Differentiation of ALL from AML

on 7.2.09 with 0 comments

  • Auer rods

    • Red toothpick looking things in the cytoplasm

    • They are abnormal azurophilic granules

    • Intensely peroxidase (+)

    • Say for sure that you are looking at myeloid differentiation

  • Telling ALL from AML

    • It’s important to tell them apart because they are treated very differently

    • Myeloblasts tend to have more delicate chromatin, prominent or multiple nucleoli, and fine azurophilic granules in the cytoplasm…Auer rods are a sure thing

    • TdT

      • Terminal deoxynucleotidyl transferase, a DNA polymerase

      • Seen in 95% of ALL and <>

    • Myeloid monoclonal antibodies (CD33, CD13, CD11, etc) are reactive in most (80%) of AML; they are rare in ALL and when they are there it’s not good

    • Special stains

      • PAS: “block” positivity in lymphoblasts, diffuse positivity in erythroblasts

      • MP: myeloblasts

      • SB: myeloblasts

      • NSE: monoblasts

Category: Medical Subject Notes , Pathology Notes



Post a Comment