Interpretation of leukocyte responses in disease Flashcards
Leukemia is
neoplastic cells in the blood and/or bone marrow
Leukemoid response or reaction is
can easily be mistaken for leukemia
Leukemoid response or reaction is characterized by
Marked leukocytosis (>50.0 x 10⁹WBC/L)
Usually due to an inflammatory response
Pancytopenia means
refers to a decrease in the number of all blood cell types
Left shift means
increased numbers of immature neutrophils in the blood
Degenerative left shift means
normal to decreased numbers of mature neutrophils with equal or higher numbers of immature neutrophils BAD
Leukopenia looks like
A decrease in white blood cell numbers
Leukopenia may be balanced with a decrease in the number of all cellular elements, or it may be confined to one cellular element
Nursing care and great nutrition are important to prevent secondary infections & for bone marrow function
Common causes of leukopenia
Viral infections
Overwhelming bacterial infections
Anaphylactic shock & endotoxic shock
Certain antibiotics
Chemotherapeutic drugs
Some analgesics
Lead, mercury, antihistamines, & cortisone products
A cachectic state (usually due to anorexia)
Leukocytosis looks like and is due to
An increase in white blood cells
Usually due to a rise in the number of circulating neutrophils
Commonly occurs due to a physiological cause (as opposed to a pathological one)
Physiological causes of leukocytosis
EXERCISE (more common in cats & horses)
STRESS (more common in dogs)
TRAUMA
STEROID THERAPY
CHRONIC ILLNESS
Due to an increase in other cell types
Stress response results in WBC
WBC changes that occur in response to stress, chronic illness, exercise or steroid supplementation
The absence of a stress response in an animal that is sick is significant
What will you see in a cat and dogs blood smear from a stress response
you will see a mature neutrophilia, monocytosis, lymphopenia, possible eosinopenia
What will you see in a cattles blood smear from a stress response
reversal of neutrophil to lymphocyte ratio even if both are still within reference limits
What will you see in a horses blood smear from a stress response
mature neutrophilia and lymphopenia*
Pathological Causes of Leukocytosis
Systemic or localized infections–can cause marked neutrophilia (in dogs also monocytosis) with a possible left shift
Mastitis, peritonitis & metritis
Inflammation
Acute hemorrhage –especially if it is into a body cavityt
Sudden lyses of erythrocytest
Some toxinst
Neoplasia
Leukemia– may produce an increase in bizarre, atypical cell types and a severe left shift
t These cases usually result in a neutrophilia with NO left shift, may be followed by a monocytosis
Leukocytosis is and related to
The total leukocyte response in an individual is directly related to the patient’s susceptibility to an infection, it’s immune status, and it’s general health
Debilitated animals may fail to show the expected response
The bone marrow may be affected by the underlying condition
Left shift refers to
Refers to an increased concentration of immature neutrophils in the peripheral blood
Band neutrophils are the first immature cells to appear
Metamyelocytes or earlier immature forms may also be seen
Can accompany either a neutrophilia or neutropenia
What does a left shift look like
Orderly classification-there should be fewer immature cells than mature neutrophils
Left shifts are described as
Left shifts are usually described as to the degree of the shift
They are termed slight or mild if shifted to the band neutrophil stage
Moderate if shifted to the metamyelocyte stage
Marked or severe if shifted to the myelocyte or promyelocyte stage
Regenerative Left Shift looks like
A leukocytosis due to a neutrophilia & the appearance of immature neutrophils that do not out-number the mature neutrophils → the bone marrow is responding to the inflammatory stimulus
Degenerative Left Shift looks like
The total WBC count is often normal, but it can also be above or below the normal range
The immature neutrophils out-number the mature ones → the bone marrow is no longer keeping up to the demands of the body
Usually indicates a poor prognosis
A DEGENERATIVE left shift accompanying a low total WBC count calls for a guarded prognosis
Regenerative to a Degenerative Left Shift
It will take some time to go from a regenerative to a degenerative shift
At first the body will be able to maintain a leukocytosis
In time, the total WBC count will fall & a leukopenia develops
What happens to the bone marrow with a left shift
The bone marrow’s ability to respond is measured by the total leukocyte count
The intensity of the response is measured by the extent of the left shift
Leukemoid Response/Reaction
This is a condition that is easily mistaken for a leukemia
The leukemoid response & leukemia can only be differentiated via a bone marrow exam
With both conditions, the peripheral blood shows an increased total count with a severe left shift
A leukemoid response is usually associated with severe inflammation & infection such as a pyometra, hepatic abscesses, etc
A leukemoid response is likely treatable while leukemia has a grave prognosis
