ABSOLUTE EOSINOPHIL COUNT

Decreased eosinophil numbers

EOSINOPENIA are associated with HYPERADRENALISM (Cushing disease)

what does the chromatin look like in eosinophils

clumped

eosinophils have a _____ core in their granules

crystalloid core

eosinophils granules are large/smaller than neutrophilic granules

larger

the crystalloid core in the granules of eosinophils consists of ____

major basic protein

major basic protein is toxic to _____

parasites

what color are eosinophil granules

pink, red, orange

the solid crystal of the crystalloid core is like a ____ that when hit by light and administered in a million different directions

prism

the crystalloid core of the granules of an eosinophil is a ____ crystal

solid

the granules of an eosinophil are located closer to the ___ when compared to neutrophils

surface

eosinophils are extremely ____

toxic

Several Factors influence the number of eosinophils in circulation:

- Bone marrow proliferation and release into the blood stream, movement from the blood into extravascular tissues, and cell survival and destruction after eosinophils have moved into the tissues.

Eosinophilia

- Defined as an absolute eosinophil count greater than 0.4x10^9/L. - A major function of eosinophils is degranulatation , where substance are released that damaged an offending organism (parasite) or target cell.

Eosinophil accumulation in the gastrointestinal tract occurs in allergic disorders such as:

- Food allergy - Allergy - Allergic colitis - Inflammatory bowel disease such as: Crohn's disease and ulcerative colitis

Secondary granules:

- Formed throughout remaining maturation Contain: - Major basic protein (core) - Eosinophils cationic protein (matrix) - Eosinophil derived neurotoxin (matrix) - Lysozyme (matrix) - Catalase (core and matrix) - Cathepsin D (core and matrix) - Interleukin 2, 4, 5 (core) - Interleukin 6 (matrix) - Granulocyte macrophage colony stimulating factor (core)

Eosinophils granules are:

- Full of of a large number of previously synthesized proteins, including: * Cytokines * Chemokines * Growth factors * Cationic proteins

Function of cortisol in eosinophil:

- Ga induce sa migration of eosinophil - Ga decrease siya sang eosinophils

Treatment with anti-IL5 monoclonal antibody

- Has been found to reduce exacerbation in certain asthmatic patients.

EOSINOPHILS

- Have also been implicated in airway remodeling (increase in thickness of the airway wall) through eosinophil derived fibrinogenic growth factors, especially in STEROID RESISTANT ASTHMA.

2 Methods:

- Indirect (WBC count x percent of eosinophil in the diff count) - Direct method (most wide used procedure) = Double check using indirect

Two general methods for determining the absolute eosinophil count:

- Indirect method = White blood cell count multiplied by the percentage of eosinophil in the differential - Direct method = The most widely used procedure is to perform the eosinophil count by the direct method and double check these results using the Indirect method.

Purpose of cortisol in eosinophil

- Induces migration of eosinophil - Ga decrease siya sang eosinophils

Eosinopenia

- Is defined as an absolute eosinophil count of less than 0.09x10^9/L and can be difficult to detect because the reference interval is low. - Eosinopenia often accompanies other cytopenias in conditions that result in marrow hypoplasia, specifically involving leukocytes. - Eosinopenia has been reported in: *Autoimmune disorders *Steroid therapy, *Stress, *Sepsis and *Acute inflammatory states.

Eosinophil production

- Is increased in infection by PARASITIC HELMINTH, and in vitro studies have found that the eosinophil is capable of destroying tissue invading helminths through the secretion of MBP and eosinophil cationic protein as well as the production of reactive oxygen species.

An Absolute eosinophil count

- Is still requested for diagnostic purposes because it may be more accurate and clinically meaningful to determine the absolute number of eosinophil in a volume of blood than to determine the relative number from the differential count.

Volume of the area counted is 1.8

- It has 2 ruled section - Each section has an area of 9 sq.mm and a depth of 0.1mm, therefore, the volume of 1 section is 9x0.1 = 0.9 cubic mm & the volume of 2 section is 2 x 0.9

The relative and absolute number of eosinophil in the blood

- May be determined from the WBC and differential white cell count. - It is more accurately determine the total number of eosinophils per liter of blood. - The direct method for counting eosinophils is similar to the method used for the red and white cell counts.

Reagents:

- Phloxine (Stain) = Causes eosinophil to turn red - Propylene glycol = Lyse rbc (Diluting fluid) - Heparin = Inhibit leukocyte clumping = Lyse wbc - Sodium Carbonate = Enhances eosinophil (granules) staining PURPOSE: Detects allergic diseases - Infections

FUNCTIONS:

- Provides protection against allergies and parasites Allergies: Asthma, Hay fever

Why would someone choose to do an Eosinophil count?

-more accurate than differential -allergy monitoring

Eosinopenia: If the count is less than 40/uL is called EOSINOPENIA

Condtions: - Hyperadrenalism (Cushing disease) - Shock - Administration of Adrenocoticosteroids (ACTH)

Increased eosinophil numbers

EOSINOPHILIA associated with: - Allergic reactions - Parasitic infestations - Brucellosis and - Certain leukemias. - There may be considerable diurnal fluctuation in the eosinophil count over 24 hour period. - With the lowest generally present during late morning and the highest count present at midnight.

Hypogranular eosinophils

- Have been associated with acute lymphoblastic leukemia and hypereosinophilic syndrome. - In vitro disruption of the cellular membrane may occur during the process of making the blood film as eosinophils are fragile. To promote accuracy, it is recommended that fractured eosinohphils be counted as eosinophils in the manual WBC differential.

Diurnal Fluctuation of eosinophil

- Hormonal influences - Presence of illness

Eosinophil play

A role in preventing reinfection.

DECREASED EOSINOPHIL COUNT (EOSINOPENIA)

- Acute stress - Steroids (taking drugs) - Acute pyogenic infection (neutrophil increased so decrease eosinophil) - Hyperadrenalism (Cushing 's disease)

INCREASED EOSINOPHIL COUNT (EOSINOPHILIA)

- Allergic reaction (Skin allergy, asthma, hay fever) - Parasitic infection - Brucellosis - Certain leukemias (Lymphoma) - Lupus (Autoimmune disease)

Non malignant causes of eosinophilia

- Are generally a result of cytokine stimulation, especially from interleukin 3 and interleukin 5.

Primary granules:

- Formed during promyelocyte stage

Eosinophilia

- A hallmark of allergic disorders, of with asthma has been the best studied.

What is the relative eosinophil count?

% of Eos in peripheral blood

Normal Values

*30-35 u/L *% = 1-3 *0 divided by 0.3 x 10^9/L *21 years old = 0-0.45x10^9/L

PROCEDURE

1. Make a 1:10 dilution by drawing well mixed blood to the 1.0 mark of WBC pipet and adding eosinophil stain diluents to 11 mark. 2. Make a duplicate dilution. Mix both pipets for approximately 2 minutes. 3. Expel first four drops of mixture onto waste cloth and fill one side of counting chamber. (gina expel siya kay tungod sa unmixed) 4. Repeat the procedure using the other pipet for the opposite side of the chamber. 5. Place filled counting chamber into moist Petri dish. Allow 15 to 20 minutes for cells to settle, red cells to lyse, and eosinophils to stain. (para ma avoid of lysing of eosinophil and e avoid ang chamber from drying up) - If the mixture overflows into the moat or air bubbles occurs, clean and dry the chambers, remix the contents of the pipet, and refill both chambers 6. Count eosinophils under low power (10x) objective. Count the entire ruled area (9 large squares) on both sides of counting chamber. Eosinophils stain reddish orange. - Recharge the chamber if distribution is not uniform 7. Calculate the number of eosinophils/mm3 as - number of eosinophils x dilution factor over the area volume counted - Number of cell counted x dilution over area counted *dilution = 10 *Area counted = 9 *Depth = 1.8 cubic mm§§

on a WBC differential eosinophils will be ____ if a patient has allergies

10-15%

what is the size of an eosinophil

10-15um

on a WBC differential eosinophils will be ____ if the patient has a parasitic infection

45-50%

Normal Range for Eosinophil Count

50-400 Eos/uL

how longs does an eosinophil survive in the tissues

6 days

Reasons for increased Eosinophil Counts

Allergic reaction, tuberculosis, asthma, parasite, NOT Inflammation

What is the stain used in total eosinophil counts?

Pilot's Stain

Name of diluting fluid:

Pilot's diluting fluid

Eosinophilia: If the absolute eosinophil count is more than 440/uL it is called EOSINOPHILIA

Some conditions in which eosinophilia is seen: - Allergic reaction - Parasitic infections - Brucellosis is a bacterial infection that spreads from animals to people. - Certain leukemias

PRINCIPLE:

Using a suitably diluted specimen and appropriate stain, eosinophil can be identified and counted microscopically, after specimen is loaded on a HEMOCYTOMETER. PHLOXINE in the stain causes eosinophil to appear RED under light microscopy. RED BLOOD CELLS are lysed by PROPYLENE GLYCOL in the diluting fluid. The SODIUM CARBONATE and WATER help to laze the white blood cells (except eosinophils). HERAPIN, if present in the diluting fluid, inhibits leukocyte clumping. SODIUM CARBONATE also enhances the staining of eosinophil granules. - The count is reported in terms of cell per liter.

eosinophils increase during ____ and presence of _____ infections

allergies; parasitic

after maturation in the bone marrow, an eosinophils is stored for several days before being released into the ____

blood and migration into the tissues