Thalassemia

Thalassemia

Thalassemia

Thalassemias are a heterogeneous group of hereditary blood disorders characterized by faulty globin chain synthesis resulting in defective hemoglobin, which can lead to anemia

Thalassemia provides partial resistance against malaria.

Beta thalassemia

Clinical features

Minor variant (heterozygous): unremarkable symptoms (low risk of hemolysis, rarely splenomegaly)

Major variant (homozygous) Severe hemolytic anemia, Hepatosplenomegaly ,Growth retardation ,Skeletal deformities (high forehead, prominent zygomatic bones, and maxilla)

Alpha thalassemia

most commonly seen in people of Asian and African descent

Clinical features

Silent carrier: asymptomatic

Alpha thalassemia trait: mild hemolytic anemia with normal RBC and RDW

Hemoglobin H disease

Jaundice and anemia at birth

Chronic hemolytic anemia which may require transfusions

Hb-Bart's hydrops fetalis syndrome (most severe variant of alpha thalassemia)

Intrauterine ascites and hydrops fetalis, severe hepatosplenomegaly, and often cardiac and skeletal anomalies

Incompatible with life (death in utero or shortly after birth)

Diagnostics

Microcytic hypochromic anemia

Blood smear: target cells , teardrop cells

Bone marrow biopsy: reactive hyperplasia

Confirmatory tests

Hb-electrophoresis Alpha thalassemia can usually only be detected if ≥ 3 alleles are defective.

DNA analysis: to test for alpha thalassemia minor and minima (< 3 alleles defective)

Skeletal deformities -high forehead, prominent zygomatic bones and maxilla can be seen on all imaging modalities.

X-ray: hair-on-end (“crew cut”) sign

Related Questions HAEMATOLOGY

Thalassemia

Thalassemias are a heterogeneous group of hereditary blood disorders characterized by faulty globin chain synthesis resulting in defective hemoglobin, which can lead to anemia

Thalassemia provides partial resistance against malaria.

Beta thalassemia

Clinical features

Minor variant (heterozygous): unremarkable symptoms (low risk of hemolysis, rarely splenomegaly)

Major variant (homozygous) Severe hemolytic anemia, Hepatosplenomegaly ,Growth retardation ,Skeletal deformities (high forehead, prominent zygomatic bones, and maxilla)

Alpha thalassemia

most commonly seen in people of Asian and African descent

Clinical features

Silent carrier: asymptomatic

Alpha thalassemia trait: mild hemolytic anemia with normal RBC and RDW

Hemoglobin H disease

Jaundice and anemia at birth

Chronic hemolytic anemia which may require transfusions

Hb-Bart's hydrops fetalis syndrome (most severe variant of alpha thalassemia)

Intrauterine ascites and hydrops fetalis, severe hepatosplenomegaly, and often cardiac and skeletal anomalies

Incompatible with life (death in utero or shortly after birth)

Diagnostics

Microcytic hypochromic anemia

Blood smear: target cells , teardrop cells

Bone marrow biopsy: reactive hyperplasia

Confirmatory tests

Hb-electrophoresis Alpha thalassemia can usually only be detected if ≥ 3 alleles are defective.

DNA analysis: to test for alpha thalassemia minor and minima (< 3 alleles defective)

Skeletal deformities -high forehead, prominent zygomatic bones and maxilla can be seen on all imaging modalities.

X-ray: hair-on-end (“crew cut”) sign