Dr Julian Lewis: On the specific point of failure to diagnose, until 20 years ago I had never heard of coeliac disease, and then I went out with a young lady who, as a teenager, had repeatedly gone to her GP knowing something was wrong. Coeliac disease was never diagnosed until she suffered something analogous to a stroke, which left her permanently all but unable to read. Although she has bravely developed ​coping strategies over the years, there is no doubt that her life and career have suffered, and she should never have been put in that situation.