Causes
Red blood cell membrane proteins, including spectrin, ankyrin, band 3, and protein 4.2, are defective in hereditary spherocytosis (HS). The red blood cells become spherical and fragile when these genes are mutated, causing them to become shaped and flexible.
Symptoms
Hereditary spherocytosis may cause the following symptoms:
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Symptoms of anemia include fatigue, weakness, and pallor due to low red blood cell counts (hemolytic anemia).
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In jaundice, red blood cells are broken down and bilirubin levels are elevated, resulting in yellowing of the skin and eyes.
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Splenomegaly: An enlarged spleen caused by increased destruction of abnormal red blood cells by the spleen.
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In the gallbladder, gallstones (cholelithiasis) are formed when excess bilirubin is produced and precipitates.
Diagnosis
Hereditary spherocytosis is typically diagnosed by:
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The complete blood count (CBC) measures red blood cell parameters including hemoglobin, hematocrit, and mean corpuscular volume (MCV). A peripheral blood smear may reveal characteristic spherocytes.
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Measurement of serum bilirubin levels to detect hemolysis and jaundice.
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A spleen ultrasound or other imaging study may be used to assess for splenic complications, such as splenic infarction or splenic sequestration.
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A genetic test can identify mutations in the genes encoding spectrin, ankyrin, or other proteins of the red blood cell membrane that are associated with hereditary spherocytosis.
Treatment
Symptoms of hereditary spherocytosis are managed, complications are prevented, and hemolytic crises are reduced through treatment. Treatment options include:
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Supplementation with folic acid supports red blood cell production and prevents folate deficiency.
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Red blood cells may need to be transfused in severe cases of anemia or hemolytic crisis.
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Individuals with severe hemolysis, symptomatic anemia, or recurrent complications such as gallstones or splenic sequestration may benefit from splenectomy surgery.
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Individuals with symptomatic gallstones may benefit from surgical removal of the gallbladder (cholecystectomy).
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It may be recommended to use supportive measures such as hydration, pain management, and to avoid triggers for hemolysis (e.g., certain medications, infections).
Prevention
In addition to genetic counseling, individuals with a family history of hereditary spherocytosis may benefit from genetic counseling to understand their risk of inheriting the condition and discuss family planning options.
Conclusion
Red blood cells that are spherical and fragile are the result of hereditary spherocytosis, a genetic disorder caused by defects in the membrane proteins of the red blood cells. A diagnosis usually involves blood tests, imaging studies, and genetic tests. Supportive measures, blood transfusions, splenectomy, and gallbladder surgery may be used to manage symptoms and prevent complications. In individuals with a family history of hereditary spherocytosis, genetic counseling may be helpful.
