Final answer:
An increased count of polymorphonuclear cells in a leukocyte differential smear with a high leukocyte count may indicate an acute infection, inflammation or a condition like leukemia.
Step-by-step explanation:
When a leukocyte differential smear made from a specimen with an elevated leukocyte count reveals an increase in polymorphonuclear cells, it may indicate an acute infection or inflammation. Polymorphonuclear leukocytes, also known as neutrophils, are a type of white blood cell that play a crucial role in the immune system by responding quickly to infections. An increase in these cells can be seen in conditions like bacterial infections and is part of leukocytosis, which is the excessive proliferation of leukocytes. However, such a differential can also indicate other conditions such as leukemia, a type of cancer that affects the blood and bone marrow.