Differential Diagnosis for Headache, Fatigue, Blurred Vision, Sore Throat, and Pain with Swallowing
Single Most Likely Diagnosis
- Viral Pharyngitis: This is the most likely diagnosis given the combination of sore throat, pain with swallowing, and the presence of systemic symptoms like headache and fatigue. The symptoms have been present for approximately 3 days, which aligns with the typical onset and duration of viral pharyngitis.
Other Likely Diagnoses
- Influenza: The symptoms of headache, fatigue, sore throat, and pain with swallowing could also be indicative of influenza, especially during flu season. Blurred vision is less common but can occur due to dehydration or as a side effect of the systemic illness.
- Mononucleosis (Mono): Caused by the Epstein-Barr virus, mono can present with sore throat, fatigue, and fever. Although less common, it could also explain the headache and possibly the blurred vision if there's significant dehydration or a complication like a peritonsillar abscess.
- Strep Throat: While primarily known for causing a sore throat, strep throat can also lead to systemic symptoms like headache and fatigue. The blurred vision might be less directly related but could occur if the patient is dehydrated.
Do Not Miss Diagnoses
- Meningitis: Although less likely, meningitis is a critical diagnosis that must be considered, especially if the headache is severe and accompanied by fever, stiff neck, or confusion. The blurred vision could be a sign of increased intracranial pressure.
- Encephalitis: Similar to meningitis, encephalitis is an inflammation of the brain tissue, usually caused by viral infections. Symptoms can include headache, fever, confusion, and sometimes visual disturbances.
- Temporal Arteritis (Giant Cell Arteritis): This condition, which typically affects older adults, involves inflammation of the blood vessels and can cause headache, visual disturbances (including blurred vision), and sometimes sore throat or jaw pain. It's a medical emergency due to the risk of blindness.
Rare Diagnoses
- Lemierre's Syndrome: A rare condition characterized by a bacterial infection of the throat, followed by a bacterial infection of the jugular vein. It can cause severe sore throat, fever, and systemic symptoms, but it's much less common than viral pharyngitis or strep throat.
- Syphilis (Secondary): In its secondary stage, syphilis can cause a wide range of symptoms, including sore throat, fever, headache, and visual disturbances. However, this would be a rare diagnosis without other specific symptoms like a rash or known exposure history.
- Toxoplasmosis: An infection caused by the Toxoplasma gondii parasite, which can lead to flu-like symptoms, including headache and fatigue. Blurred vision could occur if there's involvement of the eyes (toxoplasmic retinochoroiditis), but this would be an uncommon presentation without specific risk factors or immune compromise.