Increased prevalence of aspiration pneumonitis in spontaneous cerebrospinal fluid leaks

Aspiration pneumonitis (AP) secondary to cerebrospinal fluid (CSF) leak is underestimated and rarely discussed. This study aimed to evaluate the association between AP and CSF leaks.

Clinical and surgical characteristics of CSF leak patients with and without AP between January 2010 and December 2022 were included and compared.

This study included 159 patients, 16 with CSF otorrhea and 143 with CSF rhinorrhea. Among them, 40 (25.2%) had AP. Bilateral pneumonitis was identified in 32 cases, of which 11 showed severe pneumonitis in the right upper lung lobe. Twenty-one (52.5%) asymptomatic and 19 (47.5%) symptomatic cases were documented. The major clinical manifestations included cough (n = 19, 47.5%) and expectoration (n = 9, 22.5%). The prevalence of pneumonitis was significantly higher in the spontaneous group than in the traumatic group. High-flow CSF leak was associated with AP (42.5% vs. 16.8%, p = 0.001). No significant differences were identified in defect locations between patients with and without AP. Patients with pneumonitis had a higher prevalence of meningitis (32.5% vs. 12.6%, p = 0.003). Multiple logistic regression results revealed that meningitis, spontaneous and high-flow CSF leaks are independent factors for AP occurrence. Both the CSF leak and pulmonary complications resolved following successful surgical repair.

AP secondary to CSF leaks is frequently underdiagnosed, with a higher incidence identified in spontaneous cases. The occurrence of AP was associated with high-flow CSF leak.

A pneumonitis rate of 25.2% in cerebrospinal fluid (CSF) leak patients was reported for the first time. A higher prevalence of aspiration pneumonitis was identified in spontaneous CSF leak. Meningitis, spontaneous and high-flow CSF leaks are independent factors for aspiration pneumonitis occurrence.