<prompt> Myeloperoxidase MPO and Periodic acid schiffs PAS are the two basic cytochemical stains, commonly used in diagnosis and typing of acute leukemias. MPO positive blasts are quite specific for acute myeloid leukemia AML. However PAS block positivity is seen in Acute Lymphoblastic Leukemia ALL, which has significance in absence of MPO positivity Perioral pallor and Dennies line are seen in:Atopic dermatitiChronic actinic dermatitisBlood dyscrasiaPerioral contact dermatitis  <response>: Atopic dermatitis 