[Neurological manifestations in Chikungunya: about 23 cases collected in Reunion Island].

INTRODUCTION: We are reporting 23 cases of patients presenting neurological symptoms in the setting of a chikungunya outbreak that occurred in the Indian Ocean from March 2005 to April 2006. These symptoms were the cause of admission in our ward, mainly via the emergency room. CASE REPORTS: In the acute phase of their illness, 23 patients presented neurological symptoms associated with positive CSF tests (specific IgM or RT- PCR). Clinical manifestations included disrupted behavior or altered mental status in 95% of patients, headache in 30.4%, seizure in 26%, motor dysfunction in 4.3% and sensorial disorders in 8.7%. Outcome was fatal in two patients during their hospitalisation and several months after discharge in three other elderly bedridden patients with altered general status. CSF analysis was sometimes but not always inflammatory. CT or MRI, when done, showed no recent abnormality. EEG disclosed most often of a diffuse moderately slowed activity with no pseudo-periodic or unusual pattern. A few epileptic aspects were seen in known epileptic patients. The outcome of the neurological symptoms was generally good over a few days, contrasting with persisting impairment of general status and severe joint pains leading to a bedridden state and death in three patients.
CONCLUSION: Nervous system involvement was not uncommon during the chikungunya outbreak in Reunion Island in 2005 and 2006. The most frequent expression was moderate confusion occurring during the acute phase of infection. Peripheral nerve involvement in the form of a typical Guillain Barré syndrome was also observed. In general, the neurological outcome was very good. Fatal issues occurring in the early stages or later on (five out of 23 patients) were related to altered general condition in debilitated bedridden elderly patients.