Hello! Thank you for asking on HCM! I read your question carefully and understand your concern. Optic neuritis is an autoimmune disorder, causing inflammation of the tissues surrounding the eye. The phenomena causing your fingernails to turn purple and hurt, is probably Raynaud s syndrome, which is commonly related to autoimmune disorders. Regarding mitral valve prolapse, it can be an incidental finding, not related to the above disorders. But, when combined with these other disorders, it raises high suspicions for a connective tissue disorder ( like systemic lupus erythematosus or scleroderma, etc.), which are autoimmune disorders. I recommend consulting with the GP for a careful physical examination, and performing some lab tests like: complete blood count, inflammation tests(PCR, fibrinogen, sedimentation), kidney and liver function tests, blood electrolytes, thyroid hormone levels (sometimes thyroid gland is affected too), etc.. Further lab investigations towards autoimmune disorders (like ANA, ANCA, ENA, RF, etc) may be necessary to establish the possible diagnosis. Another diagnostic test, that I would recommend is a brain MRI to rule out possible multiple sclerosis. Hope to have been of help! Best regards, Dr. Iliri