Are neutrophilia and neutropenia the same disease?

No: They're the opposite: neutropenia is a low number of neutrophils, a type of infection-fighting white blood cell. Neutophlia is a high number of neutrophils (also referred to as neutrophilic leukocytosis). Neither is a disease. These are just descriptive terms for laboratory abnormalities.

Neutropenia is....: Defined as an absolute neutrophil count (anc) less than 1500. From there it is subdivided into mild (1000-1500), moderate (500-1000) and severe (<500). Folks with severe neutropenia are at increased risk for bacterial infections. Neutrophilia means the opposite (more than the normal number). It is commonly found when fighting off bacterial infection. A "left shift" is relative rise in neutrophils.