An important diagnosis to consider in recurrent meningitis
A 49-year-old Greek Cypriot male was referred to us with a history of four episodes of meningitis over the past 15 years (1998, 1999, 2002 and 2009). The first three episodes had been treated elsewhere, each time presenting with headache, fever, photophobia but no rash. Though no bacterial diagnosis was ever made and no organism isolated, his episodes were associated with high cerebrospinal fluid (CSF) protein and CSF neutrophil infiltrate. He responded well to intravenous antibiotic treatment on each occasion with no neurological deficit. Computerized tomography (CT) and magnetic resonance imaging (MRI) head imaging had not detected the cause of his recurrent meningitis.\nHe had had two Staphylococcus aureus infections of his umbilicus in 2002 and 2009 but otherwise his medical history was unremarkable. There was no history of head trauma nor of recurrent ear or sinus infections. He did report some non-specific upper respiratory tract symptoms but none suggestive of CSF rhinorrhoea.\nDetailed investigation of his immune system revealed low mannose-binding lectin (MBL) levels (0.06 mg/L, normal range 1.0–4.0 mg/L). The rest of his humoral and cellular immune tests were normal. A coronal CT sinus scan done to investigate his non-specific upper respiratory tract symptoms showed a 4 × 3 mm defect in the cribriform plate adjacent to the vertical attachment of the middle turbinate, a relatively common site for ‘congenital’ defects (). A small rim enhancing CSF intensity sac was shown on MRI just beneath the cribriform plate defect, consistent with a meningocoele. This was confirmed at surgery. The defect was surgically repaired with temporalis fascia and inferior turbinate mucosa by an endonasal endoscopic route.