How would you approach cytopenias 5 weeks after initial dosing in a young patient with MDS treated with Azacitadine as a bridge to transplant?

Bridging with HMA to transplant in MDS patients is a common practice although it did not show improved outcomes. You will definitely have to r/o other potential causes of pancytopenia (i.e., infections, etc). I would repeat a BM A/Bx to make sure that blasts are not increasing (< 20% and preferably < 10%); and if so, I would expedite transplantation if a donor is available using a myeloablative conditioning regimen (if appropriate).