Differential Diagnosis
- Single most likely diagnosis
- Cluster headaches: The patient's symptoms of severe, sharp pain behind one eye, accompanied by eyelid edema, lacrimation, conjunctival injection, and nausea/vomiting, are classic for cluster headaches. The episodic nature of the headaches, occurring in clusters, further supports this diagnosis.
- Other Likely diagnoses
- Migraines: Although the patient denies sensitivity to noise or light and auras, migraines can present with unilateral pain and associated symptoms like nausea and vomiting. However, the lack of sensitivity to noise or light and the specific pattern of headache occurrence make migraines less likely.
- Trigeminal neuralgia: This condition can cause severe, sharp pain in the face, but it typically does not have the same episodic pattern as cluster headaches and is not usually associated with eyelid edema, lacrimation, and conjunctival injection.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Temporal arteritis: This condition can cause headaches, but it is typically associated with jaw claudication, visual disturbances, and an elevated erythrocyte sedimentation rate (ESR). Although the patient's age and symptoms do not strongly suggest temporal arteritis, it is essential to consider this diagnosis due to its potential for serious complications if left untreated.
- Pituitary apoplexy: This rare condition can cause sudden, severe headaches, but it is typically associated with other symptoms like visual disturbances, altered mental status, and hormonal imbalances. The patient's symptoms and physical examination do not strongly suggest pituitary apoplexy, but it is crucial to consider this diagnosis due to its potential for serious complications.
- Rare diagnoses
- Paroxysmal hemicrania: This rare condition can cause severe, unilateral headaches with associated symptoms like lacrimation and conjunctival injection. However, it is less common than cluster headaches and typically responds well to indomethacin.
- SUNCT (Short-lasting Unilateral Neuralgiform headache attacks with Conjunctival injection and Tearing) syndrome: This rare condition can cause severe, unilateral headaches with associated symptoms like conjunctival injection and tearing. However, it is less common than cluster headaches and typically has a different pattern of headache occurrence.
Next Best Step in Management
Based on the likely diagnosis of cluster headaches, the next best step in management would be to provide symptomatic relief with oxygen therapy and consider sumatriptan for acute attacks. Therefore, the correct answer is B. Sumatriptan and oxygen therapy.