IN MY OPINION --- Symptoms may vary, but generally.... if you experience unusual, persistent leg weakness, followed in combination with either severe low back pain or a persistent worsening numbness in your feet, a numbness which may be ascending into the ankles & calves, you should seek medical advice ASAP. GBS is rare, one in one hundred thousand (1:100K). 2% do not survive GBS as a consequence of respiratory failure, usually due to lack of timely, accurate diagnosis. There is a good chance those you encounter have studied GBS, but have never actually encountered a real case of GBS. Don't fall in the 2%. If your healthcare professional does not mention GBS as a possibility, you should definitely mention that you've read that GBS is a potential match for your symptoms. A spinal tap for sufficient fluid sample for lab analysis is required for definitive diagnosis. A high protein level in the fluid will confirm GBS. Rule out GBS before exploring other diagnosis.