Hereditary Spherocytosis
Posted October 4, 2022 by Anusha ‐ 4 min read
Hereditary spherocytosis is an inherited blood disorder that causes hemolytic anemia. This anemia happens when your red blood cells break down faster than normal. In hereditary spherocytosis, your red blood cells lose their characteristic disk-like shape, becoming round or spherical cells (spherocytes) that are removed from circulation faster than normal red blood cells.
Causes of Hereditary spherocytosis
As the name implies, people inherit this condition from their biological parents.
Everyone receives copies of their biological parents’ genes.
Inherited disorders happen when genes passed on from parent to child mutate or change.
In hereditary spherocytosis, parents may pass on mutations in five different genes.
These genes provide instructions to proteins that make up part of red blood cells’ infrastructure.
About 75% of people who have hereditary spherocytosis inherit the condition in an autosomal dominant manner.
That means it only takes one copy of the responsible gene to cause some form of hereditary spherocytosis.
Children born to a parent who has the mutated gene have a 50% chance of inheriting the mutated gene.
Other people inherit the condition because they received one copy of mutated genes from each parent.
This is autosomal recessive manner.
In this case, parents are carriers but usually don’t have hereditary spherocytosis signs or symptoms.
When people who are carriers have children, each child has a different chance of developing hereditary spherocytosis.
Specifically, they have a 25% chance of developing the condition, a 50% chance of being a carrier but not developing the condition, and a 25% chance of avoiding being a carrier and having hereditary spherocytosis.
Categories of Hereditary spherocytosis
Mild: This category includes about 20% to 30% of people who have hereditary spherocytosis. People in this category have hemolytic anemia. They typically don’t have other symptoms until they’re in their 30s or 40s.
Moderate: This category includes babies and children who have hereditary spherocytosis and represents 60% to 75% of all people who have the condition. Babies and children may have mild to moderate hemolytic anemia and jaundice.
Severe: This category represents 5% of all people who have hereditary spherocytosis. It includes newborns who develop severe anemia symptoms when they’re about a week old.
Symptoms of Hereditary spherocytosis
Shortness of breath (dyspnea): This happens when you don’t have enough red blood cells carrying oxygen throughout your body.
Fatigue: Fatigue is a sensation of being so tired that it affects your daily life and your ability to do your daily activities.
Fast heartbeat (tachycardia): This condition means your heart is beating faster than it should. When your heart beats too fast, it doesn’t have enough time between beats to fill up with blood, and your heart can’t supply your body with the oxygen it needs.
Low blood pressure (hypotension): Low blood pressure can be a symptom or a condition. It happens when your blood pressure is much lower than expected.
Diagnosis of Hereditary spherocytosis
Healthcare providers diagnose the condition by evaluating your symptoms, asking questions about your medical history and biological family medical history, and by doing several tests. This test may include:
Complete blood count (CBC): This test gives healthcare providers information about your blood and overall health.
Peripheral blood smear: Healthcare providers do this test to examine your blood cells’ size and shape.
Reticulocyte count: Healthcare providers measure reticulocytes to find out if your bone marrow is producing enough healthy red blood cells.
Direct antiglobulin (Coombs) test: This test checks for autoimmune hemolytic anemia.
Bilirubin level: This is a blood test to check for high bilirubin levels.
Red cell osmotic fragility: This test detects whether red blood cells are likely to break down.
Plasma membrane electrophoresis: This is a technique that uses gel or fluid on an electric field to identify DNA, RNA or proteins. Healthcare providers use this test to identify which red cell membrane protein has mutated or changed.
Treatment of Hereditary spherocytosis
Phototherapy: Light treatment for jaundice in newborns.
Blood transfusions: Healthcare providers may treat anemia with blood transfusions.
Splenectomy: This is surgery to remove your spleen. Healthcare providers may treat severe forms of hereditary spherocytosis by removing your spleen.
Gallbladder removal (cholecystectomy): This surgery treats gallstones.
Iron chelation therapy: People who have blood transfusions may develop iron overload (hemochromatosis). Iron chelation therapy removes extra iron.