Resolution of Chronic Aspiration Pneumonitis following Endoscopic Endonasal Repair of Spontaneous Cerebrospinal Fluid Fistula of the Skull Base: A Case Series

Objective Spontaneous cerebrospinal fluid (CSF) leaks are the rarest type of CSF leaks. Like other kinds of CSF leaks, spontaneous leaks most commonly present with CSF rhinorrhea. Persistent rhinorrhea can be confused for a symptom of rhinosinusitis or allergic rhinitis. Such misdiagnoses cause delay in treatment of the leak and lead to complications and comorbidities. The most common complications described in the relevant literature include meningoencephalocele and meningitis. In the following retrospective case series, the authors aim to demonstrate that a CSF leak can also lead to aspiration pneumonitis, a complication that has not been previously described.

Methods The authors report four patients presenting with pulmonary symptoms including dyspnea, aspiration, chronic cough, shortness of breath, and bilateral groundglass opacities on CT imaging that were all found to be accompanied by a spontaneous CSF leak arising from a skull base defect. Two patients had ethmoidal CSF leaks arising from the fovea ethmoidalis, one had a lateral sphenoidal skull base defect, and one had middle fossa floor skull base dehiscence draining through the eustachian tube. Three patients underwent endoscopic endonasal approaches for skull base defect, while one required a craniotomy. All four underwent CSF leak repair using an autologous fascia lata graft and pedicled nasoseptal flap.

Results All four patients underwent successful repair of a skull base defect and CSF leak with no complications or evidence of recurrence. Upon repair of the spontaneous CSF leak, pneumonitis symptoms were resolved and the ground-glass opacities on CT imaging cleared in all four cases.

Conclusion The authors contend that a diagnosis of CSF leaks should be considered when a patient presents with pneumonitis symptoms that do not alleviate or worsen with treatment.