Common Colds for PA
Common colds for the Physician Assistant Licensing Exam
Pathophysiology
- Viral Infection:
- The common cold is primarily caused by viral pathogens, with rhinoviruses being the most frequent (50% of cases). Other causes include coronaviruses, adenoviruses, and respiratory syncytial virus (RSV).
- These viruses infect the nasal and upper respiratory tract, triggering an immune response that leads to inflammation and mucus production.
- Transmission:
- Spread occurs via direct contact with contaminated surfaces or aerosolized droplets from coughs and sneezes. The virus enters through the nasal or conjunctival mucosa.
Clinical Features
- Nasal Congestion and Rhinorrhea:
- The most common symptoms, initially presenting as watery discharge, which may later thicken and become purulent.
- Sore Throat:
- A mild sore throat or pharyngitis is common, especially early in the illness.
- Cough:
- A nonproductive cough may develop, often worsening due to postnasal drip.
- Sneezing and Malaise:
- Sneezing is frequent, and mild fatigue often accompanies other symptoms.
- Fever:
- Fever is uncommon in adults but may occur in children.
Diagnosis
- Clinical Diagnosis:
- Based on characteristic symptoms such as nasal congestion, rhinorrhea, and absence of high fever. There is no need for laboratory testing unless there is concern for other causes like influenza or COVID-19.
- Differential Diagnosis:
- Differentiating from influenza (more systemic symptoms), sinusitis (prolonged nasal congestion), or allergic rhinitis (clear nasal discharge without systemic symptoms) is important.
Management
- Symptomatic Treatment:
- Nasal decongestants (e.g., oxymetazoline) relieve congestion but should be used for no more than 3-5 days to avoid rebound congestion.
- Antihistamines may alleviate sneezing and rhinorrhea, particularly first-generation agents (e.g., diphenhydramine).
- Analgesics like acetaminophen or ibuprofen can reduce headache, body aches, and fever.
- Supportive Care:
- Hydration, rest, and humidification help ease symptoms. Saline nasal sprays help clear mucus.
Key Points
- The common cold is caused by viral infections, primarily rhinoviruses, and is transmitted through direct contact or respiratory droplets.
- Symptoms include nasal congestion, rhinorrhea, sore throat, and cough, with fever uncommon in adults.
- Diagnosis is clinical, based on symptom presentation, and treatment focuses on symptom relief with decongestants, antihistamines, and hydration.
- Antibiotics are not indicated for viral colds, and prevention relies on hand hygiene and respiratory hygiene practices.