Guillain-Barré syndrome (GBS) has a profound impact on patients and their families. Researchers have made considerable progress in understanding the disease mechanisms. Unfortunately these achievements have not resulted in finding better treatments for GBS. The current standard treatment of GBS with either intravenous immunoglobulins (IVIg) or plasma exchange (PE) has not changed in the last 30 years, while more effective treatments are still needed. In 2012 an international team of expert neurologists and scientists decided to join forces and start the International GBS Outcome Study (IGOS), aiming to collect the world’s largest high quality data/biobank for further research. The overall objectives of IGOS are

1. to better understand the cause of GBS and factors influencing disease course, 
2. to improve the diagnostic criteria for early recognition of GBS,
3. to develop prognostic models to predict the clinical course of individual patients and
4. to stimulate the conduct of studies finding better treatments for GBS.

The IGOS Consortium consists of researchers and clinicians from 143 centres in 21 countries across 5 continents. All patients within the diagnostic spectrum of GBS are included irrespective of age, disease severity and treatment, within two weeks from the onset of weakness. Data are collected prospectively at eight standard time points during follow-up of 1 to 3 years, including clinical symptoms and signs and patient questionnaires about the residual complaints and the impact on their lives. In addition, nerve conduction studies and biomaterials (serum and cerebrospinal fluid (CSF)) were collected for future biomarker studies.

Key findings of the IGOS-consortium include

1. novel insights into disease pathways,
2. the finding of major between-region variation in patient demographics,
3. diversity between patients regarding clinical variants, disease severity, practice of treatment, clinical recovery and long-term complications, complaints and impact of disease.

Ongoing and future studies will leverage these insights to compare the effectiveness of treatments and ultimately improve outcome for GBS patients. All published results can be found here.