Congenital Aplastic Anaemia

Congenital aplastic anaemia is a rare inherited disorder where the bone marrow fails to produce enough blood cells from birth or early childhood, requiring careful diagnosis and specialized treatment.

Table of contents

• What is congenital aplastic anaemia?
• The role of bone marrow
• What causes congenital aplastic anaemia?
• Inherited conditions linked to aplastic anaemia
• Symptoms
• How is it diagnosed?
• Treatment options
• Living with congenital aplastic anaemia

What is congenital aplastic anaemia?

Congenital aplastic anaemia is a disorder where the body fails to produce enough blood cells. The term “congenital” means the condition is present from birth or develops due to inherited genetic factors^[6]. This condition is also called hereditary aplastic anaemia because it is passed down through genes from parent to child, or can be caused by new genetic changes present from birth^[5].

Congenital aplastic anaemia is much less common than the acquired form of the disease. In children with aplastic anaemia, hereditary cases represent about 15 to 20 percent of all cases^[3]. It is usually diagnosed in childhood and often occurs alongside other physical abnormalities^[5].

The role of bone marrow

Bone marrow is a red, spongy material inside your bones. It produces all blood cells that your body needs^[3]. These include three main types of cells, each with a vital function:

• Red blood cells, which contain a protein called hemoglobin that carries oxygen from the lungs to all tissues throughout the body
• White blood cells, which fight infections and protect against bacterial and fungal diseases
• Platelets, which are important for blood to clot and stop bleeding

In congenital aplastic anaemia, stem cells in the bone marrow that produce all these blood-forming cells are destroyed or don’t work properly^[5].

What causes congenital aplastic anaemia?

Hereditary aplastic anaemia is passed down through genes from a parent to a child, or can be caused by a new gene change that occurs before birth^[5]. Most researchers suggest that this stem cell destruction occurs when the body’s immune system attacks its own cells by mistake. It can also be caused by heredity or immune disease^[5].

People who develop hereditary aplastic anaemia often, but not always, have other physical abnormalities^[5]. The condition is usually diagnosed in childhood^[5].

Inherited conditions linked to aplastic anaemia

Some inherited conditions, also called bone marrow failure syndromes, increase the likelihood that a person will develop hereditary aplastic anaemia^[5]. Children may inherit a disorder that makes them more likely to develop aplastic anaemia^[3].

The main inherited conditions that predispose children to developing aplastic anaemia include:

• Fanconi anemia – the most common hereditary cause of aplastic anaemia^[4]
• Dyskeratosis congenita
• Shwachman-Diamond syndrome
• Diamond-Blackfan anemia
• Amegakaryocytic thrombocytopenia
• Pearson syndrome^[2]

Fanconi anemia is a genetically diverse disorder characterized by a variety of birth defects, progressive reduction in blood cells, and susceptibility to blood cancers and solid tumors. Each patient has a unique set of abnormalities that can affect any major organ system or skeletal development^[8].

Diamond-Blackfan anemia is an uncommon condition that often appears in the first few months of life. About 40 to 45 percent of Diamond-Blackfan anemia cases are familial with a specific inheritance pattern, while the remaining cases occur sporadically^[8].

Symptoms

The symptoms of congenital aplastic anaemia develop when blood cells aren’t replaced fast enough. Red blood cells live for about 120 days, platelets for about 7 to 10 days, and certain white blood cells for less than 1 day in the bloodstream^[16].

Each child may experience symptoms differently, but the most common symptoms include^[3]:

• Lack of energy or tiring easily (fatigue)
• Pale skin, lips, and hands, or paleness under the eyelids
• Shortness of breath
• Fevers or infections
• Bleeding, such as bruising, bleeding gums, nosebleeds, or blood in the stool
• Irregular heartbeat
• Dizziness or headache

Symptoms usually develop over weeks and months, so changes may not be noticed right away. In some cases, children have immediate severe symptoms^[2].

It is important to understand that some symptoms of anaemia may resemble those of other more common medical problems or other blood disorders. Because some of these symptoms can also point to other conditions, it’s important to have your child evaluated by a qualified medical professional for an accurate diagnosis and prompt treatment^[3].

How is it diagnosed?

In addition to a complete medical history and physical examination, congenital aplastic anaemia can only be diagnosed accurately by a full evaluation of the blood and bone marrow^[3].

Healthcare providers diagnose aplastic anaemia by doing physical examinations, blood tests and genetic tests. Tests may include^[2]:

• Complete blood count (CBC) with differential – This tests and measures your blood cells, including all five types of white blood cells
• Peripheral blood smear – Medical specialists examine blood cells and platelets under a microscope
• Bone marrow biopsy – A needle is used to remove a small sample of bone marrow from a large bone. The sample is examined under a microscope to rule out other blood-related diseases. In aplastic anaemia, bone marrow contains fewer blood cells than normal^[1]

Because treatment for congenital aplastic anaemia differs from management of other diseases affecting the bone marrow, it is critically important to distinguish between these disorders when a diagnosis is suspected. Congenital aplastic anaemia resembles other bone marrow disorders such as myelodysplastic syndrome, certain infections, and leukemia^[14].

Therefore, children with persistently low blood counts should be evaluated by pediatric blood specialists with expertise in diagnostics and treatment of these uncommon disorders^[14].

Treatment options

Treatment for congenital aplastic anaemia will depend on the age of the child and how severe the anaemia is. Treatments often need to be repeated, and sometimes several types of treatment may be tried in order to find the one that works best^[16].

Your child’s treatment may be managed by a hematologist, a healthcare provider who specializes in blood disorders^[16]. Currently, the only proven therapies to restore the ability of the bone marrow to make blood cells are either medications to intensely suppress the immune system or a bone marrow transplant (also known as a hematopoietic stem cell transplant)^[14].

Treatment approaches may include^[16]:

• Blood transfusions – These provide blood cells that the bone marrow isn’t producing and can help control bleeding and relieve symptoms
• Medicines to cause blood cell production
• Bone marrow transplantation – Replacing your child’s bone marrow with healthy bone marrow from a donor

A stem cell transplantation is the only cure for aplastic anaemia^[2]. For certain patients with inherited bone marrow failure syndromes, hematopoietic stem cell transplantation remains the treatment of choice when bone marrow fails^[8].

Treatment also includes temporarily supporting patients with transfusions and antibiotics to treat infections^[14].

Living with congenital aplastic anaemia

During and between treatments, it’s important to prevent complications of aplastic anaemia caused by infections, bleeding, or extreme tiredness. This is very important when blood cell counts are low^[16].

Safe nutrition

It’s important for your child to eat a healthy diet. Your child may be at risk for foodborne illness. Because of this, they may need to avoid aged cheeses or unpasteurized milk or juices. Your child should not eat undercooked or raw foods. Make sure to cook all foods fully. Wash and peel fresh fruits and vegetables before serving. Don’t let your child eat at salad bars or restaurant buffets^[16].

Safe exercise

Regular exercise and playtime are important, and so is resting between activities. If your child gets short of breath when active, let your provider know. Because your child may be at risk for bleeding, infection, and fatigue, contact sports are usually discouraged. If your child is school-age, work with teachers and coaches so your child can take part safely in peer activities^[16].

Preventing infection

Make sure your child gets a flu shot every year and ask their provider about other preventive vaccines. Stay away from crowds and sick friends or relatives, especially during cold and flu season. Remind your child—and the rest of the family—to wash hands often. Regular dental care will help prevent tooth and gum infections. Keep your child out of public pools and hot tubs, especially if your child’s skin has any open cuts or scrapes. Don’t let anyone smoke around your child, including in your home and car^[16].

Support and education

Learn as much as you can about congenital aplastic anaemia and work closely with your child’s hematologist and treatment team. A serious and recurrent illness like aplastic anaemia is stressful for both you and your child. Make sure you both get the support you need^[16].

In an age-appropriate manner, include your child in the medical process. Educate them about their condition and encourage them to write down questions to ask during medical appointments^[20].