一般 >10% eosinophils就要做manual differential 的, 所以假定形態應該正常的。。。
http://www.medicalnewstoday.com/articles/311601.php
Low levels of eosinophils
Because normal levels of eosinophils can be 0, a low level of eosinophils isn't usually considered a medical problem after one test.
However, there are some conditions that can cause a low level of eosinophils, which is known as eosinopenia. This includes drunkenness and medical conditions that cause the body to produce too many steroids.
An example is an overproduction of cortisol, which can restrain the immune system.
cortisol 也降淋巴細胞的呀。