Hemoglobinopathies
Updates to Article Attributes
A haemoglobinopathy is a genetic disorder which alters the structure of haemoglobin 1. The result is reduced oxygen-carrying capacity of the blood to the tissues, and other sequelae.
Clinical presentation
Clinical presentation varies, is related to hypoxia, and characteristically includes the following:
- claudication
- tachycardia
- dyspnea
- vertigo
- angina
Pathology
- vascular occlusion leading to infarcts
- necrosis
- pathological fracture
- osteomyelitis (100x more likely in sickle cell disease patients) 2
Classification
Types of haemoglobinopathies include the following, with the predominant type of abnormal haemoglobin in bracketsparentheses following the disorder.
- sickle cell disease (HbS)
- sickle cell trait (HbAS)
- sickle cell-haemoglobin C (HbSC)
- sickle cell-thalassemia (HbS and HbA)
-
thalassemia
- alpha thalassemia (deficient alpha-globin chain synthesis)
- beta thalassemia (deficient beta-globin chain synthesis)
- thalassemia major (homozygous) - Cooley anaemia
- thalassemia minor (heterozygous)
- haemoglobin C disease (HbCC)
- haemoglobin C trait (HbAC)
Radiographic features
The radiographic features of hemoglobinopathies vary and some are generallymore specific for specific hemoglobinopathies (e.g. splenic sequestration in sickle cell). Generally, many common radiographic features are related to extramedullary hematopoiesis and infarctions as follows:
-
extramedullary haematopoiesis
- Erlenmeyer flask deformity
- hair-on-end appearance (characteristic, not pathognomonic, of thalassemia)
- rib expansion
- calvarial alterations
- diploic widening
- outer table thinning
- facial bone alterations
- nasal and temporal bone expansion (obliteration of sinuses)
- lateral displacement of orbits (hypertelorism)
- dental displacement
- infarctions
- epiphyseal ischemia (especially in the femoral head)
- growth disturbances
- osseous insufficiency
- haemarthrosis
- hand-foot syndrome (characteristic of sickle cell disease)
-</ul><h5>Classification</h5><p>Types of haemoglobinopathies include the following, with the predominant type of abnormal haemoglobin in brackets following the disorder.</p><ul>- +</ul><h5>Classification</h5><p>Types of haemoglobinopathies include the following, with the predominant type of abnormal haemoglobin in parentheses following the disorder.</p><ul>
-<li><a title="Haemoglobin SC disease" href="/articles/haemoglobin-sc-disease">sickle cell-haemoglobin C (HbSC)</a></li>- +<li><a href="/articles/haemoglobin-sc-disease">sickle cell-haemoglobin C (HbSC)</a></li>
-</ul><h4>Radiographic features</h4><p>The radiographic features of hemoglobinopathies vary and are generally related to extramedullary hematopoiesis and infarctions as follows:</p><ul>- +</ul><h4>Radiographic features</h4><p>The radiographic features of hemoglobinopathies vary and some are more specific for specific hemoglobinopathies (e.g. splenic sequestration in sickle cell). Generally, many common radiographic features are related to extramedullary hematopoiesis and infarctions as follows:</p><ul>