Hi RinJin,
My case is a little similar to yours although my platelets are falling slower. I was around 120K at 20, and now my counts are around 40K at 38 (so about a 4K decrease per year).
Do you have bleeding symptoms or not ? If you don’t, a 48K count is usually not a problem and doctors probably won’t want to treat you for now.
The important thing is to have a competent doctor following your case.
In my case, when my counts dropped too low during pregnancies, they tried prednisone and IVIG and my count didn’t go up. Combined with a few other factors, they thought in might be genetic and I’m now waiting for some genetic test results. Preliminary findings seem to indicate it really is a genetic disorder.
ITP is a diagnosis of exclusion, if you’re having doubts, you should discuss them with your doctor(s).
Could you provide a few more details about your condition? I’ve been trying to find other people with steadily dropping platelet counts but I haven’t had much luck. Have your platelet counts always been under 150K? Do other people in your family have low platelets, or bleeding symptoms?