Definition

Hemolytic anemia is a blood disorder where red blood cells break down or die faster than normal. Typically, red blood cells have a lifespan of about 120 days. However, if they are destroyed or die prematurely, the bone marrow doesn't have enough time to produce new red blood cells, resulting in anemia or a reduced number of red blood cells.

Other types of anemia can occur when there is excessive bleeding, causing red blood cells to be depleted faster than the body can produce new ones to replace the lost ones. Another type of anemia can occur when conditions affect the production of red blood cells in the body, resulting in fewer red blood cells than usual or producing abnormal red blood cells.

Hemolytic anemia is less common than anemia caused by excessive bleeding or low red blood cell production. Patients with hemolytic anemia may be caused by genetic conditions that result in anemia. Some people may have mild symptoms of hemolytic anemia that can disappear with treatment.

Causes

Hemolytic anemia can be caused by genetic conditions that affect red blood cells. Additionally, certain infections or receiving blood transfusions from donors with incompatible blood types can lead to conditions affecting red blood cells. Besides genetic conditions, infections can also cause hemolytic anemia.

Some genetic conditions include:

• Sickle cell anemia: The body produces abnormally shaped red blood cells that can get trapped in small blood vessels and the liver.
• Thalassemia: One of the genetic blood disorders that causes your body to form red blood cells that are easily broken down.
• G6PD deficiency: A genetic disorder affecting an enzyme that protects red blood cells. Red blood cells become susceptible to certain infections or medications when the enzyme levels drop, leading to easy breakdown.

Infections related to or capable of causing hemolytic anemia include:

• Malaria: This disease occurs when mosquitoes infected with the malaria parasite bite humans, introducing the parasite into the bloodstream. If left untreated, malaria can lead to hemolytic anemia.
• Rocky Mountain spotted fever: This infection occurs when ticks infected with the bacterium Rickettsia rickettsii bite humans.
• Haemophilus influenzae disease: Caused by the Haemophilus influenzae bacterium.
• Human immunodeficiency virus (HIV): This virus causes a decline in the body's immunity and leads to Acquired Immunodeficiency Syndrome (AIDS).

In addition to these causes, other possible triggers of hemolytic anemia include autoimmune disorders, where the immune system mistakenly identifies red blood cells as foreign objects, leading to their destruction. Other factors include exposure to certain chemicals, drugs, or toxins, infections, blood clots in blood vessels, and blood transfusions with incompatible blood types.

Risk factor

The risk factors for hemolytic anemia involve damage to red blood cells and can broadly be categorized into oxidative stress, physical injury, and genetic conditions. Oxidative stress is particularly associated with G6PD deficiency, which can occur due to the effects of medication use. Medications such as Primaquine for malaria treatment, Dapsone for PCP or leprosy, and sulfa drugs for skin treatment, urinary tract infections, or other infections can exacerbate G6PD deficiency and contribute to hemolytic anemia.

Symptoms

The severity of hemolytic anemia can range from moderate to severe, and symptoms may manifest suddenly or gradually.

Some symptoms that may appear include:

• Jaundice: This condition causes the skin, whites of the eyes (sclera), and mucous membranes to turn yellow. It occurs when there is a high level of bilirubin due to the breakdown of red blood cells.
• Shortness of breath (dyspnea) occurs when the body doesn't have enough red blood cells to carry oxygen throughout, resulting in difficulty breathing.
• Fatigue
• Rapid heart rate (tachycardia)
• Low blood pressure
• The presence of blood in the urine (hematuria), can occur as a symptom of sickle cell anemia.
• Enlargement of the spleen or liver: The spleen and liver filter red blood cells as they move through the body. Damaged or dying red blood cells can become trapped in these organs, leading to their destruction. Enlargement of these organs can indicate damage to red blood cells.

Diagnosis

Diagnosing hemolytic anemia begins with doctors asking several questions about the patient's medical history, particularly focusing on any family history of anemia, specific infections, or medications that could contribute to hemolytic anemia. A focused physical examination follows, during which doctors observe for signs and symptoms of anemia, jaundice, and enlargement of the liver or spleen.

Doctors typically recommend blood tests to confirm the diagnosis. These may include genetic marker testing, which can indicate whether a genetic condition underlies the hemolytic anemia.

An initial test often performed is a complete blood count (CBC). This test examines the quantity and size of red blood cells, white blood cells, and platelets, as well as measures hemoglobin (a protein that carries oxygen) and hematocrit (the proportion of red blood cells in the blood).

Management

Treatment for hemolytic anemia is tailored to the severity of symptoms and the underlying cause. Doctors may recommend a blood transfusion to stabilize the red blood cell count in severe symptoms. Additionally, doctors will diagnose the underlying cause of the anemia to determine the appropriate treatment.

Complications

Untreated or poorly managed hemolytic anemia can lead to complications such as irregular heart rhythms, cardiac muscle abnormalities, and heart failure. 

Prevention

Hemolytic anemia caused by genetic factors cannot be prevented, but individuals can consult with a doctor to understand the likelihood of passing on the disease to their children. If hemolytic anemia is caused by medication side effects, patients can discuss alternative medications with their doctor or, if necessary, avoid drugs that trigger hemolytic anemia.

Preventing hemolytic anemia involves taking measures to prevent infections. This includes avoiding direct contact with infected individuals, minimizing time spent in crowded places, practicing regular handwashing and dental hygiene, refraining from consuming raw or undercooked food, and getting an annual flu vaccination.

When to see a doctor?

If you experience symptoms of hemolytic anemia, it's essential to contact a doctor for further consultation promptly. Similarly, if you have a personal or family history of autoimmune conditions or are taking medications known to have side effects of hemolytic anemia, it's important to consult with a doctor promptly. Additionally, undergoing regular check-ups allows for monitoring and discussion of the disease and any potential side effects of medication.

Looking for more information about other diseases? Click here!