Individual SNOT-22 Items Aid in Differentiating Between Spontaneous Cerebrospinal Fluid Rhinorrhea and Chronic Rhinosinusitis Without Nasal Polyps

Objectives: Spontaneous cerebrospinal fluid (CSF) rhinorrhea is a diagnostic challenge due to its overlapping symptomatology with other sinonasal diseases. The objective of this study was to investigate whether items on the sinonasal outcome test (SNOT)−22 could suggest a diagnosis of spontaneous CSF rhinorrhea versus chronic rhinosinusitis without nasal polyps (CRSsNP). Methods: A multi-institutional retrospective chart review of patients with spontaneous CSF rhinorrhea and a control group of CRSsNP patients was performed. Individual SNOT-22 scores and domain scores were compared. Results: One hundred fifteen patients were included in both cohorts. Of the patients in the CSF rhinorrhea group, 48% were misdiagnosed as chronic rhinosinusitis (CRS) prior to the correct identification of a CSF leak. On bivariate analysis, the CSF rhinorrhea group scored significantly higher on the SNOT-22 for runny nose (P <.001) and was more likely to designate this symptom as most important (P <.001). The CRSsNP group scored significantly higher in nasal blockage (P <.001), thick nasal discharge (P <.001), facial pain/pressure (P <.001), and in the ear/facial (P <.001) and rhinologic (P =.003) domains. Multivariable logistic regression revealed that runny nose (P <.001) was most predictive of spontaneous CSF rhinorrhea while nasal blockage (P <.001), thick nasal discharge (P <.001), and facial pain/pressure (P =.001) were predictive of CRSsNP after adjusting for relevant confounders. No significant difference was observed in total SNOT-22 scores between groups (P =.676). Conclusions: Spontaneous CSF rhinorrhea is commonly misdiagnosed as other sinonasal pathologies. However, individual SNOT-22 items can help aid in suggesting a CSF leak. Spontaneous CSF rhinorrhea should be suspected in patients who have high SNOT-22 scores for runny nose and report this symptom as most important, but have lower scores related to the other cardinal symptoms of CRS.