I can relate to this. My daughter developed sensitivities post chickenpox and glandular fever. Seems to be linked to liver/ sulfoxidation/ sulfation ( phase 1/2 detox sysyems)which impacts methylation, hormone synthesis, glutathione availability. Recent H. Pylori can be linked back to liver function and gut health ( sulphate availability for mucin synthesis). Even joint pain can be related back to this. Interestingly my aunt who has ME had jaundice when born, hepititis when younger. Genetic disposition may be , in our case related to cysteine/ methionine and sulfur pathways.