High White Blood Cell Count In The Elderly 

Overview

Leukocytosis or an Elevated White blood cell (WBC) count can be routinely found on laboratory testing, and it shows the normal response of the bone marrow to multiple internal stimuli. A high WBC count could mean many things from simple body response to allergies or mild infection, stress or trauma to rarer serious and worrisome abnormalities such as cancer or bone marrow disorder.

With ageing there are multiple changes seen in the body at the cellular level. These range from a decreased cell survival time decreased production of new cells or production of abnormal or mutated cells. These changes however are not normally seen in the WBCs of a healthy adult going through ageing. Ageing also does not have any effect on normal WBC count in the blood. It stays the same as in an average healthy young adult. Hence any changes such as a decrease or an increase in the number of WBCs above the age of 60 warrant further assessment. 

Introduction

What are white blood cells?

White blood cells are an important part of the body's defence system. They are responsible for resisting and fighting infection as well as creating long term immunity. They also protect the body from foreign substances.

What are the types of white blood cells?

 The different types of WBCs are:

Granulocytes

These are the types of White blood cells that when seen under the microscope show numerous small particles. There are three types of granulocytes

1. Neutrophils
2. Eosinophils
3. Basophils

Agranulocytes

These are the white blood cells that do not show numerous small particles under a microscope.

There are two kinds of agranulocytes

1. Monocytes 
2. Lymphocytes

The lymphocytes are further of two types the B lymphocytes and the T lymphocytes.¹

How are the white blood cells formed?

The soft tissue of the bones called the bone marrow contains a common ancestor cells “the stem cells”. It can undergo multiple cycles of division and maturation to form all the cellular components of blood including the Red Blood Cells, the White Blood Cells and the Platelets.

The stem cells produce the cell lines of myeloblasts and lymphoblasts. The myeloblasts further differentiate into the monocytes and the granulocytes i.e the neutrophils, basophils and eosinophils. The lymphoblasts develop into T and B lymphocytes in the lymphatic system. Once these WBCs are matured the majority, about 80-90% are stored in the bone marrow while only 2-3% circulate in the blood. The remaining WBCs are deposited along the walls of the blood vessels and spleen. This bone marrow storage of WBCs allows for a rapid release of WBC within hours in the event of an infection or inflammation.²

What is the function of white blood cells?

Different white blood cells have different functions but they are all involved in the immune response of the body to illness and injury.

• Neutrophils: These cells are the first line of defence against bacterial infections and foreign substances.
• Basophils. These cells are responsible for allergic reactions.
• Eosinophils: They are involved in the body’s response to parasitic infections and also work with basophils in allergic reactions.
• Lymphocytes: The lymphocytes protect against viral infections and produce special proteins called antibodies that fight and protect from future infections.
• Monocytes: These cells are responsible for cleaning up damaged and dead cells.

The relationship between white blood cells and the elderly 

With increasing age there is an increased likelihood of long-term illnesses and increased use of medication. These factors can contribute to a deviated WBC count from the normal reference range on testing.

Testing for WBC in the elderly:

1. Done routinely to get an overview of general health.
2. Used as a marker for detecting and assessing the severity of inflammation in the body.
3. It can be used as a strong predictor of mortality in older populations.
4. It is also used to predict the outcome of a cardiovascular event such as heart attack.³

Normal WBC count

The normal white blood cell count ranges between 4,000 and 11,000 cells per microliter (4 to 11 × 10⁹ per liter) in an adult.[6] This reference range remains the same and has no relation to gender or age. ⁴

WBC count is highest in a healthy newborn. It starts decreasing throughout childhood till it reaches the adult level at the age of 21. After that, it remains constant throughout the person's life changing only in response to disease or injury. ⁵

This is in contrast to the Red Blood Cells (RBCs) and Platelets, also present in the blood. Their count decreases with ageing and the normal reference range is also different for different genders.

Abnormal WBC count

A low white blood cell count

A WBC count of less than 4,000 cells per microliter of blood (4 × 109 per liter) is considered to be a low WBC count. This condition is referred to as Leukopenia. Having a low WBC can lower a person’s immunity and make them more susceptible to infection.

Causes of Low WBC count are:

1. Hereditary or genetic conditions
2. Infections such as tuberculosis and HIV and hepatitis
3. Treatments for cancer such as chemotherapy and radiotherapy.
4. Immunosuppressive drugs that suppress the immune system and hence WBCs.
5. Autoimmune diseases such as rheumatoid arthritis
6. Vitamin deficiencies 
7. Liver disease and spleen enlargement
8. Certain cancers like leukaemia.
9.  Bone marrow abnormality (aplastic anaemia)

A high white blood cell count

A White blood cell count of more than 11,000 cells per microliter of blood (11 × 10⁹ per litre) is considered a high WBC count. This condition is termed as Leukocytosis. This can be either due to the appropriate response of a healthy bone marrow to infection or inflammation or it can be a result of an abnormality in the bone marrow.

Causes of a high white blood cell count in elderly on the basis of bone marrow

Normally functioning bone marrow

In most instances a rise in the WBC count in the blood is a result of a normal bone marrow responding to infection or injury. This is an appropriate response and helps the body recover and return to a homeostasis condition.

Some causes include:

1. Infection
2. Physical stress such as over exertion, surgery, trauma
3. Medication side effects such as lithium, anaesthesia, and bronchodilators used in asthma
4. Chronic conditions such as asthma 
5. Autoimmune conditions such as rheumatoid arthritis, Crohn's disease
6. After surgical removal of spleen
7. Emotional stress, and anxiety

Abnormally functioning bone marrow:

 These conditions are relatively rare but occur when the bone marrow produces abnormal cells. Some examples in the elderly include:

1. Chronic lymphocytic leukaemia
2. Myeloproliferative disorders

Cause of high white blood cell count on basis of cell type

Neutrophilia:

Neutrophilia occurs when there is a rise in the number of neutrophils in the blood. This is the most common type of leukocytosis.

This can occur in:

1. Bacterial infections
2. Injuries such as hip fracture
3. Certain drugs such as corticosteroids
4. Autoimmune disorders such as Rheumatoid arthritis

Eosinophilia

This is a rise of eosinophils in the blood.

This can occur in:

1. Allergic reactions
2. Parasitic infections
3. Conditions such as asthma
4. Hypereosinophilic syndrome. This is a rare condition that does not have any obvious cause and can affect people over the age of 50. In this condition, eosinophilic cells damage the heart, lungs, liver and nervous system.

Basophilia

An increase in the number of basophils is termed as basophilia. Some causes are:

1. Hypothyroidism
2. Certain cancers such as myeloproliferative disorders

Lymphophilia

Lymphophila occur when there is a rise of lymphocytes in the blood. Some causes include

1. Viral infections
2. Some bacterial infections such as tuberculosis
3. Stress
4. Vigorous exercise 
5. Autoimmune conditions such as graves disease or Crohn's disease
6. Cancerous conditions such as Chronic Lymphocytic leukaemia

Symptoms of a high white blood cell count

Symptoms depend on the cause of the high white blood cell count. In the elderly, it is most often due to underlying chronic conditions or medication overuse and side effects. Some non-specific symptoms that can be present are

1. Fever
2. Pain
3. Fatigue
4. Lethargy
5. Signs and symptoms of infections such as pain while passing urine or cough and difficulty in breathing

Complications of high white blood cell in the elderly

A high WBC cell count can indicate severe infections that can spread through the entire body and can be life threatening. This condition is called sepsis.

An incidental finding of high white blood cells in the elderly can be an indication of cancer of the bone marrow known as Chronic Lymphocytic Leukemia. 

Diagnosis

A test called the full blood count (FBC) shows the total number of white blood cells in the blood. It can also give a breakdown of the number of the different types of white blood cells present. 

It is a blood test and the sample is taken from a vein in the forearm. It is a simple test which when coupled with the findings of history and a physical examination can give an overview of the general health of an individual and helps diagnose and assess several health conditions as well as monitor treatment response. 

The test shows the number and different types of cells (“the full blood count”) in the blood along with their shapes and size (“the peripheral smear”).

The blood is composed of the following cells suspended in a fluid called plasma.

·       the erythrocytes or the red blood cells (RBC), that carry oxygen 

·       the leukocytes or the white blood cells (WBC), that fight infections and,

·        the megakaryocytes or the platelets, that stop bleeding.

In addition to this, the FBC can also tell the content of the special red blood cell protein called the haemoglobin which helps the RBC to carry and deliver oxygen.

Normal values on an FBC:

The table below shows the normal values in healthy adults.

* L = litre

** mcL = microliter

*** dL = deciliter [8]

When to see a doctor

Leukocytosis or high WBC count doesn't have many obvious symptoms in the older population as it does in the young.

You should consult a healthcare provider if you are experiencing any of the following symptoms:

1. Fever
2. Recurrent or chronic infection
3. Fatigue
4. Indigestion\ heartburn
5. Nausea vomiting
6. Decreased appetite
7. Lumps and bumps in the body
8. Swollen nodes
9. Enlarged organ
10. Sweating during the night
11. Easy bruising
12. Gum bleeding
13. Unexplained weight loss

When to seek urgent treatment

A white blood cell count greater than 100 000 per mm3 (11 ×109 per L) is a medical emergency. This is because a very high level of WBC cells in the blood can make the blood

 thick and lead to internal bleeding or stroke.

Symptoms to watch out for :

• Stroke symptoms, dizziness, confusion, facial drooping, weakness in body
• Chest pain
• Difficulty breathing
• Blurring of vision
• Sudden severe headache

Treatment

Usually an elevated WBC count is seen when the tests are done to help diagnose any underlying condition that you might be experiencing. It can rarely also be just an anomaly on the test or an unexpected finding on routine testing. If you have a high WBC count on your FBC, contact and discuss this with your doctor. 

As a high WBC count can mean multiple things, your doctor will do further clinical assessment and order additional investigation to find the cause of the high WBC count and treat it accordingly.

Some ways in which high white blood cell count is treated is by

1. Medications such as antibiotics for infection
2. Medications to reduce stress and anxiety
3. Anti-inflammatory medications to reduce inflammation
4. Intravenous fluids to improve blood flow
5. Chemotherapy and radiotherapy for cancer
6. Antihistamines to treat allergic reactions
7. Inhalers to treat asthma

Ways to prevent a high white blood cell count

A rise in the WBC count is the body’s normal response against infection or stress. It helps fight off infection and reduce inflammation and doesn't always need to be prevented.

Having a healthy lifestyle, preventing infections and reducing stress can keep the WBC count within the normal range.

Methods to prevent infections in elderly:

1. Practicing Hand washing 
2. Having good dental hygiene.
3. Avoid contact with sick people
4. Staying up to date with vaccination

Methods to prevent and reduce stress

Long standing stress can pose serious harm and can lead to several health related issues in older adults. Some ways to reduce stress and have a healthier lifestyle are 

1. Quitting smoking
2. Engaging in regular physical activity such as walking, and yoga
3. Spending more time in nature
4. Seeking professional help when needed

Other factors to avoid an increase in WBCs

1. Take medications as prescribed by your healthcare worker.
2. Maintain follow up for any long term conditions such as diabetes, rheumatoid arthritis etc.

Summary

A high WBC count is a frequent finding in routine laboratory testing in the elderly. It is most often due to a normal response of the body due to relatively benign conditions such as infection, inflammation or physical or emotional stress. In some conditions, it can be due to serious bone marrow diseases.

Extremely elevated white blood cells count and clinical factors such as weight loss, bleeding, organ enlargement and abnormalities of RBCs and platelets require urgent medical attention.