A young female comes in with persistent unilateral clear nasal discharge 1 month after a fall. What’s the diagnosis? (scroll down for answer)

Answer: CSF leak via defect in the cribriform plate

• Maintain a high suspicion for occult CSF leaks with any recent traumatic history and persistent rhinorrhea or otorrhea
• Send a beta-2-transferrin of the fluid sample (only present found in CSF fluid, perilymph, and aqueous humor)
• Another less commonly used method to test fluid include the “double ring” sign on coffee filter paper (expanding outer CSF ring around a central blood ring) but can generate false positives
• Obtain CT scans with thin cuts through sinuses to detect small cribriform plate defects but may need advanced techniques such as CT cisternography for localization
• High risk for meningitis especially for leaks greater than 7 days and may require neurosurgical intervention (possibly a lumbar drain for CSF diversion to reduce volume and pressure)

 Resources

• Abuabara, A. Cerebrospinal fluid rhinorrhea: diagnosis and management. Med Oral Patol Oral Cir Bucal. 2007 Sep 1;12(5):E397-400.
• Galliard, F. CSF Rhinorrhea. Radiopaedia. Available at https://radiopaedia.org/articles/csf-rhinorrhoea.