A differential blood count is a blood test to check your white blood cell levels, which can indicate the presence of infection, disease, or an allergic reaction. Your doctor might order it as part of ...

FIGURE 1. Platelet clumping (blue) was seen on peripheral blood smear. A misdiagnosis would have led to unnecessary tests and treatment. Ms. J, age 55 years, was referred to hematology for evaluation ...

DEAR MAYO CLINIC: I am 33 years old and recently had an annual physical and routine blood work. I'm active with two children and feel fantastic, but my platelet count came back as 651. My health care ...