77 year old female, good health, very active. Routine blood test recently turned up high platelets .. Saw Haemotologist, now on Hydroxyurea for 2 months. No cause for high platelets is known. I have chronic sinus problem and have had two surgeries in past for polyp removal. This helps but does not cure, so deal with frequent sinus infections. Have read that an infection can cause high platelets so I am definitely looking into that .. Upcoming appointment with Otolaryngologist that did sinus surgery to check out condition of sinus problem. This was arranged by me with referral from my regular Doctor but not something either she nor the blood specialist would even listen to. This may not turn up anything but I think it is worth checking. Don't want to take Hydroxyurea forever if not necessary.