thalassemia

 Thalassemia

Thalassemia is inherited disease. It is autosomal recessive disorder, characterized by absence or decrease synthesis of one or more globin chains of hemoglobin, result in inadequate hemoglobin production.

Blood disorder involving lower than normal amounts of oxygen- carrying protein inside the RBC and make abnormal form of hemoglobin.

Types of Thalassemia 

Hemoglobin consist of 2 alpha protein and 2 beta protein.

Thalassemia occurs when defect in gene that control production of protein chains.

1. According to defect of genes

Two types;

1. Alpha thalassemia

Gene related to apha globin protein are missing or changed (mutated).

3. Beta thalassemia

Gene defect affect production of beta globin protein.

Beta thalassemia is more common.

2. According to severity

1. Thalassemia minor

Associated with decreased beta chain synthesis. 

Heterozygous form of disease i.e defective gene received from one parents.

Usually asymptomatic, person with thalassemia minor disease are carriers of disease.

2.Thalassemia major

Cause severe anaemia 

Associated with little or no capacity to produce beta chain of hemoglobin.

Also known as Cooley's anaemia/ Mediterranean anaemia.

Homozygous form of disease i.e defected gene received from both parents.

Pathophysiology of thalassemia

Disturbance in production of alpha globin

Mutation in gene in alpha globin, mutation in coding sequence of alpha globin, gene cluster hemoglobin is impaired.

(Gene for alpha globin located on chromosome 16; 14 gene present)

(Gene for beta globin located on chromosome 11; 5 gene present)

Protein synthesis inhibited

Decrease in hemoglobin synthesis.

Clinical manifestations

Diagnosis of thalassemia major between 10-12 months age; 1st year of life.

1. Absent or defective synthesis of hemoglobin.

2. Decreased life span of RBCs

3. Inadequate structureed RBCs

Rapid breakdown of RBC,

Leading to release of iron

Excessive amount of insoluble iron "hemosiderin" deposited in tissue.

Leading to hemosiderosis (excessive iron storage in tissue without tissue damage) and hemochromatosis (excessive iron stroage in tissue which result in tissue damage)

4. Most severe form of alpha thalassemia major cause stillbirth.

5. Anaemia

6. Failure to thrive

7. Inability to bone marrow to produce sufficient of normal RBCs lead to;

1. Weakness

2. Excercise tolerance

3. Anorexia

4. Headache

5. Precordial pain; chest pain

8. Rapid hemolysis affects;

1. Skin;

Jaundice

Excessive iron released from rapid hemolysis deposited under skin; brown and bronze discoloration of skin.

2. Heart

Hemochromatosis; causes fibrotic changes in myocardium

3. Spleen

Rapid destruction of RBCs; Spleenomegaly, abdominal distension

Hemochromatosis; causes fibrotic change in spleen.

4. Liver

Hemochromatosis lead to fibrosis of liver cells cause liver cirrhosis.

5. Pancreas

Hemochromatosis changes of Fibrosis of pancreas.

6. Endocrine

Delay or absent sexual maturation.

7. Skeletal system

Hyperplasia in bone marrow; skeletal deformities.

Deformities in face.

8. Iron overload

9. Dark urine

Diagnostic Evaluation

1. Hemoglobin estimation

2. Complete blood count

3. Peripheral blood smear

4. Bone marrow examination

Hemosiderin deposit seen in bone marrow.

Hyperplasia of bone marrow

5. Serum bilirubin

6. Serum iron

7. Radiological studies;

X ray

8. Mutation analysis

Detect apha thalassemia

9. Aminocentesis

10. Molecular diagnostic test

11. Osmotic fragility test

Determine red blood cells prone to break easily.

Exposure to hypertonic solution; repture more easily

Management

1. Supportive therapy

Correct anemia, target hemoglobin (Hb) level 9-10 mg/dl

2. Transfusion therapy

Not take iron supplements during blood transfusion. 

3. Chelation therapy

Due to multiple blood transfusion administration (10-15 blood transfusion) increases level of iron in blood.

Iron chelation agent; deferoxamine (dose; 20mg/kg/day) to prevent iron overload, by removing excess iron from body.

Desferrioxamin; iron chelating agent 

Subcutaneously given dose 40- 60mg/kg/day.

Deferiprone is effective oral iron chelating agent (dose; 20mg/day)

4. Spleenectomy

Act as store non-toxic iron; protection body from extra iron.

But with hypersplenism; leading to excessive destruction of erythrocytes and increasing need of frequent blood transfusion which result iron accumulation.

4. Anticoagulant

Administerd before blood transfusion.

5. Bone marrow Transplantation

Nursing Management

1. Taking history infant/child

2. Assess the general condition.

1. Identify the sign and symptoms (early diagnosis).

2. Pedigree chart

3. Preparation of child for diagnostic procedure

4. Care during blood transfusion

5. Manage fluid overload

6. 24 hours urine collection after chelating therapy to estimate amount of iron excreted.

Role of Nurse during Blood Transfusion

1. Before transfusing blood;  Blood grouping cross matching

2. Blood screened for Hepatitis B, C, HIV, malaria, Cytomegalovirus

3. Routine donor screening

4. Observe patient for transfusing reaction;

Chills, itching, rash, headache and back ache.

Incase of Transfusion reaction; stop Transfusion and immediately inform to physician.

5. Monitor vital signs during blood transfusion.

6. Infuse blood slowly to prevent circulatory overload

7. Follow strict aseptic technique

8. Always prewarm blood before blood transfusion

9. Administration of Chelating Therapy

Needto excrete excessive iron.

Chelating agent bind with excessive iron.

Excreted in urine; 

Low iron diet to child.

Food item such as; spinach, apple, grams, juggery avoided.

Vitamin C avoided;  they increase absorption of iron from diet.

10. Prevention of Infection

Aseptic technique;

Blood transfusing

Collection of specimen

Administration of Chelating

Invasive procedure therapy

11. Education and support of parents and child

Psychological support to child.

Understand cause of disease; help to child leading normal life.

Prevention

1. Thalassemia screening of individual

2. Screening during pregnancy

3. Prenatal diagnosis

4. Marital counseling

5. Medical abortion if affected fetus.

6. If two persons have thalassemia minors (carriers) should not marry; children may born with thalassemia major