Access over 20 million homework & study documents

Thalassemias are genetic disorders in globin chain

Content type
User Generated
Type
Study Guide
Rating
Showing Page:
1/75
CASE REPORT
Presenter : Sasikala B.
Yeoh Shu TIng
Day/Date : Wednesday, 28
th
of August 2013
Supervisor : dr. Tina Christina. L. Tobing , Sp.A(K)
CHAPTER I
INTRODUCTION
1.1. Background
The term “thalassemia” is derived from the Greek words “Thalassa” (sea)
and “Haema” (blood) and refers to disorders associated with defective synthesis
of alpha- or beta-globin subunits of hemoglobin (Hb)A(alpha2; beta2), inherited
as pathologic alleles of one or more of the globin genes located on chromosomes
11 (beta) and 16 (alpha). More than 200 deletions or point mutations that impair
transcription, processing, or translation of _- or _-globin mRNA have been
identified. The clinical manifestations are diverse, ranging from absence of
symptoms to profound fatal anemias in utero, or, if untreated, in early childhood.
Thalassemias are genetic disorders in globin chain production, inherited
autosomal recessive blood disease. In thalassemia, the genetic defect results in
reduced rate of synthesis of one of the globin chains that make up hemoglobin.
Reduced synthesis of one of the globin chains causes the formation of abnormal
hemoglobin molecules, and this in turn causes the anemia which is the
characteristic presenting symptom of the thalassemias.1,2
Thalassemia was first defined in 1925 when Dr. Thomas B. Cooley
described five young children with severe anemia, splenomegaly, and unusual
bone abnormalities and called the disorder erythroblastic or Mediterranean anemia
because of circulating nucleated red blood cells and because all of his patients
were of Italian or Greek ethnicity. In 1932 Whipple and Bradford coined the term
thalassemia from the Greek word thalassa, which means the sea (Mediterranean)
to describe this entity. Somewhat later, a mild microcytic anemia was described in
families of Cooley anemia patients, and it was soon realized that this disorder was
caused by heterozygous inheritance of abnormal genes that, when homozygous,
produced severe Cooley anemia.2,3
In Europe, Riette described Italian children with unexplained mild
hypochromic and microcytic anemia in the same year Cooley reported the severe
form of anemia later named after him. In addition, Wintrobe and coworkers in the
United States reported a mild anemia in both parents of a child with Cooley
anemia. This anemia was similar to the one that Riette described in Italy. Only
then was Cooley's severe anemia recognized as the homozygous form of the mild

Sign up to view the full document!

lock_open Sign Up
Showing Page:
2/75
hypochromic and microcytic anemia that Riette and Wintrobe described. This
severe form was then labeled as thalassemia major and the mild form as
thalassemia minor. These initial patients are now recognized to have been
afflicted with β thalassemia. In the following few years, different types of
thalassemia that involved polypeptide chains other than β chains were recognized
and described in detail. In recent years, the molecular biology and genetics of the
thalassemia syndromes have been described in detail, revealing the wide range of
mutations encountered in each type of thalassemia.2,4
Pericardial effusion is a common finding in everyday clinical practice. The
first challenge to the clinician is to try to establish an etiologic diagnosis.
Sometimes, the pericardial effusion can be easily related to a known underlying
disease, such as acute myocardial infarction, cardiac surgery, end-stage renal
disease or widespread metastatic neoplasm. When no obvious cause is apparent,
some clinical findings can be useful to establish a diagnosis of probability.
The presence of acute inflammatory signs (chest pain, fever, pericardial
friction rub) is predictive for acute idiopathic pericarditis irrespective of the size
of the effusion or the presence or absence of tamponade. Severe effusion with
absence of inflammatory signs and absence of tamponade is predictive for chronic
idiopathic pericardial effusion, and tamponade without inflammatory signs for
neoplastic pericardial effusion. Epidemiologic considerations are very important,
as in developed countries acute idiopathic pericarditis and idiopathic pericardial
effusion are the most common etiologies, but in some underdeveloped geographic
areas tuberculous pericarditis is the leading cause of pericardial effusion. The
second point is the evaluation of the hemodynamic compromise caused by
pericardial fluid. Cardiac tamponade is not an “all or none” phenomenon, but a
syndrome with a continuum of severity ranging from an asymptomatic elevation
of intrapericardial pressure detectable only through hemodynamic methods to a
clinical tamponade recognized by the presence of dyspnea, tachycardia, jugular
venous distension, pulsus paradoxus and in the more severe cases arterial
hypotension and shock. In the middle, echocardiographic tamponade is
recognized by the presence of cardiac chamber collapses and characteristic
alterations in respiratory variations of mitral and tricuspid flow. Medical treatment

Sign up to view the full document!

lock_open Sign Up
Showing Page:
3/75

Sign up to view the full document!

lock_open Sign Up
End of Preview - Want to read all 75 pages?
Access Now
Unformatted Attachment Preview
CASE REPORT Presenter : Sasikala B. Yeoh Shu TIng Day/Date : Wednesday, 28th of August 2013 Supervisor : dr. Tina Christina. L. Tobing , Sp.A(K) CHAPTER I INTRODUCTION 1.1. Background The term “thalassemia” is derived from the Greek words “Thalassa” (sea) and “Haema” (blood) and refers to disorders associated with defective synthesis of alpha- or beta-globin subunits of hemoglobin (Hb)A(alpha2; beta2), inherited as pathologic alleles of one or more of the globin genes located on chromosomes 11 (beta) and 16 (alpha). More than 200 deletions or point mutations that impair transcription, processing, or translation of _- or _-globin mRNA have been identified. The clinical manifestations are diverse, ranging from absence of symptoms to profound fatal anemias in utero, or, if untreated, in early childhood. Thalassemias are genetic disorders in globin chain production, inherited autosomal recessive blood disease. In thalassemia, the genetic defect results in reduced rate of synthesis of one of the globin chains that make up hemoglobin. Reduced synthesis of one of the globin chains causes the formation of abnormal hemoglobin molecules, and this in turn causes the anemia which is the characteristic presenting symptom of the thalassemias.1,2 Thalassemia was first defined in 1925 when Dr. Thomas B. Cooley described five young children with severe anemia, splenomegaly, and unusual bone abnormalities and called the disorder erythroblastic or Mediterranean a ...
Purchase document to see full attachment
User generated content is uploaded by users for the purposes of learning and should be used following Studypool's honor code & terms of service.

Anonymous
I was struggling with this subject, and this helped me a ton!

Studypool
4.7
Trustpilot
4.5
Sitejabber
4.4

Similar Documents