Sickle cell anemia: Symptoms, Causes, Diagnosis & Treatment

 

One of the inherited disorders collectively called sickle cell disease is sickle cell anemia. This condition impacts the structure of red blood cells, which carry oxygen to all parts of the body.

Because red blood cells are often round and flexible, blood vessels can accommodate them with ease. Certain red blood cells with sickle cell anemia have a sickle or crescent moon shape. Additionally, these sickle cells harden and stick which may block or delay blood flow.

The goal of the present treatment strategy is to reduce discomfort and assist in avoiding further consequences of the disease. Newer therapies, nevertheless, could be able to cure people of the disease.

A severe variation of sickle cell disease, an inherited blood disorder, is sickle cell anemia. It is brought on by genetic changes or mutations, which result in anemia and aberrant red blood cells. Fatigue, infections, and painful tissue damage are symptoms. About half of sickle cell anemia patients survive into their 50s now, mostly due to early discovery and innovative treatments.

Also Read: Iron-Deficiency Anemia: Symptoms, Causes, Risk factors, Treatments & Prevention

What is sickle cell anemia?

The most severe form of sickle cell disease, an inherited blood condition, is sickle cell anemia. A genetic mutation (change) that results in abnormal C- or sickle-shaped red blood cells is inherited in sickle cell anemia. Medical professionals may refer to these cells as "sickled cells."

Round, flexible disks make up normal red blood cells. As they pass through your blood blood vessels, oxygen is delivered to your tissues and organs. Sticky, rigid cells called sickled cells cling to your blood vessels and prevent blood from moving freely throughout your body. Additionally, sickled red blood cells degrade and expire more quickly than healthy red blood cells. Consequently, red blood cell production is impacted by sickle cell anemia, leading to the development of severe anemia (low red blood cell levels).

Sickle cell anemia complications can pose a serious threat to life. In the past, there was a low adult survival rate for newborns with this illness. More people are living longer into their 50s now because of early identification and innovative treatments.

Symptoms:

Sickle cell anemia symptoms typically start to show up at six months of age. They differ from person to person and are subject to change. Among the symptoms are:

• Anemia. Sickle cells are brittle and eventually die. Red blood cells require replacement after an average of 120 days of life. However, sickle cells often expire within 10 to 20 days, resulting in a deficiency of red blood cells. We call this anemia. The body cannot acquire enough oxygen if there are not enough red blood cells. It wears you out.

• Episodes of pain. Agony crises, which are recurring episodes of extreme pain, are one of the main signs of sickle cell anemia. When red blood cells with a sickle shape obstruct blood flow to the chest, abdomen, and joints, pain results.

• The discomfort might last anywhere from a few hours to many days, depending on its strength. Some people experience few to no pain crises annually. Some people have twelve or more in a year. A hospital stay is necessary for a serious pain crisis.

• Sickle cell anemia patients may also have persistent discomfort from ulcers, damaged bones and joints, and other conditions.

• Swelling in the feet and hands. Red blood cells with a sickle shape obstruct blood flow to the hands and feet, causing swelling.

• Frequent infections. The spleen plays a crucial role in infection prevention. The spleen may sustain damage from sickle cells, increasing the likelihood of infections. Vaccinations and antibiotics are frequently administered to infants and young children with sickle cell anemia to prevent potentially life-threatening illnesses like pneumonia.

• Delayed puberty or growth. The body gets its oxygen and nutrition from red blood cells, which are essential for growth. Inadequate red blood cell production can impede the growth of infants and children and delay teenage puberty.

• Problems with vision. Sickle cells can clog the tiny blood arteries that supply the eyes' blood supply. This may cause vision issues by harming the retina, the area of the eye responsible for processing visual images.

Causes:

The gene that instructs the body to produce hemoglobin is altered, leading to sickle cell anemia. Red blood cells' iron-rich component, hemoglobin, enables the body's tissues to absorb oxygen from the lungs and distribute it throughout the cell. Red blood cells in sickle cell anemia are deformed, sticky, and hard due to the hemoglobin associated with the condition.

A child must inherit both copies of the sickle cell gene from both parents to have sickle cell anemia.

A child will have the sickle cell trait if just one parent passes on the sickle cell gene to them. People who have the sickle cell trait produce both sickle cell and usual hemoglobin because they have one sickle cell gene and one typical hemoglobin gene.

While sickle cells may be present in their blood, individuals usually don't exhibit any symptoms. They are the disease's carriers. This implies that they can give the gene to their progeny.

Complications:

Complications from sickle cell anemia can be serious and occasionally fatal. For instance, sickle cell anemia patients may require emergency care or hospital admission due to consequences such as acute chest syndrome (ACS) or vaso-occlusive crisis (VOC).

The following are other sickle cell anemia complications:

• Chronic kidney disease, resulting from tissue damage caused by oxygen deficiency.

• If sickled cells obstruct blood arteries in your retina, you may have detached retinas.

• Priapism, or uncomfortable erections, is caused by clogged blood vessels in the penis.

• If sickled cells become lodged in your spleen and impair blood flow, you may have splenic sequestration. Acute anemia from splenic sequestration frequently occurs.

• Stroke is a potential complication for individuals with sickle cell anemia, including infants (pediatric stroke).

Acute chest s (ACS)
The most typical sickle cell anemia consequence is acute chest syndrome (ACS). In addition, it ranks as the second most frequent reason for hospital admission and the most prevalent cause of mortality. It occurs when clumps of sickled cells block blood veins in your lungs. Among the symptoms are:

• Sudden discomfort in the chest

• Cough

• Fever

• Trouble breathing

VOC, or vaso-occlusive crisis

This is known as a vaso-occlusive event, which occurs when sickled cells obstruct blood channels. This situation may be referred to by medical professionals as an "acute pain crisis." You may experience severe discomfort in your lower back, arms, legs, and abdomen while using VOC.

VOC is sometimes referred to by providers as "the invisible illness." Often, the only symptom brought on by VOC is pain. People are unable to identify a sickness or damage. They merely hurt.

The only treatment for vaso-occlusive crises is opioid medication. According to studies, patients with sickle cell anemia face stigma since they must take opioid medications to control volatile organic compounds (VOCs). Anxiety and sadness might result from having to live with that stigma.

 Diagnosis:

Medical professionals use a physical examination, which may involve feeling your liver or spleen, to identify sickle cell anemia. They'll inquire about your symptoms, especially any arm, leg, or abdominal pain. Your medical history, including any infections, might be questioned. The following tests are possible to order:

• A complete blood count (CBC): involves some tests to determine the condition of your red blood cells.

• Hemoglobin electrophoresis: Alternatively referred to as high-performance liquid chromatography, this test looks for and measures the abnormal hemoglobin that is the cause of sickle cell anemia in your blood.

• Genetic testing: To determine whether you have genetic changes (mutations) that lead to sickle cell anemia, your doctor may prescribe tests.

How does one treat sickle cell anemia?

The course of treatment for sickle cell anemia is determined by your general health and symptoms. For instance, an allogeneic stem cell transplant may be advised by your physician if you experience serious problems such as acute chest syndrome, recurrent acute pain crises, or stroke. The sole treatment for sickle cell anemia is this operation.

Blood transfusions, medicines to cure infections, and medicines to relieve particular symptoms are other treatments for sickle cell anemia. Among those drugs are:

• The medication Hydroxyurea (also known as Droxia®, Hydrea®, Siklos®, and Mylocel®) is an anticancer agent. It's a treatment for adults, children, and babies between the ages of six and nine months. It might lessen the frequency of major problems and lessen the symptoms of anemia.

• Voxelotor (Obryta®): Prevents sickled cells from forming in red blood cells. It's a therapy for kids four years old and up.

• L-glutamine therapy (Endari®): This drug prevents sickled cells from growing even more aberrant. It is prescribed for adults and children five years of age and above.

• Adakveo® (crizanlizumab-tmca): This lessens the likelihood of VOC/acute pain crises. It is a treatment for those age 16 and older.

References:

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• Sickle cell disease. National Heart, Lung, and Blood Institute. https://www.nhlbi.nih.gov/health-topics/sickle-cell-disease. Accessed Aug. 4, 2023.

• Hoffman R, et al. Pain Management and Antiemetic Therapy in Hematologic Disorders. In: Hematology: Basic Principles and Practice. 8th ed. Elsevier; 2023. https://www.clinicalkey.com. Accessed Aug. 4, 2023.

• Tisdale JF, Thein SL, Eaton WA. Treating sickle cell anemia (https://pubmed.ncbi.nlm.nih.gov/32165573/). Science. 2020 Mar 13;367(6483):1198-1199. Accessed 8/21/2024.

• Linton EA, Goodin DA, Hankins JS, et al. Sickle Cell Disease Implementation Consortium. A Survey-Based Needs Assessment of Barriers to Optimal Sickle Cell Disease Care in the Emergency Department (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7511000/?msclkid=a62e1ef8c63811ec9825a097cc3cb9d1). Ann Emerg Med. 2020;76(3S):S64-S72. Accessed 8/21/2024.

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• Mangla A, Ehsan M, Agarwal N, Maruvada S. Sickle Cell Anemia (https://www.ncbi.nlm.nih.gov/books/NBK482164/?msclkid=f19effc8c63911ec8fd8af18bade5b94). In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Updated 8/4/2023. Accessed 8/21/2024.

• Casgevy (prescribing information). Vertex Pharmaceuticals; 2023. https://www.fda.gov/vaccines-blood-biologics/casgevy. Accessed Dec. 11, 2023.