Differential Diagnosis
The patient's symptoms of headache, fever, nausea, vomiting, and increasing tooth pain, along with signs of papilledema, confusion, and neck stiffness (indicated by flexion of the neck causing hip flexion), suggest a serious intracranial process. Here is the differential diagnosis categorized:
Single Most Likely Diagnosis
- E. Pyogenic Brain Abscess: The combination of fever, headache, nausea, vomiting, and localized signs such as tooth pain (which could be referred pain due to the abscess's location, e.g., in the frontal lobe affecting the trigeminal nerve distribution), along with signs of increased intracranial pressure (papilledema) and altered mental status, makes pyogenic brain abscess a strong consideration. The absence of a history of ear or sinus infections does not rule out this diagnosis, as brain abscesses can arise from other sources, including dental infections or hematogenously from distant sites.
Other Likely Diagnoses
- B. Medulloblastoma: Although less likely given the acute presentation, medulloblastoma, a type of brain tumor, could cause increased intracranial pressure, headache, nausea, vomiting, and altered mental status. However, the presence of fever and the acute onset of symptoms are less typical for a brain tumor.
- D. Viral Encephalitis: This could explain the fever, headache, confusion, and altered mental status. However, the presence of papilledema and the specific pattern of tooth pain might be less typical for viral encephalitis.
Do Not Miss Diagnoses
- C. Subarachnoid Hemorrhage: Although the patient's presentation does not classically suggest subarachnoid hemorrhage (e.g., sudden, severe headache), this diagnosis is critical to consider due to its high morbidity and mortality if missed. The presence of fever and the pattern of symptoms could potentially distract from this diagnosis.
- F. Cavernous Sinus Thrombosis: Given the patient's symptoms of headache, fever, and signs of increased intracranial pressure, along with the potential for facial or dental infections leading to cavernous sinus thrombosis, this diagnosis is crucial not to miss due to its severe consequences.
Rare Diagnoses
- A. Viral Meningitis: While viral meningitis can cause fever, headache, and neck stiffness, the presence of papilledema, localized tooth pain, and the severity of the patient's presentation make this diagnosis less likely. Viral meningitis typically has a more benign course and less frequently presents with such severe signs of increased intracranial pressure.
- Other rare diagnoses might include less common types of brain infections or tumors, but these would be considered based on additional specific findings or risk factors not provided in the scenario.