Dear Ask The Doctor: Hello: I'm a 42-year-old female of healthy weight and my BP is always low end of normal. I work in a sedentary job but I take a brisk walk twice a day. Five weeks ago I noticed a rash of hundreds of pinpoint-sized dots on parts of my lower legs. They look to me like petechiae. Over the weeks, old clusters of dots have faded while fresh ones keep appearing. The same day the rash appeared I happened to have a CBC as part of a routine physical. My platelet count was a bit below range at 125. Also, my iron was a tiny bit low (67), although I've been on iron supplements since three years ago when it was 29. My doctor doesn't know what's causing the rash but believes it will eventually go away on its own. She does not feel it is related to the platelet count because other tests are normal and she says two other clotting systems would be working even if the platelets are low. I have a number of spider veins on my lower legs and a couple of places where there seems to be permanent small bruising but she does not believe this is related to the rash. I should also mention that my cervical lymph nodes were checked by ultrasound after my doctor thought one felt enlarged during the routine physical. Everything was normal there. My doctor has recommended I get my blood tested every three months until the platelet count returns to normal, and not to worry about the rash. Is this the right course of action? At one point would it be a good idea to see a hematologist? I really like my doctor as a person, but I confess I don't always have faith in her as a diagnostician because she missed my shingles (told me the pain and swelling on my scalp was bug bites from gardening) and my bronchial spasms (told me post-nasal drip wouldn't cause that, although the allergist she referred me to diagnosed that this was the cause). I would never have known about the low platelet count if I hadn't been in to see her about the rash - the receptionist said over the phone that the count was normal. As a result, I tend to have anxiety that important things can be missed, and I dislike feeling this way.
Dear Lisa: I can understand your concern. The tiny pin-point rash that you've noticed on your legs are petechiae on the skin as a result of bleeding under the skin. Petechiae result when tiny capillaries bleed (hemorrhage), leaking blood into the skin. Petechiae may result from abnormalities in the blood-clotting mechanism or in the cells that help your blood to clot (platelets), resulting in low platelet counts (thrombocytopenia). There could be numerous causes of low platelet count including certain viral infections, medications, lupus, rheumatoid arthritis, leukaemia and idiopathic thrombocytopenic purpura. A normal platelet count is 150,000 to 450,000 platelets per microliter of blood. A count of less than 150,000 platelets per microliter is lower than normal. But the risk for serious bleeding doesn't occur until the count becomes very low—less than 10,000 or 20,000 platelets per microliter. Your platelet count of of 125 (I'm presuming 125,000) indicates mild thrombocytopenia.
Mild thrombocytopenia often doesn't require treatment. However if your platelt count is persistently low or decreasing, further workup will be required. I would recommend that you eat plenty of berries and tomatoes, consume food rich in omega-3 fatty acids and take vitamin C tablets. You can also eat vitamin-rich foods such as oranges, kiwi fruit and cabbage. The recommended dosage of vitamin C is 500mg once a day.