How do i know if i has alopecia areata.and what labotary texts should i have to done to check wheather i have alopecia.?

Areas of hair loss: This is a descriptive term--hair loss in discrete areas, and no blood test can detect hair loss. Certain condition may result in hair loss but a blood test cannot tell specifically, especially in areata. This is a physical diagnosis--just by looking at it. Often, no cause is found for this and usually hair regrowth occurs in a few months without any treatment. Consult doc. Good luck.