Can pseudotumor cerebri (idiopathic intracranial hypertension) cause sacroiliitis?

Pseudotumor Cerebri Does Not Cause Sacroiliitis

Pseudotumor cerebri (idiopathic intracranial hypertension) does not cause sacroiliitis—these are completely unrelated conditions affecting different anatomical systems with distinct pathophysiologic mechanisms.

Why These Conditions Are Unrelated

Pseudotumor Cerebri Pathophysiology

• Pseudotumor cerebri is a syndrome of elevated intracranial pressure of unknown cause that predominantly affects obese women of childbearing age 1, 2
• The pathophysiology involves intracranial venous hypertension and/or increased cerebrospinal fluid outflow resistance, often related to obesity 2
• The condition produces symptoms and signs exclusively related to increased intracranial pressure, including papilledema, headache, visual disturbances, pulsatile tinnitus, and diplopia from sixth nerve palsy 1, 3

Clinical Manifestations of Pseudotumor Cerebri

• Headache occurs in nearly 90% of patients, typically holocephalic or unilateral throbbing, worse in the morning after supine positioning 4
• Visual disturbances including transient visual obscurations are common 4
• There are no focal or lateralized neurological deficits such as hemiparesis or sensory changes in the extremities 4
• Radicular neck and back pain with extremity symptoms do not occur in pseudotumor cerebri 4

Sacroiliitis Is a Musculoskeletal/Inflammatory Condition

• Sacroiliitis involves inflammation of the sacroiliac joints in the pelvis
• It is associated with spondyloarthropathies, inflammatory bowel disease, infections, or mechanical stress
• The pathophysiology involves joint inflammation, not intracranial pressure changes

Important Clinical Distinction

If a patient presents with both elevated intracranial pressure findings AND sacroiliitis, consider alternative diagnoses:

• Leptomeningeal metastases can present with multifocal signs including focal or irradiating neck and back pain, radicular signs with weakness, and sensorimotor deficits of extremities 4
• Systemic inflammatory conditions (e.g., sarcoidosis, Behçet's disease) can affect both the central nervous system and joints, but this would not be idiopathic intracranial hypertension
• Cervical spine pathology should be evaluated with cervical spine MRI if radicular symptoms are present 4

Common Pitfall to Avoid

• Do not attribute musculoskeletal symptoms to pseudotumor cerebri simply because a patient has been diagnosed with this condition 4
• Evaluate sacroiliitis and pseudotumor cerebri as separate entities requiring distinct diagnostic workup and treatment approaches