The frequency of clinical variants of Guillain-Barre syndrome in Ferrara, Italy

As the available diagnostic criteria (National Institute of Neurological an d Communicative Disorders and Stroke, NINCDS) for Guillain-Barre syndrome ( GBS) do not permit inclusion of clinical variants (CV) of GBS, there are fe w data on their occurrence and few reports of the overall incidence of the disease. A population-based study in the local health district of Ferrara, Italy in 1981-1993 selected cases fulfilling both NINCDS criteria (NINCDS C BS cases) and CV. The incidence of CV was 0.35 per 100,000 person-years (95 % CI: 0.15-0.68), 0.32 when age-adjusted to the Italian population. No diff erence was found between CV and NINCDS GBS for male/female ratio, mean age at onset, elevated CSF protein content, seasonal pattern, or mean time dela y from first: neurological symptom to maximal severity. A higher frequency of antecedent infections for CV and more frequent serious disease at the na dir time for NINCDS GBS were found. A complete recovery was more frequent f or CV than NINCDS GBS, but no difference was found regarding good outcome ( defined by a satisfactory recovery and resumption of normal functional life ). Since most findings were similar for NINCDS CBS and CV cases, they may h ave similar underlying pathological mechanisms. When diagnostic criteria fo r GBS include CV, the overall disease incidence in the Ferrara district inc reases from 1.87 to 2.21 cases per 100,000 person-years (the contribution o f CV to the overall incidence of CBS is 15.7%). The currently available dia gnostic criteria for GBS, although useful for field studies,may be too rest rictive as they can entail the loss of about 15% of cases.