Summary about Disease
Hereditary spherocytosis (HS) is an inherited blood disorder characterized by the production of red blood cells that are sphere-shaped (spherocytes) instead of the normal biconcave disc shape. This abnormal shape makes the red blood cells more fragile and susceptible to premature destruction by the spleen, leading to hemolytic anemia. The severity of HS varies widely, ranging from mild to severe.
Symptoms
Anemia (fatigue, weakness, paleness)
Jaundice (yellowing of the skin and whites of the eyes)
Splenomegaly (enlarged spleen)
Gallstones (pigment gallstones are common)
Dark urine (due to bilirubin excretion)
Abdominal pain (related to gallstones or splenomegaly)
Growth delay in children (in severe cases)
Causes
HS is caused by mutations in genes that encode proteins of the red blood cell membrane skeleton. These proteins, such as spectrin, ankyrin, band 3, and protein 4.2, are essential for maintaining the normal shape and flexibility of red blood cells. Mutations in these genes disrupt the structure and stability of the cell membrane, leading to the formation of spherocytes. HS is typically inherited in an autosomal dominant pattern, meaning that only one copy of the mutated gene is needed to cause the disorder. However, autosomal recessive inheritance and spontaneous mutations can also occur.
Medicine Used
4. Medicine used
Folic acid: Supplementation is often prescribed to support red blood cell production, as the bone marrow works harder to compensate for the red blood cell destruction.
Iron supplementation: In some cases, iron deficiency can coexist with HS. Iron supplements are prescribed if iron deficiency is present.
Vaccinations: Individuals with HS, especially those who have undergone splenectomy, should receive vaccinations against encapsulated bacteria such as Streptococcus pneumoniae, *Haemophilus influenzae* type b (Hib), and *Neisseria meningitidis*.
Blood transfusions: In severe cases of anemia, blood transfusions may be necessary to temporarily increase the red blood cell count.
Ursodeoxycholic acid (ursodiol): Used to help prevent or dissolve gallstones.
Is Communicable
No, hereditary spherocytosis is not communicable. It is a genetic disorder, meaning it is caused by inherited gene mutations and cannot be spread from person to person.
Precautions
Genetic counseling: Families with a history of HS should consider genetic counseling to understand the inheritance pattern and the risk of passing the condition on to their children.
Medical monitoring: Regular medical checkups and blood tests are important to monitor the severity of anemia, liver function, and other potential complications.
Avoidance of triggers: Certain factors, such as infections or exposure to certain drugs, can trigger hemolytic crises in individuals with HS. It's important to identify and avoid these triggers.
Infection prevention: Take steps to prevent infections, such as practicing good hygiene and getting vaccinated against common illnesses.
Healthy lifestyle: Maintaining a healthy diet and getting regular exercise can help support overall health and well-being.
How long does an outbreak last?
HS doesn't have "outbreaks." It is a chronic condition. However, affected individuals can experience hemolytic crises, which are periods of increased red blood cell destruction. These crises can last for several days to a few weeks. The duration and severity of a hemolytic crisis can vary depending on the individual and the underlying cause.
How is it diagnosed?
Complete blood count (CBC): Shows anemia (low red blood cell count), increased reticulocyte count (immature red blood cells), and often an increased mean corpuscular hemoglobin concentration (MCHC).
Peripheral blood smear: Microscopic examination of blood cells reveals spherocytes (sphere-shaped red blood cells).
Direct antiglobulin test (DAT or Coombs test): This test is usually negative in HS, helping to differentiate it from autoimmune hemolytic anemia.
Osmotic fragility test: Measures the ability of red blood cells to withstand hypotonic solutions. Spherocytes are more fragile and lyse (break apart) more readily.
EMA (Eosin-5-Maleimide) binding test: A flow cytometry-based test that measures the amount of EMA dye that binds to red blood cell membrane proteins. Reduced EMA binding is characteristic of HS.
Genetic testing: Can identify specific gene mutations associated with HS. This is not always necessary for diagnosis, but can be helpful in confirming the diagnosis or identifying the specific type of HS.
Timeline of Symptoms
9. Timeline of symptoms HS is often diagnosed in childhood, but milder cases may not be detected until adulthood.
Infancy/Childhood: Jaundice, anemia, splenomegaly, failure to thrive (in severe cases). Gallstones can develop even in childhood.
Adolescence/Adulthood: Symptoms may persist from childhood or present for the first time. Anemia, jaundice, splenomegaly, gallstones, fatigue. Hemolytic crises can occur throughout life. The severity and progression of symptoms vary widely among individuals.
Important Considerations
Splenectomy: Splenectomy (surgical removal of the spleen) is a common treatment option for severe HS. While it can significantly reduce hemolysis and improve anemia, it increases the risk of infections, particularly with encapsulated bacteria. Individuals who undergo splenectomy require lifelong antibiotic prophylaxis and vaccinations.
Gallstones: Gallstones are a common complication of HS and may require surgical removal (cholecystectomy).
Pregnancy: Women with HS should be monitored closely during pregnancy due to the increased risk of anemia and other complications.
Family screening: Screening of family members is important to identify other affected individuals, who may benefit from early diagnosis and management.
Individualized management: The management of HS should be individualized based on the severity of the disease, the presence of complications, and the patient's overall health.