Unit 2-Question 2: A.If the neutrophil count was high in
a WBC differential, what kind of infection would you
suspect?  B.If the lymphocyte count was high?

Answers: A.Neutrophils are the first responders in the
inflammatory response process, arriving to the site of
injury within the first 6-12 hours (McCance & Huether,
2006). A high neutrophil count is usually indicative of
a bacterial infection in its early phase (McCance &
Huether). The “primary roles of the neutrophils are
removal of debris in sterile lesions, such as burns, and
phagocytosis of bacteria in non-sterile lesions”
(McCance & Huether, p. 194). For example, if a patient
with pneumonia develops a fever after several days of
antibiotic therapy, a new CBC/Diff is obtained. If the
neutrophils are elevated, a new infectious organism is
suspected, and it is advisable that new blood cultures
are drawn to assess for appropriate antibiotic coverage
for the probable new bacteria.

B.Lymphocytes are present in all infections, arriving
later in the inflammatory response process;
approximately 24 hours after the onset of injury,
lymphocytes replace the neutrophils (McCance & Heuther,
2006). A high lymphocyte count is usually indicative of
a viral infection (McCance & Heuther). However, chronic
inflammation is also “characterized by a dense
infiltration of lymphocytes” (McCance & Heuther, p.
200), even though this inflammation may not be of viral
origin.  

References 

McCance, K.L., & Huether, S. E. (2006).
Pathophysiology: The biologic basis for disease in
adults and children. Elsevier  Mosby: St. Louis.