Differential Diagnosis for Persistent Sore Throat
Single Most Likely Diagnosis
- Viral Pharyngitis: This is the most common cause of a sore throat and can persist for up to 10 days without fever. The lack of fever and the duration of symptoms make this a likely diagnosis.
Other Likely Diagnoses
- Strep Pharyngitis (GABHS): Although fever is often present, some cases of streptococcal pharyngitis can occur without fever. The absence of fever does not rule out this diagnosis, especially if other symptoms like exudative tonsillitis are present.
- Allergic Pharyngitis: Allergies can cause chronic sore throat without fever, especially in individuals with seasonal allergies or postnasal drip.
- Irritant-induced Pharyngitis: Exposure to irritants such as smoke, pollution, or chemicals can lead to a persistent sore throat without fever.
Do Not Miss Diagnoses
- HIV Infection: A persistent sore throat can be an early symptom of HIV infection. Although not common, missing this diagnosis can have significant consequences.
- Tuberculosis (TB): TB can cause a chronic sore throat, especially in individuals with risk factors such as immunocompromised status or recent travel to endemic areas.
- Lymphoma or Other Malignancies: Although rare, a persistent sore throat can be a symptom of lymphoma or other head and neck cancers. Early detection is crucial for effective treatment.
Rare Diagnoses
- Lemierre's Syndrome: A rare condition characterized by a sore throat followed by neck pain and fever, caused by Fusobacterium necrophorum. Although it often presents with fever, some cases may not.
- Diphtheria: A bacterial infection that can cause a persistent sore throat, although it is rare in areas with high vaccination rates.
- Gonococcal Pharyngitis: A sexually transmitted infection that can cause a sore throat, typically without fever. This diagnosis should be considered in individuals with a history of high-risk sexual behavior.