Platelet antibody

Hello, 16 month old daughter was diagnosed with ITP on March 4th, a few days ago her hematology did PLATELET ANTIBODY, DIRECT (IGG)
Plt Associated Anti-IIB/III positive Plt Associated Anti-IB/IX positive
Plt Associated Anti-IA/IIANegative
Do you guys have any clue about the meaning of the reults?
Thank you

These are tests for antibodies against molecules which are known to be potentially on platelets. The positive antibodies test could indicate autoimmune activity against platelets. As of now I do not believe positive or negative platelet antibody tests alter course of treatment, but help to confirm ITP.

Before the results, her hemo wants to do a bone marrow biopsy, but after the results I hope doctor change his mind about doing a biopsy!!!

Angelito, the immune system is very complex. Those 3 tests identify which antibody groups are potentially attacking platelets. There is a lot of good general information on Wikipedia:
... "Most often these antibodies are against platelet membrane glycoproteins IIb-IIIa or Ib-IX, and are of the immunoglobulin G (IgG) type." ...
en.wikipedia.org/wiki/Immune_thrombocytopenic_purpura

I suspect that your doctor was trying to eliminate familial/congenital Thrombocytopenia as a possible diagnosis. One would expect all three to be negative in that situation. See the end of this study's abstract:
"Prospective evaluation of a new platelet glycoprotein (GP)-specific assay (PakAuto) in the diagnosis of autoimmune thrombocytopenia (AITP)"
www.ncbi.nlm.nih.gov/pubmed/15726595

Bone marrow biopsy is a very common approach to ITP diagnosis, it's to ensure there is no other cause like cancer or a different rare blood condition. I had one done and it is minimally invasive and I recovered quickly and with little to no pain.

Though it sounds scary, it's arguably one of the best tools to make sure they diagnose your daughter correctly.