Differential Diagnosis for Fever and Severe Headache
The patient's presentation of fever and severe headache that resolves on its own can be approached by considering various potential causes, categorized for clarity and emphasis on critical diagnoses.
Single Most Likely Diagnosis
- Viral meningitis: This condition often presents with fever, headache, and sometimes neck stiffness. It is usually self-limiting and can resolve without specific treatment, making it a plausible cause for the symptoms described.
Other Likely Diagnoses
- Tension headache or migraine: While these conditions are typically not associated with fever, certain viral infections can trigger such headaches, and the fever could be coincidental or part of a viral syndrome.
- Sinusitis: An infection of the sinuses can cause headache and fever, and if the infection is mild, it might resolve on its own with supportive care.
- Viral gastroenteritis or influenza: Both can present with fever and headache, among other symptoms, and often resolve without needing specific treatment.
Do Not Miss Diagnoses
- Bacterial meningitis: Although less likely if the symptoms resolve on their own, bacterial meningitis is a medical emergency that requires prompt treatment. Early stages might mimic viral meningitis, but the condition can rapidly deteriorate.
- Subarachnoid hemorrhage: A sudden, severe headache (often described as "the worst headache of my life") can be a sign of a subarachnoid hemorrhage, which is a life-threatening condition.
- Encephalitis: Inflammation of the brain tissue, usually due to a viral infection, can present with fever, headache, and altered mental status. It requires urgent medical attention.
Rare Diagnoses
- Temporal arteritis: This condition, which involves inflammation of the blood vessels in the head, can cause severe headache and fever, especially in older adults.
- CNS vasculitis: Inflammation of the blood vessels in the central nervous system can lead to a variety of symptoms, including headache and fever, but it is relatively rare.
- Idiopathic intracranial hypertension (IIH): Characterized by increased pressure within the skull without an apparent cause, IIH can present with headache and sometimes fever, although it's more commonly associated with other symptoms like vision changes.