Complete hemogram with ESR and peripheral blood smear

Your doctor may order a CBC if you show the following symptoms:

• Weakness
• Fatigue
• Bruising
• Fever
• Weight loss

A CBC can check for the following conditions:

• Anaemia
• Infections
• Blood diseases like leukaemia
• Polycythaemia 

In case of bleeding, this test can also be performed to check how much blood you have lost. 

A CBC can also be performed to check if a certain drug treatment or radiation treatment is effective. Additionally, this test is performed before and after a surgery to check for problems related to RBCs, especially anaemia, and infection. If there is a specific condition, for example, asthma or allergy, your eosinophil levels will be high. 

A CBC may also be performed as part of a routine physical examination.

An ESR checks for various conditions that may cause your ESR to spike. These include inflammatory conditions like rheumatoid arthritis. However, this test cannot diagnose any specific disease or condition. It just indicates that there may be an active disease in the body. 

The following are the symptoms of an inflammatory condition:

• Fever
• Headaches
• Joint stiffness
• Loss of appetite
• Weight loss
• Neck pain or shoulder pain
• Anaemia

A blood smear is done to look for the following:

• Jaundice (yellowing of the eyes and skin)
• Feeling dizzy or tired at all times
• Fever that may persist or recur, especially after travelling to a developing country
• Possibility of malaria
• Low RBC levels

Also, this test can be used to diagnose conditions like sickle-cell anaemia. An important symptom of sickle-cell anaemia is recurring severe, unexplained chest pain. It may also be used to check if a chemotherapy treatment is working.

You do not need any special preparation for this test. Wear a half-sleeved shirt or t-shirt when you go for the test as it will be easier to withdraw a sample of your blood. Tell your doctor if you are consuming any medicines, which includes all the vitamins, herbs, supplements, non-prescription drugs and illegal drugs, as these may affect your test results. 

For the blood smear test, enquire if you can drink and eat before undergoing this test. 

Inform your doctor if you smoke or have had a blood transfusion recently as these can affect the results of CBC. 

Tell your doctor if you are on your period, recently had a fatty meal or are pregnant. These conditions will affect your ESR test results. Old age and obesity can also affect ESR.

This test is done on a blood sample. Your doctor will use a sterile needle to obtain the sample from a vein in your arm and immediately send it to a laboratory for testing. Some of the risks associated with blood tests include bleeding, bruising or infection at the needle insertion site.

Normal results:

Your doctor will evaluate your test results based on factors such as health. It means that even if you have abnormal results, it does not mean you have a health condition. 

Since pregnancy may also affect your CBC test results. Talk to your doctor to know more about the different reference ranges for each trimester. 

CBC

The normal reference values for different parameters measured within CBC are as follows:

• RBC count:

  • Men: 4.5-5.5 million RBCs per microlitre (mcL) or 4.5-5.5 x 1012 per litre (L)
  • Women: 4.0-5.0 million RBCs/mcL or 4.0-5.0 x 1012/L
  • Children: 3.8-6.0 million RBCs/mcL or 3.8-6.0 x 1012/L
  • Newborns: 4.1-6.1 million RBCs/mcL or 4.1-6.1 x 1012/L
• WBC count: 
  • Men and non-pregnant women: 5,000-10,000 WBCs per cubic millimetre (mm3) or 5.0-10.0 x 109 WBCs per litre (L)
• WBC differential:
  • Neutrophils: 50%-62%
  • Eosinophils: 0%-3%
  • Basophils: 0%-1%
  • Monocytes: 3%-7%
  • Lymphocytes: 25%-40%
  • Band neutrophils: 3%-6%
• Hgb:
  • Men: 14-17.4 grams per decilitre (g/dL) or 140-174 grams per litre (g/L)
  • Women: 12-16 g/dL or 120-160 g/L
  • Newborns: 14.5-24.5 g/dL or 145-245 g/L
  • Children: 9.5-20.5 g/dL or 95-205 g/L 
• HCT:
  • Men: 42%-52% or 0.42-0.52 volume fraction
  • Women: 36%-48% or 0.36-0.48 volume fraction
  • Children: 29%-59% or 0.29-0.59 volume fraction 
  • Newborns: 44%-64% or 0.44-0.64 volume fraction
• RBC indices:
  • MCH (adults): 28-34 picograms (pg) per cell
  • MCV (adults): 84-96 femtolitres (fL) 
  • MCHC (adults): 32-36 grams per decilitre (g/dL) 
• RDW:
  • Normal: 11.5%-14.5%
• Platelet count:
  • Adults: 140,000-400,000 platelets/mm3 or 140-400 x 109/L
  • Children: 150,000-450,000 platelets/mm3 or 150-450 x 109/L
• MPV:
  • Adults: 7.4-10.4 cubic micrometre (mcm3) or 7.4-10.4 fL
  • Children: 7.4-10.4 mcm3 or 7.4-10.4 fL

ESR (Westergren method)

The normal values for ESR are as follows:

• Men aged under 50 years: less than 15 millimetres per hour (mm/h)
• Men aged over 50 years: less than 20 mm/h
• Women aged under 50 years: less than 20 mm/h
• Women aged over 50 years: less than 30 mm/h
• Newborns: 0-2 mm/h
• Newborns to puberty: 3-13 mm/h

Peripheral Smear (P/S)

The P/S results are considered normal in the following conditions:

• Normal appearance of cells
• Normal WBC differential

These normal values are just a reference range and should be used as a guide. The values differ between different laboratories, and your laboratory report will have the reference range they use. 

Abnormal results:

Indications for different test results if the values are higher than the normal are as follows:

• RBC count: 

  • Smoking
  • Dehydration
  • Diarrhoea or vomiting
  • Some cancers
  • Certain heart diseases
  • Exposure to carbon monoxide
  • Excessive sweating
  • Use of diuretics
  • Kidney disease
  • Long-term lung disease
  • Liver disease
  • Alcohol use disorder
  • A rare disorder of the bone marrow (polycythaemia vera)
  • A rare disorder of Hgb that binds oxygen tightly.
  • Spurious polycythaemia (the lack of fluid in the body makes the RBC volume look high)
• WBC count: 
  • Inflammation
  • Infection
  • Severe physical or emotional stress, for example, injury, fever or surgery
  • Use of corticosteroids
  • Use of certain medicines
  • Malnutrition
  • Thyroid gland problems
  • Removal of the spleen
  • Tuberculosis 
  • Damage to body tissues, for example, heart attack
  • Kidney failure
  • Lupus
  • Leukaemia
  • Rheumatoid arthritis
  • Underactive adrenal glands
• Platelet count:
  • Iron deficiency 
  • Bleeding
  • Bone marrow conditions
  • Cancer

Indications for different test results if the values are low are as follows:

• RBC count:

  • Anaemia, which may be due to stomach ulcers, heavy menstrual bleeding, colon cancer, sickle-cell disease, lead poisoning, thalassaemia, vitamin B12 deficiency and so on.

Blood smear can help in diagnosing the cause for anaemia. 

• WBC count:

  • Reaction to other medicines
  • Viral infections
  • Alcoholism
  • Malaria
  • Lupus
  • Aplastic anaemia
  • Enlarged spleen
  • Chemotherapy
  • AIDS
• Platelet count:
  • Pregnancy
  • Conditions such as immune thrombocytopenic purpura or others that affect the way platelets are produced and destroy the platelets
  • Large spleen

An ESR can help in diagnosis, but it does not give a confirmed result that indicates a specific condition. An abnormally high ESR indicates the following:

• Anaemia
• Pregnancy
• Kidney disease
• Thyroid disease
• Autoimmune conditions:
  • Rheumatoid arthritis
  • Lupus
  • Allergic vasculitis
  • Macroglobulinaemia (primary)
  • Necrotising vasculitis
  • Giant cell arteritis
  • Hyperfibrinogenaemia (increased fibrinogen levels)
• Infections:
  • Bone infections
  • Rheumatic fever
  • Body-wide (systemic) infection
  • Severe skin infections, such as erysipelas
  • Tuberculosis
  • Infection of the heart or heart valves

Cancers such as lymphoma or multiple myeloma

If you have ESR values below normal, it may indicate the following:

• Hypofibrinogenaemia (decreased fibrinogen levels)
• Polycythaemia
• Congestive heart failure
• Leukaemia
• Low plasma protein due to kidney or liver disease
• Sickle-cell anaemia

If your P/S results are abnormal, it could be graded as follows:

• 1+ means one-quarter of cells are affected
• 2+ means one-half of cells are affected
• 3+ means three-quarters of cells are affected
• 4+ means all the cells are affected

If cells known as target cells are observed, it can indicate the following:

• Iron deficiency
• Liver disease
• Spleen removal
• Deficiency of an enzyme, lecithin–cholesterol acyltransferase
• Abnormal Hgb 

If sphere-shaped cells are noticed, it can indicate the following:

• Increased breakdown of RBCs
• Immune haemolytic anaemia: a low number of RBCs due to the body destroying them 
• Hereditary spherocytosis: a low number of RBCs due to some RBCs that are of a sphere-like shape

The presence of oval-shaped RBCs may indicate hereditary elliptocytosis or hereditary ovalocytosis. 

If fragmented cells are noticed, it may indicate the following:

• Disseminated intravascular coagulation: A disorder in which the proteins that control blood clotting become overactive
• Artificial heart valve
• Haemolytic uraemic syndrome: An infection in the digestive system producing toxic substances that destroy RBCs
• Thrombotic thrombocytopenic purpura: A disorder with low platelet count and formation of blood clots in small blood vessels

The presence of a type of immature RBCs, called normoblasts, may be due to the following:

• Thalassaemia: A disorder in which there is excessive breakdown of hemoglobin 
• Miliary tuberculosis: a type of tuberculosis that has spread from the lungs to other parts of the body through the blood 
• Myelofibrosis: A disorder of the bone marrow in which the marrow is replaced by fibrous scar tissue 
• Haemolysis: Severe breakdown of RBCs
• Removal of spleen
• Erythroblastosis fetalis: A blood disorder affecting a foetus or newborn
• Cancer that has spread to bone marrow

If Heinz bodies (bits of altered Hgb) are noticed, it may be due to the following:

• Congenital haemolytic anaemia
• Unstable form of Hgb
• Alpha thalassaemia
• G6PD deficiency: A disorder in which RBCs break down on exposure to certain drugs or are stressed because of infection 

If the cells called burr cells (a type of abnormal RBCs) are observed, it may indicate the following:

• Uraemia: Abnormally high level of nitrogen waste products in the blood

If teardrop-shaped red blood cells are observed, it may indicate the following:

• Severe iron deficiency
• Thalassaemia major
• Cancer in the bone marrow
• Anaemia caused by bone marrow not producing normal blood cells due to toxins or tumour cells (myelophthisic process) 

If slightly immature RBCs are noticed, it may indicate the following:

• Anaemia with bone marrow recovery
• Haemorrhage
• Haemolytic anaemia

If Howell–Jolly bodies (a type of granules) are observed in RBCs, it may be due to the following:

• Spleen has been removed
• Sickle-cell anaemia
• Myelodysplasia (a condition where the bone marrow does not produce sufficient healthy blood cells)

If the cells called spur cells (larger than normal RBCs that have spikes) are observed, it may indicate the following:

• Severe liver disease
• Abetalipoproteinaemia: inability to completely absorb dietary fats through the intestines

If the basophils have a spotted appearance (basophilic stippling), it may be due to the following:

• Myelofibrosis
• Lead poisoning

The presence of sickle-shaped red blood cells may indicate sickle-cell anaemia.

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. The above information is provided from a purely educational point of view and is in no way a substitute for medical advice by a qualified doctor.