What Is Anaemia?

Introduction

Anaemia is a prevalent medical condition characterised by a deficiency in red blood cells or haemoglobin, impairing the blood's ability to carry sufficient oxygen to body tissues. This insufficiency often leads to fatigue, shortness of breath, headaches and irregular heartbeat. 

Anaemia can arise from various causes, including: 

• Nutritional deficiencies (such as iron, vitamin B12, or folic acid)
• Chronic diseases
• Genetic factors 
• Underlying health issues 

The occurrence of anaemia tends to rise with age and is more often observed in people assigned female at birth (AFAB), of reproductive age or pregnant, than people assigned male at birth (AMAB) and in the elderly population.¹ In this article, we will delve into the symptoms, types, risk factors, diagnosis and treatment options of anaemia.

Grading of anaemia

According to the World Health Organization, anaemia can be diagnosed based on haemoglobin levels (g/litre).

Types of anaemia

Anaemia is a condition caused by a reduced number of red blood cells or a decreased ability of red blood cells to carry oxygen.¹ There are many different types of anaemia, each with its underlying causes. Some of the most common types of anaemia include: 

Iron-deficiency anaemia

This is the most common type of anaemia and is often caused by a lack of iron in the diet or poor iron absorption in the body. Iron is necessary for the production of haemoglobin, the protein in red blood cells that carries oxygen.² 

Megaloblastic anaemia

Megaloblastic anaemia is a type of blood disorder characterised by the presence of abnormally large and immature red blood cells (megaloblasts) in the bone marrow. It primarily stems from deficiencies in vitamin B12 or folic acid, essential for DNA synthesis and proper cell division.³

Haemolytic anaemia

This type of anaemia occurs when the red blood cells are destroyed faster than the body can produce them. It can be caused by various factors, including autoimmune conditions, inherited disorders, or infections such as malaria.⁴

Aplastic anaemia

In aplastic anaemia, the bone marrow fails to produce enough red blood cells, white blood cells, and platelets. It can be acquired or inherited and may be caused by factors like exposure to benzene or radiation.⁵

Sickle cell anaemia

Sickle cell anaemia is a genetic disorder in which the red blood cells have an abnormal shape, leading to blockages in blood vessels, pain, and reduced oxygen-carrying capacity.⁶

Thalassaemia

Thalassaemia is a genetic blood disorder characterized by abnormal haemoglobin production, affecting the red blood cells' ability to transport oxygen effectively, leading to anaemia. There are two main types: alpha (α) thalassaemia and beta (ꞵ) thalassaemia, each with various subtypes and severity levels.

Pernicious anaemia

Pernicious anaemia is an autoimmune disorder where the body's immune system attacks the cells in the stomach that produce intrinsic factor, which is necessary for the absorption of vitamin B12.⁷

Macrocytic anaemia

Macrocytic anaemia is a type of anaemia characterised by abnormally large red blood cells (macrocytes). This condition often results from deficiencies in vitamin B12 or folic acid. This can be further categorised into megaloblastic and non-megaloblastic types. 

Microcytic anaemia

Microcytic anaemia is a type of blood disorder characterised by smaller-than-normal red blood cells. This condition often results from insufficient haemoglobin production or impaired iron utilisation.

Normocytic anaemia

Normocytic anaemia is a type of blood disorder characterised by red blood cells that are within the normal size range but insufficient in quantity, leading to decreased haemoglobin levels. This condition often arises from underlying health issues such as kidney failure, inflammation, or bone marrow disorders. 

Diamond-Blackfan anaemia

This type of anaemia is a rare genetic disorder that affects the bone marrow's ability to produce red blood cells, typically present in early childhood.

Sideroblastic anaemia

Sideroblastic anaemia is a rare blood disorder where too much iron builds up in developing red blood cells, making it hard for them to carry oxygen. This condition can occur because of genetic issues or certain health problems, such as alcohol use syndrome or heavy metal poisoning.

Fanconi anaemia

Fanconi anaemia is a rare genetic disorder affecting the bone marrow, characterised by a diminished ability to repair damaged DNA. This condition can lead to bone marrow failure, congenital anomalies, and an increased risk of certain cancers. 

Symptoms of anaemia

The common symptoms of anaemia include–

• Fatigue
• Shortness of breath
• Dizziness
• Cold hands and feet
• Headache

The symptoms of more severe anaemia include:

• Pale skin
• Increased heart rate
• Rapid breathing
• Tendency to bruise more easily

Risk factors of anaemia

The risk factors associated with the development of anaemia are–

Age and gender

Infants, young children, and pregnant people AFAB are at a higher risk of developing anaemia due to increased nutritional demands. Additionally, elderly people may be prone to anaemia due to age-related changes in the digestive system and decreased nutrient absorption.

Nutritional factors

A well-balanced diet is crucial for preventing nutritional deficiencies that contribute to anaemia. Diets low in iron, vitamin B12, and folate can increase the risk. 

Chronic diseases

Certain chronic conditions, such as inflammatory bowel disease, chronic kidney, liver and thyroid disease, and autoimmune diseases (such as rheumatoid arthritis), can contribute to anaemia. Inflammation can affect the body's ability to use iron and other nutrients necessary for red blood cell production.

Genetic factors

Genetic factors play a significant role in some types of anaemia, such as sickle cell anaemia and thalassaemia. Individuals with a family history of these conditions may have an increased risk of developing them.

Pregnancy

Pregnancy often leads to an increased demand for iron to support the growing baby. If dietary iron intake is insufficient, or if there are complications during pregnancy, the risk of developing iron-deficiency anaemia rises.¹ 

Diagnosis of anaemia

The diagnosis of anaemia is done by medical history and laboratory tests. The tests include–

Blood tests

These blood tests can help to diagnose anaemia:

Complete blood count (CBC)

A CBC is a standard blood test that measures the number of red blood cells, white blood cells, and platelets in the bloodstream. The size and shape of red blood cells can indicate the presence of anaemia.⁸

Peripheral blood smear

A peripheral blood smear involves examining a small sample of blood under a microscope to assess the size, shape, and number of red blood cells. This can help identify abnormal cell characteristics of different types of anaemia.⁸

Iron studies

Iron studies measure various markers, including serum iron, ferritin, and transferrin saturation, to evaluate the body's iron status. Low iron levels may indicate iron deficiency anaemia.⁸

Vitamin B12 and folate levels

Blood tests specifically measuring vitamin B12 and folate levels can help diagnose deficiencies that lead to certain types of anaemia.⁸

Bone marrow examination

In some cases, a bone marrow examination may be necessary to determine the cause of anaemia. This invasive procedure involves extracting a small sample of bone marrow for analysis.⁸

Treatment of anaemia

The treatment of anaemia depends on the underlying cause and severity of the condition. Here are some of the approaches to treat anaemia–

Iron supplements

For iron deficiency anaemia, iron supplements are often prescribed to increase iron levels in the body. 

Vitamin supplements

A deficiency of Vitamin B12 and folate can cause anaemia. In such cases, supplementation of these vitamins may be recommended. Vitamin B12 can be given by injection if the deficiency is severe.

Blood transfusions

In cases of severe anaemia, blood transfusions may be required to quickly restore the number of red blood cells in the bloodstream. This is often done in emergencies or for individuals who cannot tolerate other forms of treatment.

Medications

Certain medications, such as immunosuppressants, may be prescribed for haemolytic anaemias or conditions where the immune system is attacking red blood cells. Managing the underlying cause is crucial for effective treatment.

Bone marrow transplant

For severe aplastic anaemia or certain genetic forms of anaemia, a bone marrow transplant may be considered. This procedure involves replacing damaged or nonfunctional bone marrow with healthy donor marrow.

FAQs

What is the main cause of anaemia?

The main cause of anaemia is a deficiency in red blood cells or haemoglobin, impairing the blood's ability to carry oxygen. Common causes include insufficient iron, vitamin B12, or folic acid intake, as well as chronic diseases, genetic conditions, or blood loss. 

What are the three symptoms of anaemia?

Common symptoms of anaemia include fatigue, weakness, and pale skin. Individuals with anaemia may also experience irregular heartbeats, shortness of breath, dizziness, headaches, and cold hands and feet. 

How can anaemia be cured?

The treatment of anaemia depends on its underlying cause and the severity of the condition. Common approaches include iron supplements for iron-deficiency anaemia, vitamin supplements for vitamin deficiencies, and addressing the root cause, such as treating underlying medical conditions or stopping excessive bleeding. A balanced diet and lifestyle changes can also contribute to recovery.

Summary

Anaemia is a medical condition characterised by a deficiency of red blood cells or haemoglobin in the blood, leading to insufficient oxygen transport to body tissues. The common symptoms of anaemia include fatigue, weakness, and shortness of breath. The causes include nutritional deficiencies, chronic diseases, or genetic factors affecting red blood cell production or lifespan.

Anaemia can be diagnosed using blood tests that measure haemoglobin levels. Treatment depends on the underlying cause and may include dietary supplements, medications, or addressing the root issue. Anaemia can impact overall health and requires medical evaluation for appropriate management and prevention of complications.