Oral and Maxillofacial Surgery (OMFS) Board Practice Exam

Beta-2 transferrin is a specific biomarker that is used to confirm the presence of a cerebrospinal fluid (CSF) leak. This protein is not found in serum but is exclusive to CSF and is detectable in the presence of a leak. It is a reliable indicator because its detection in a fluid sample (such as nasal secretions or fluid collected during a suspected leak) strongly suggests that the fluid is indeed CSF rather than other bodily fluids.

Other factors, like the presence of glucose, sodium, or protein in the fluid, can vary in concentrations and might not be specific to CSF. Glucose levels can be normal in some conditions, and while protein levels can be elevated in various inflammatory or traumatic conditions, these markers are not exclusive to CSF. Sodium is also a standard electrolyte present in many body fluids, limiting its specificity for diagnosing CSF leaks. Therefore, beta-2 transferrin is the most accurate and specific biomarker for confirming a cerebrospinal fluid leak.