2. What is Sickle Cell Anemia?
Sickle cell disease is an inherited
disorder that affects red blood cells.
Sickle Cell Anemia is a genetic disorder
that slightly alters the structure of
hemoglobin, the oxygen carrying protein
in red blood cells. This modefiedfied
hemoglobin, when not carrying oxygen,
tends to clump with other deoxygenated
hemoglobin and causing blood to cut
throughout the body.
3. Who Is At Risk for Sickle Cell Anemia?
Sickle cell disease affects more
than 72,000 Americans.
Africa, South or Central America
(especially Panama), Caribbean
islands, Mediterranean countries
(such as Turkey, Greece, and
Italy), India, and Saudi Arabia.
4.
5. How this Trait is Inherited
Sickle cell anemia is an inherited, lifelong
disease. People who have the disease are
born with it. They inherit two copies of the
sickle cell gene—one from each parent.
If you inherit only one copy of the sickle
cell gene (from one parent), you will not
have sickle cell anemia. Instead, you will
have sickle cell trait.
People who have sickle cell trait usually
have no symptoms and lead normal lives.
However, they can pass the sickle cell
gene to their children.
6. Signs and Symptoms
• The most common symptom of
anemia is fatigue (feeling tired or
weak). Other signs and symptoms of
anemia include:
• Shortness of breath
• Dizziness
• Headache
• Coldness in the hands and feet
• Pale skin
• Chest pain
7. Signs and Symptoms Related to Pain
Sudden pain throughout the body is a common
symptom of sickle cell anemia. This pain is called
a "sickle cell crisis." Sickle cell crises often affect
the bones, lungs, abdomen, and joints.
A sickle cell crisis occurs when sickled red blood
cells form clumps in the bloodstream. (Other cells
also may play a role in this clumping process.)
These clumps of cells block blood flow through
the small blood vessels in the limbs and organs.
This can cause pain and organ damage.
8. Complications
Hand-Foot Syndrome
Splenic Crisis
- The spleen is an organ in the abdomen. Normally, it
filters out abnormal red blood cells and helps fight
infection. In some cases, the spleen may trap cells
that should be in the bloodstream. This causes the
spleen to grow large and leads to anemia.
Acute Chest Syndrome
- a life-threatening condition linked to sickle cell
anemia. It’s similar to pneumonia. The condition is
caused by an infection or sickle cells trapped in the
lungs.
9. Complications
Priapism
- Males who have sickle cell anemia may
have painful and unwanted erections. It
happens because the sickle cells block blood
flow out of an erect penis. Over time,
priapism can damage the penis and lead to
impotence.
Multiple Organ Failure
- Multiple organ failure is rare, but serious. It
happens if you have a sickle cell crisis that
causes two out of three major organs (lungs,
liver, or kidney) to fail.
PRIAPU
S
10. How Is Sickle Cell Anemia Treated?
Bone Marrow Transplant
Gene Therapy
• Researchers are studying several new medicines for sickle cell
anemia. These include:
• Butyric acid. This is a food additive that may increase normal
hemoglobin in the blood.
• Nitric oxide. This medicine may make sickle cells less sticky and
keep blood vessels open. People who have sickle cell anemia have
low levels of nitric oxide in their blood.
• Decitadine. This medicine increases hemoglobin F levels (this type
of hemoglobin carries more oxygen). It may be a good choice
instead of hydroxyurea.
11. Prevention
You can’t prevent sickle cell anemia, because
it’s an inherited disease.
If a person is born with it, steps should be
taken to reduce complications.
Genetic Counseling should be considered.
A counselor can explain the risk of having a
child who has the disease and can help explain
the choices that are available.
14. INTRODUCTION
G6PD deficiency is the most common disease producing
enzyme abnormalities in humans, affecting more than 200
million individuals worldwide.
The highest prevalence in the Middle East, tropical Africa
& Asia.
G6PD Deficiency is caused by 400 different mutations in
gene coding for G6PD, only few of them causes the
clinical symptoms of the disease.
15. G6PD DEFICIENCY
G6PD is an metabolic enzyme is
involved in pentose phosphate pathway,
especially important in red blood cell
metabolism
It also protects red blood cells from the
effects of potentially harmful molecules
called REACTIVE OXYGEN SPECIES
16. G6PD Deficiency Mode of inheritance
•
• It is X- linked recessive genetic disorder (gene is carried on X-chromosome).
• The gene is present on the X chromosome
• The inheritance follows specific pattern:
Males have one X chromosome
So, they will be diseased if they have the affected gene (xY)
Females have 2 X chromosomes
may be homozygous or heterozygous
Homozygous: are diseased (xx)
Heterozygous: are not diseased BUT: carriers (Xx)
& can transfer the disease to their sons
17. Male to Female ratio
Male cases are overrepresented compared with female cases.
Males are hemizygous for the G6PD gene; therefore the expression is either
normal or deficient.
In contrast, in females who have two copies of the gene on each
chromosome, the gene expression can be normal or heterozygous.
Homozygous inheritance in females can occur; whereas, heterozygous
females have genetic mosaicism secondary to X-chromosome inactivation
and can have similar manifestation as male neonates.
18. Who Is At Risk for Sickle Cell Anemia?
Most common in African-American males.
Many African-American females are carriers of G6PD
deficiency, meaning they can pass the gene for the
deficiency to their children but do not have symptoms;
only a few are actually affected by G6PD deficiency.
People of Mediterranean heritage, including Italians,
Greeks, Arabs, and Sephardic Jews, also are commonly
affected.
The severity of G6PD deficiency varies among these
groups — it tends to be milder in African-Americans and
more severe in people of Mediterranean descent.
19.
20. X-LINKED RECESSIVE HEREDITARY
A mode of inheritance in which a mutation in a gene on
the X chromosome causes the phenotype to be expressed
in males who are hemizygous.
Male = XY ( Hemizygous)
Female = XX (Homozygous)
21.
22. What is favism?
G6PDH is closely linked to favism.
Favism is formally defined as hemolytic response
to the consumption of broad beans
Favism is disorder characterized by hemolytic
reaction to the consumption of broad beans
All individual with favism show G6PD deficiency
However not all individuals with G6PD
deficiency show favism
23. PATIENTS OF G6PD
DEFICIENCY Most indivudual with G6PD deficiency are
asymtomatic
ASYMPTOMATIC- A disease is considered to be
asymptomatic if a patient is a carrier for a disease or
infection but experiences no symptoms.
Asymptomatic infections are also called subclinical
infections.(CLINICALLY SILENT)
SYMPTOMATIC patients are almost exclusively
male, due to the X-linked pattern of inheritence.
But female carriers can be clinically affected due to
unfavourable lyonization, where random
inactivation of an X-CHROMOSOMES.
24. Symptoms of G6PD Deficiency
paleness (in darker-skinned children paleness is
sometimes best seen in the mouth, especially on
the lips or tongue)
extreme tiredness
rapid heartbeat
rapid breathing or shortness of breath
jaundice, or yellowing of the skin and eyes,
particularly in newborns
an enlarged spleen
dark, tea-colored urine
25. Why does G6PD deficiency occur more often in
certain groups of people?
It is known that Africa and the Mediterranean basin are high-risk
areas for the infectious disease malaria.
Researchers have found evidence that the parasite that causes this
disease does not survive well in G6PD-deficient cells.
So they believe that the deficiency may have developed as a
protection against malaria.
Generally this disease can be also caused by blood tranfusion.
26. Management of G6PD Deficiency
Since G6PD deficiency is a genetic disorder, there is no cure but
the main treatment is avoidance of oxidative stressors.
G6PD deficiency is prevented by avoiding fava beans, oxidant
drug, oxidant chemicals and other stressors.
In the acute phase of hemolysis, blood transfusions might be
necessary.
