Biofilm-associated infection: the hidden face of cerebrospinal fluid shunt malfunction.

Diagnosis of cerebrospinal fluid (CSF) shunt infection is difficult. Growing evidence links this pattern to biofilm-associated infections (BAI). Biofilm may explain the indolent development of the infection, and the poor efficiency of traditional microbiologic methods. We report the case of a patient admitted for hydrocephalus associated to CSF shunt malfunction. None of the clinical, serum, or CSF laboratory findings were in favor of an infectious process. Only scanning electron microscopy (SEM) revealed the presence of biofilm. Hence, despite a broad CSF shunt infection definition, some infections could remain undiagnosed by the traditional approach. This study is the first to provide some direct evidence for bacterial biofilm-associated CSF shunt infection.