White Blood Cell Differential Count
DR. Yasir M. Khaleel M.B.Ch.B , M.Sc.Definition
The relative percentage of each type of white blood cells in peripheral blood.White Blood Cells (leucocytes) Total 4.0 – 11.0 Ч 10 9 /LAbsolute Relative Percentage AverageNeutrophils 2.5 – 7.5 Ч 10 9 /L 50-70% 65%Lymphocytes 1.5 – 3.5 Ч 10 9 /L 25-35% 30%Monocytes 0.2 – 0.8 Ч 10 9 /L 2-10% 6%Eosinophils 0.04 – 0.44 Ч 10 9 /L 1-5% 3%Basophils 0.01 – 0.1 Ч 10 9 /L 0.4-1% 0.5%
Microscopic exam
tail body headCounting Area:
Observe one field and record the number of WBC according to the different type then turn to another field in the snake-liked direction *avoid repeat or miss some cellsNormal peripheral blood smear
White blood cells
There are three types of granulocyte named according to their staining characteristics in blood films. They are neutrophils,eosinophils and basophils. Mononuclear cells are divided into lymphocytes and monocytes.Stab (band) neutrophil
Diameter:12-16 Cytoplasm : pink Granules : primary & secondary Nucleus : dark purple blue dense chromatinBand form Neutrophils
There are smaller numbers of cells of neutrophil lineage with non-segmented nuclei. They are referred to as neutrophil band cells or band forms. They are less mature than segmented neutrophils. An increased number of band cells is referred to as a left shift'.Segmented neutrophil
Diameter: 12-16 Cytoplasm: very pale blue Granules: primary secondary lilac-staining (purple) Nucleus: dark purple blue dense heterogeneous chromatin 2-5 lobesNeutrophils
The neutrophils in the circulating blood are mainly mature segmented neutrophils. neutrophilic because they owe their color to uptake of both the acidic and the basic components of the stainEosinophil
Diameter: 14-16 Cytoplasm : full of granules Granules: large refractile orange-red Nucleus: blue dense chromatin 2 lobes like a pair of glassBasophil
Diameter: 14-16Cytoplasm: pinkGranules: dark blue –black obscure nucleusNucleus: blue
Lymphocyte
Diameter: small 7-9 large 12-16 Cytoplasm : rim, clear, pale blue Granules: small (a granular) large (a variable number of pinkish-purple granules) Nucleus: dark blue / round dense homogeneous chromatinNormal lymphocytes
Lymphocytes are the smallest WBC. They have large condensed nucleus, with a scanty pale blue cytoplasm.Monocyte
Diameter: 14-20(are the largest normal blood cells) Cytoplasm: grey blue Granules: dust-like lilac color granules(purple) Nucleus: blue large irregularly shaped and foldedThe red blood cells here are normal, happy RBC's. They have a zone of central pallor about 1/3 the size of the RBC. The RBC's demonstrate minimal variation in size (anisocytosis) and shape (poikilocytosis). A few small fuzzy blue platelets are seen. In the center of the field are a band neutrophil on the left and a segmented neutrophil on the right.
Samples of Blood films: 1
A normal mature lymphocyte is seen on the left compared to a segmented PMN on the right. An RBC is seen to be about 2/3 the size of a normal lymphocyte
Samples of Blood films: 2
Here is a monocyte. It is slightly larger than a lymphocyte and has a folded nucleus. Monocytes can migrate out of the bloodstream and become tissue macrophages under the influence of cytokines. Note the many small smudgy blue platelets between the RBC's.
Samples of Blood films: 3
In the center of the field is an eosinophil with a bilobed nucleus and numerous reddish granules in the cytoplasm. Just underneath it is a small lymphocyte. Eosinophils can increase with allergic reactions and with parasitic infestations.
Samples of Blood films: 4
There is a basophil in the center of the field which has a lobed nucleus (like PMN's) and numerous coarse, dark blue granules in the cytoplasm. They are infrequent in a normal peripheral blood smear, and their significance is uncertain. A band neutrophil is seen on the left, and a large, activated lymphocyte on the right.
Samples of Blood films: 5
Terms
Leucocytosis Vs Leucopenia k/c Neutrophilia Vs Neutropenia Lymphocytosis Vs Lymphocytopenia Monocytosis Vs Monocytopenia Eosinophilia Basophilia Granulocytosis AgranulocytosisErythrocytes Sedimentation Rate ESR
DR. Yasir M. Khaleel M.B.Ch.B , M.Sc.ESR
Erythrocyte Sedimentation Rate: Def: The distance that erythrocytes have fallen after 1 hour in a vertical column of anti-coagulated blood under the influence of gravity. The most satisfactory method was provided by Westergren 1921
ESR is a non-specific test for inflammation. It is easy to perform, widely available and inexpensive making it a widely used screening test Normal ESR not exclude disease High ESR not confirm the disease unless proved by other tests. It is also used a monitoring test for response to treatment in conditions in which it is raised (tuberculosis, autoimmune diseases etc(
Basics: The ESR test is performed in the laboratory by placing anti-coagulated blood in an upright tube (Westegren's most often). At the end of an hour of this, the rate of the RBC sedimentation is measured
Factors affecting the ESR
A- Plasma related factors: Increased in the concentration of fibrinogen and Immunoglobulins due to inflammation and tissue injury will increase rouleaux formation and hence the rate of sedimentation. Plasma proteins especially fibrinogen, adhere to the red cell membranes and neutralize the surface negative charges, promoting cell adherence and rouleaux formation. Any condition associated with increase in plasma fibrinogen will lead to elevated ESR ( infection, inflammation, malignancy) Plasma albumin retards sedimentation of RBCs.The RBC's here have stacked together in long chains. This is known as "rouleaux formation" and it happens with increased serum proteins, particularly fibrinogen and globulins. Such long chains of RBC's sediment more readily. This is the mechanism for the sedimentation rate, which increases non-specifically with inflammation and increased "acute phase" serum proteins.
B-The RBC related factors:1-The size or mass of the RBC: macrocytes have faster rate of fall so read higher ESR with macrocytic anaemia. 2- Shape of RBCs that show alterations in their bioconcavity, like spherocytes and sickle cells (these RBCs can’t form rouleaux), usually do not exhibit increase rate, unless there is severe anemia. 3- RBC count :Increase red cell mass will retard the sedimentation rate e.g. polycythemia, Vs anaemia
Reference Range
Adults < 50 years: Females 0-20 mm/hr ; Males 0-15 mm/hr Adults > 50 years: Females 0-30 mm/hr ; Males 0-20 mm/hr For older ages (Females : (Age +10)/2; Males: Age/2) Children(<10) 0-10 mm/hrPhysiological variations
Sex: females have higher ESR than males. Age: old age specially after 60 have higher ESR. Children have lower ESR reading. Pregnancy and Menstruation: higher ESR Weight: Obesity: slightly higher ESR reading. Drugs: Aspirin and other NSAIDs, and cortisone may be associated with slightly lower ESR reading, while OCP, vitamin A and theophylline are associated with high ESR reading Recent meal before the test (might) be associated with slightly high ESR reading.Slightly Elevated ESR, simply repeat the test after 1-2 months.ESR ≥100 mm/hr is strongly associated with serious underlying disorders like:* Connective tissue disease, * Infections ( specially chronic infections like TB)* Malignancies Clinical Evaluation of High ESR Reading
ESR is helpful in diagnosing two specific inflammatory diseases, temporal arteritis and polymyalgia rheumatica.
Some conditions with very high ESR >100 mm/hr
- Multiple myeloma - Connective tissue disorders - SLE, RA and other autoimmune diseases - Tuberculosis - Malignancies - Severe anemia