Differential Diagnosis #1

Subarachnoid Hemorrhage

Subarachnoid hemorrhage occurs when blood enters the subarachnoid space from the vasculature due to a damaged vessel, either through trauma, a leaky vessel, or a ruptured aneurysm (McCance & Huether, 2015).

Rationale

Because this patient has a history of hypertension and presented with the symptoms of headache, stiff neck, photophobia, nausea, and vomiting, we included subarachnoid hemorrhage as a possible differential diagnosis.

Clinical manifestations of subarachnoid hemorrhage include headache, stiff neck, visual disturbances, nausea and vomiting, focal neurological deficits (McCance & Huether, 2015). Patient with subarachnoid hemorrhage may also present with positive mengingeal signs (Brudzinski’s sign and Kernig’s sign) because blood is irritating to the meninges and can cause inflammation (Berkowitz, 2007). To prevent additional traction to the already-irritated meninges, flexion of the neck will cause flexion of the hip and knees (Brudzinski’s sign), and if a provider flexes the patient’s leg at the hip and attempts to straighten the patient’s knee, she will meet resistance (Kernig’s sign) (Berkowitz, 2007).

The clinical presentation of the patient is due to other pathological processed beyond irritated meninges. The blood covers the arachnoid villi and clogs the ventricular system, preventing reabsorption of cerebrospinalfluid (CSF) and increased intracranial pressure (ICP) (McCance & Huether, 2015). In addition, the hematoma can expand and cause mass effect and brain compression (McCance & Huether, 2015).

Though many of the patient’s symptoms fit this diagnosis, the patient presented with a fever, which is not indicative of acute subarachnoid hemorrhage unless it results from a ruptured mycotic aneurysm (which forms from bacterial endocarditis) (McCance & Huether, 2015). This led us to consider other possible diagnoses.

Subarachnoid hemorrhage is a type of stroke, which is a medical emergency. To learn more about subarachnoid hemorrhage, please click the following link to watch a short video: https://www.youtube.com/watch?v=7O9a4gVnk8E

 

Differential Diagnosis #2

Brain Abscess

A brain abscess is an accumulation of pus in the extradural, subdural, or intracerebral space. Abscesses typically form from contamination during open trauma or neurosurgery or secondary to an adjacent infection such as an ear infection, sinus infection, or osteomyelitis or from a distal infection that travels via blood or CSF (McCance & Huether, 2015).

Rationale

Some of the patient’s symptoms were consistent with brain abscess, so that was included as a differential diagnosis. Signs and symptoms of a brain abscess may include fever, headache, nausea, vomiting, neck pain and stiffness, and nuchal rigidity as well as altered awareness, altered arousal, seizures, motor and sensory deficits, impaired communication, visual disturbances, papilledema, and ataxia depending on the severity and location of the abscess (McCance & Huether, 2015). These symptoms arise from the body’s inflammatory response to infection as well as mass effect and brain compression (McCance & Huether, 2015).

Differential Diagnosis #3

Migraine

A migraine is a moderate to severe headache that lasts 4 to 72 hours and presents as unilateral pain, throbbing pain, or pain worsening with activity and may be accompanied by nausea, vomiting, photophobia, visual disturbances, and/or phonophobia (McCance & Huether, 2015).

Rationale

The patient’s presentation matches many of the clinical manifestations of migraine. The specific pathophysiology of migraine is not well understood, but current theory suggests that the pain is from trigeminal nerve irritation from neurologic, vascular, hormonal, and neurotransmitter signals (McCance & Huether, 2015). With the exception of fever, this diagnosis is consistent with the patient’s presentation. However, migraine can only be diagnosed if the symptoms are consistent with the above mentioned and all other headache-causing disorders have been ruled out (McCance & Huether, 2015).

Correct Diagnosis

Meningitis

Because the patient’s symptoms were concerning for subarachnoid hemorrhage and brain abscess, we performed a CT scan which ruled out these diagnoses. To determine whether the patient’s symptoms were from a primary headache or were secondary to another neurological illness, we performed a lumbar puncture. The patient’s presentation paired with the increased protein, white blood cells, and C-reactive protein in the patient’s CSF led us to diagnose the patient with meningitis. We requested to add on additional lab tests to the CSF samples to help differentiate if the meningitis was viral, bacterial, fungal, or aseptic. We admitted the patient with droplet precautions ordered and consulted the infectious disease service for treatment recommendations.