Oligosymptomatic dengue infection: a potential cause of Guillain Barré syndrome.

BACKGROUND Dengue infection may cause neurological manifestations such as encephalitis, myelitis, mononeuropathies, acute disseminated encephalomyelitis, and Guillain Barré syndrome (GBS). In endemic regions, the infection course can be oligosymptomatic making difficult the diagnosis of the neurological picture associated with dengue infection. OBJECTIVE To report dengue infection and GBS association, even in oligosymptomatic cases of this infection. METHOD During the dengue epidemic in Rio de Janeiro city we looked for GBS cases, testing IgM antibodies for dengue and dengue polymerase chain reaction (PCR) in the cerebrospinal fluid (CSF) and serum. RESULTS We report seven cases (46.6%), presenting dengue positive IgM in serum but with poor or without clinical symptoms of the previous infection. Two of them had also positive IgM antibodies in CSF. CONCLUSION These data show that search for dengue infection should be a routine in GBS cases living in endemic areas.