Cerebrospinal fluid leakage-associated bacterial meningitis diagnosed by evaluating glucose concentration in nasal discharge and cerebrospinal fluid: A two-case series.

Cerebrospinal fluid (CSF) leakage can contribute toward the development of bacterial meningitis. Although the diagnosis of CSF leakage is often challenging, it is essential for determining the need for surgical repair to prevent recurrent meningitis. Measurement of glucose levels in nasal discharge is a conventional and low-cost screening method for CSF rhinorrhea; however, its reliability is limited, as various factors can lead to both false-positive and false-negative results. Herein, we report two cases with bacterial meningitis wherein glucose concentrations were measured in nasal discharge and CSF. In both cases, glucose levels were elevated in the nasal discharge and were nearly identical between the nasal discharge and CSF (case 1: 55 mg/dL in nasal discharge vs. 54 mg/dL in CSF; case 2: 64 mg/dL vs. 64 mg/dL, respectively). These findings suggested the presence of CSF rhinorrhea, which was subsequently confirmed by detailed imaging studies or nasal endoscopy. We highlight the clinical significance of nasal glucose measurement in patients with bacterial meningitis and suggest that simultaneous measurement of CSF glucose levels may provide complementary information with this simple screening method.