ABSTRACT
INTRODUCTION: Although Guillain-Barré syndrome is rare, a marked increase in incidence was observed during the 2016 Zika outbreak in the Americas, with no direct causal relationship being apparent in all cases. METHODS: Cases of febrile exanthematous disease and acute flaccid paralysis were reviewed during the period from 1 August to 15 December, 2016; clinical and biochemical assessment was performed for each case to identify Zika-related Guillain-Barré syndrome. RESULTS: During the study period, we identified 8 patients (6 men and 2 women) with Zika-related Guillain-Barré syndrome, with the most affected age group being 50-59 years. The highest incidence was in the month of September, with 7 cases. The most frequent symptoms were rash and conjunctivitis, followed by fever. The most common presentation was symmetrical ascending paralysis, present in 7 cases. Cranial nerve VII was the most frequently involved nerve. Only 2 patients presented albuminocytologic dissociation. RT-PCR returned negative results for Zika virus in all patients. All patients received intravenous immunoglobulin and all had a good prognosis. None warranted mechanical ventilation. No deaths were recorded. The cumulative incidence rate was 3.9%, monthly incidence was between 0.04 and 2 cases/month. CONCLUSIONS: Cases of Guillain-Barré syndrome increased during the Zika outbreak, with an increase in incidence and number of cases per month; however, a direct causal relationship between the 2 conditions could not be demonstrated.
