About the Diagnosis of the Common Cold

Diagnosis

Based on experience, the common cold is often diagnosed even without a doctor’s diagnosis. Even now, there is no method more effective or better than diagnosis based on symptoms.

1. Temporary symptoms As already introduced, symptoms are limited to the upper respiratory tract. If a runny nose is the main symptom, it may be confused with allergic rhinitis, but the difference is that allergic rhinitis recurs frequently and lasts a long time. Most important of all is identifying complications such as secondary bacterial sinusitis and otitis media. In sinusitis, there is nasal congestion, purulent runny nose, fever, general weakness, pain in the sinuses, and tenderness when pressing on the face.

2. Physical examination In most cases, the doctor’s examination is normal, but there may also be redness, swelling, or secretions in the throat. In conjunctivitis, the conjunctival blood vessels become enlarged and the eyes appear red. If there is severe inflammation and exudate in the pharynx, group A streptococcus, adenovirus, herpes simplex virus, ulcerative membranous pharyngitis, infectious mononucleosis, and diphtheria may be suspected. In acute pharyngitis, it is necessary to distinguish it from viral pharyngitis to decide whether antibiotic treatment is needed. Tonsillar exudate, painful lymphadenitis, skin rash, and conjunctivitis may be helpful, but they are not very accurate. Exudate is rare in viral colds or influenza.

3. Culture test Because there are no distinctive symptoms depending on each causative virus or bacterium, a culture test must be performed when the cause is to be identified. In acute pharyngitis, most causes are viral, but about 5–15% are due to group A streptococcus, so throat culture has value in deciding whether antibiotic treatment is needed; therefore, it is not performed in all patients with acute pharyngitis.

4. Rapid antigen test and measurement of anti-streptococcal antibody titers In cases caused by group A streptococcus, a rapid antigen test for the streptococcal cell wall can be helpful along with throat culture, but a negative test does not mean that the bacterium is absent, so culture must be repeated. It is used when a prompt diagnosis is needed because complications such as acute rheumatic fever and glomerulonephritis may occur later, but it is not widely used in Korea. Anti-streptococcal antibody titers are tested, but because they rise late after infection and remain elevated for a long time, they are not suitable for diagnosing acute pharyngitis.

5. Other For chronically persistent cough, chest X-rays are performed, and for sinusitis, nasal endoscopy, sinus X-rays, sinus computed tomography, and iron methods are available.

So far, I have explained the diagnosis of the common cold. In the next part, we will look at the treatment and prevention of the common cold.

Source: Korea Disease Control and Prevention Agency, National Health Information Portal