why absolute lymphocytosis in pertusis instead of neutrophil elevation since it is bacterial infection
In pertussis, absolute lymphocytosis (elevation of lymphocytes in the blood) occurs because the causative agent Bordetella pertussis primarily targets and infects lymphocytes in the respiratory tract. This results in a proliferation of lymphocytes in response to the infection, leading to their increase in the bloodstream.
On the other hand, neutrophils are the first responders to bacterial infections in the body and are typically elevated in response to bacterial infections. However, in pertussis, the immune response is characterized by a significant increase in lymphocytes rather than neutrophils. This is a unique characteristic of pertussis infection and is why absolute lymphocytosis is seen instead of neutrophil elevation.