grounds. Patients with an abnormality of one of the vital signs listed above or focal findings on auscultation should have a chest radiograph to exclude the possibility of pneumonia.
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• In patients with symptoms suggestive of acute sinusitis, radiographs are not recommended routinely, as they will not assist in the differentiation of viral from bacterial infection. CT of the sinuses is reserved for selected situations, such as when extension of infection beyond the sinuses is suspected.
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• A rapid antigen detection test (RADT) or culture should be performed to confirm the diagnosis of streptococcal pharyngitis; in adults, a negative result on the RADT is sufficient to exclude the diagnosis of streptococcal pharyngitis.
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• Rapid tests are also available for the diagnosis of influenza; however, when influenza is known to be circulating in the community, clinical diagnosis is quite accurate.
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Viral Rhinosinusitis or Common Cold
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