Differential Diagnosis for Worsening Sore Throat, Congestion, and Chills
Given the symptoms of worsening sore throat, congestion, and chills over 3 days, with negative flu and COVID-19 testing, and negative strep testing, the following differential diagnoses are considered:
Single Most Likely Diagnosis
- Viral pharyngitis: This is the most likely diagnosis given the symptoms and the negative tests for flu, COVID-19, and strep throat. Many viruses can cause these symptoms, and the absence of a positive test for other conditions points towards a viral etiology.
Other Likely Diagnoses
- Sinusitis: The presence of congestion suggests that the sinuses may be involved, and sinusitis can present with similar symptoms, including sore throat due to postnasal drip.
- Mononucleosis (Mono): Although less common, mono can cause sore throat, fever, and fatigue. It's often seen in younger populations and can be diagnosed with a monospot test or EBV antibody tests.
- Allergic rhinitis: If the symptoms are related to allergies, this could explain the congestion and potentially the sore throat if there's significant postnasal drip.
Do Not Miss Diagnoses
- Epiglottitis: Although rare, epiglottitis is a life-threatening condition that requires immediate attention. It can present with severe sore throat, difficulty swallowing, and shortness of breath.
- Lemierre's syndrome: This is a rare but serious condition that starts with a sore throat and can progress to include neck pain and swelling, due to a bacterial infection of the jugular vein.
- Peritonsillar abscess: Despite a negative strep test, a peritonsillar abscess is a possibility, especially if there's significant tonsillar swelling or asymmetry, and severe throat pain.
Rare Diagnoses
- Tuberculosis (TB): Although rare in many parts of the world, TB can cause chronic sore throat and systemic symptoms like chills and fever.
- HIV infection: Acute HIV infection can present with flu-like symptoms, including sore throat and fever.
- Toxoplasmosis: In immunocompromised individuals, toxoplasmosis can cause a variety of symptoms, including sore throat, though it's less common.
Each of these diagnoses should be considered in the context of the patient's overall clinical presentation, medical history, and risk factors. Further testing or consultation may be necessary to determine the exact cause of the symptoms.