Mediterranean Anemia-Thalassemia - PowerPoint Presentation

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Mediterranean Anemia-Thalassemia

Kakavoulis

Nikolaos

Patras Ioannis

What is

Thalassaemia

?

Thalassaemia is a group of inherited disorders of hemoglobin synthesis characterized by reduced or absence of one or more of the globin chains of adult hemoglobin . Genetically, it is autosomal recessive blood disease. The name is derived from the Greek words Θάλασσα= Sea" and ”Αίμια= Blood" in reference to anemia of the sea.

Demographics: Thalassemia

Found most frequently in the Mediterranean, Africa, Western and Southeast Asia, India and Burma

15%

of the greek population have the ‘’T’’ gene.

There are two basic groups of

thalassaemia

.

Alpha (  )ThalassaemiaBeta (  )ThalassaemiaGeneticTypes of Thalassaemia :

Normal Human

Haemoglobins

Haemoglobin

Structural formula

Adult

Hb-A



2



2

97%

Hb-A

2



2



2

1.5-3.2%

Fetal (And 1% in adults)

Hb

-F



2



2

0.5-1%

Embryonic

Hb-Gower 1



2



2

Hb-Gower 2



2



2

Hb-Portland



2



2

Chromosomes

β

Thalassemia: deficient/absent beta subunits

Commonly found in Mediterranean, Middle East, Asia, and Africa

Three types:MinorIntermediaMajor (Cooley anemia)May be asymptomatic at birth as HbF functionsβ Thalassemia



β

Thalassemia minor (trait)

asymptomatic microcytosisminor anemiaβ Thalassemia intermediasymptoms similar to Cooley Anemia but less severeβ Thalassemia major (Cooley Anemia)most severe form moderate to severe anemiaintramedullary hemolysis (RBC die before full development)peripheral hemolysis &

splenomegaly

skeletal abnormalities (overcompensation by bone marrow)

increased risk of thromboses

pulmonary hypertension

&

heart failure

Clinical Outcomes of

β

-

Thalassemia

Disturbance of ratio between

α

& non-α

globin chain synthesis then absence or decrease production of one or more globin chainsFormation of abnormal Hb structuresIneffective erythropoiesisExcessive RBCs DestructionIron OverloadExtra-medullary hematopoiesis Increased HbF expressionPathophysiology

Thalassaemia

Minor :

Usually no signs or symptoms

except for a mild anemia.Thalassaemia Major : 1. Paleness, Jaundice or yellow coloured skin. 2. Growth retardation. 3. Bony abnormalities specially of the facial bones. 4. Enlarged spleen and liver.Signs & Symptoms

Thalassemia minor:

Haemoglobin

:

Haemoglobin level is usually normal or mildly reduced. Peripheral blood film : Hypochromia and Microcytosis (similar to Iron Deficiency Anemia).MCV< 75 fl, RDW < 14%.Reticulocyte Count increasesDecrease Osmotic FragilityHaemoglobin electrophoresis

Laboratory Diagnosis

Globin Chain Testing - determines ratio of globin chains being produced.

DNA Analysis - Determine specific defect at molecular DNA level.

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Other Special Procedures

If Untreated



thalassemia

Major : Death in first or second decade of lifeIntermedia: variable life spanMinor/Minima: Normal life spanCourse and treatment of thalassaemia

Trait – no treatment

required

Intermedia

Major (Cooley anemia)Regular folate supplementationRBC transfusion (Splenectomy may decrease need for transfusions)to maintain [Hgb] ~9-10g/dLBlood transfusions  iron accumulation  iron overloadIron chelators (diferroxamin)Treatment for β Thalassemia

Raising awareness for more frequent blood donations, since patients with

β

-thalasseamia require frequent transfusions

8th of May: Thalassemia awareness day.Suggestions for encountering the disease in a more efficient way

http://www.mayoclinic.com/health/thalassemia/DS00905/DSECTION=treatments%2Dand%

2Ddrugs

http://www.nlm.nih.gov/medlineplus/ency/article/000587.

htmhttp://www.lpch.org/DiseaseHealthInfo/HealthLibrary/hematology/thalbeta.htmlhttp://www.nhlbi.nih.gov/health/health-topics/topics/thalassemia/References