Sickle Cell Anemia1

8/12/2019 Sickle Cell Anemia1

1/40

SICKLE CELL ANEMIA

Yousef Ali

Mohamed abu-

elheja

Group: 1346


2/40

Structure of Hemoglobin

Hb is conjugated protein moleculeconsists of two pairs of polypeptidechain. (alpha & bate)

Each globin chain bears a hem groupwhose central iron atom is the site towhich O2 attaches to hemoglobin.

Molecular weight of Hb is 64000.


3/40


4/40

HISTORY of sickle cellanemia In the year 1904 cardiologist and

professor of medicine James BHerrick found peculiar elongated cells

in blood of a 20 years old dentalstudent who was suffering fromanemia.

Veron Mason in 1922 named SICKLECELL ANEMIA.


5/40

HISTORY of sickle cellanemia Linus Pauling in 1940 demonstrated

that sickling occurs as a result ofabnormality in hemoglobin molecule.

Sickle cell disease is the first geneticdisorder whose molecular basis wasknown.

June 19this celebrated as WorldSickle Cell Day.


6/40


7/40

What is Sickle Cell Anemia?

A serious condition in which red bloodcells can become sickle-shaped

Normal red blood cells are smooth and

round. They move easily through bloodvessels to carry oxygen to all parts ofthe body.

Sickle-shaped cells dont movethrough blood. Theyre stiff and stickyand tend to form clumps and get stuckin blood vessels.


8/40

What is Sickle Cell Anemia?

The clumps of sickle cell block bloodflow in the blood vessels that lead tothe limbs and organs. Blocked blood

vessel can cause pain, seriousinfection, and organ damage.


9/40

PATHOPHYSIOLOGY

Sickle cell anemia is a autosomalrecessive genetic disease that resultsfrom the substitution of Valine from

Glutamic acid in position 6 of betaglobin gene leading to production ofdefective form of hemoglobin (Hb S).

Hb S is structurally defectivehemoglobin.


10/40

Normal and Sickled Red BloodCells

in Blood Vessels

Figure A shows normal red blood cellsflowing freely in a blood vessel. The insetimage shows a cross-section of a normal

red blood cell with normal hemoglobin.

Figure B shows abnormal, sickled redblood cells clumping and blocking theblood flow in a blood vessel. The inset

image shows a cross-section of a sickledred blood cell with abnormal strands of

hemoglobin.


11/40

Normal vs. Sickle

Hemoglobin

Normal

disc-Shaped

soft(like a bag of

jelly) easily flow through

small blood vessels

lives for 120 days

Sickle

sickle-Shaped

hard (like a piece

of wood)often get stuck in

small blood vessels

lives for 20 days orless


12/40

Why Anemia?

Anemiais a condition in which apersons blood has a lower than

normal number of red blood cells, or

the red blood cells dont have enoughhemoglobin. Hemoglobin is an iron-rich protein that gives blood its red

color and carries oxygen from thelungs to the rest of the body.


13/40

Why Anemia?

Normal red blood cells last about 120 days inthe blood stream and then die. Their mainrole is to carry oxygen, but, they also removecarbon dioxide (a waste product) from cells

and carry it to the lungs to be exhaled. In sickle cell anemia, a lower-than-normal

number of red blood cells occurs becausesickle cells dont last very long. Sickle cells

die faster than normal red blood cells, usuallyafter only about 10 to 20 days. The bonemarrow cant make new red blood cells fastenough to replace the dying ones. The resultis anemia.


14/40

Who Is At Risk?

The disease originated in at least 4 places in Africa,Mediterranean countries (such as Turkey, Greece, andItaly), and in the Indian/Saudi Arabian subcontinent. Itexists in all countries of Africa and in areas whereAfricans have migrated.

It is most common in West and Central Africa where asmany as 25% of the people have sickle cell trait and 1-2% of all babies are born with a form of the disease.

In the United States with an estimated population of

over 270 million, about 1,000 babies are born withsickle cell disease each year.

In contrast, Nigeria, with an estimated 1997 populationof 90 million, 45,000-90,000 babies with sickle celldisease are born each year.


15/40

Who is at Risk?

United States, sickle cell anemiaaffects about 70,000 people.

Mainly affects African Americans,with the condition occurring in

about 1 in every 500 AfricanAmerican births.

Hispanic Americans also areaffected; the condition occurs in 1out of every 1,000 to 1,400

Hispanic American births. About 2 million Americans have

sickle cell trait. About 1 in 12African Americans has sickle cell

trait.


16/40


17/40

Who is at Risk?

The transatlantic slave trade was largelyresponsible for introducing the sickle cellgene into the Americas and the Caribbean.However, sickle cell disease had already

spread from Africa to Southern Europe by thetime of the slave trade, so it is present inPortuguese, Spaniards, French Corsicans,Sardinians, Sicilians, mainland Italians,Greeks, Turks and Cypriots. Sickle celldisease appears in most of the Near andMiddle East countries including Lebanon,Israel, Saudi Arabia, Kuwait and Yemen.


18/40

Who is at Risk?

The condition has also been reported in Indiaand Sri Lanka. Sickle cell disease is aninternational health problem and truly a globalchallenge.

All these countries must work together tosolve the problem and find effectivetreatments and ultimately a cure. Theknowledge and expertise in the managementof sickle cell disease acquired in thetechnologically advanced countries must beshared with the less developed countrieswhere patients die at alarming rates.


19/40


20/40

Ri k F t f Si kl C ll


21/40

Risk Factors for Sickle Cell

Anemia

Predisposing factors for the incidence ofsickle cell syndromes include: Family History - As this condition cannot be

acquired, family history is the most importantrisk factor in the development of a sickle cellsyndrome.

Race - The condition is more common innegro populations.

Local prevalence of malaria- As sickle cell

disease protects against the development ofmalaria, the process of natural selection hasincreased the prevalence of sickle celldisease to 30% in some regions.


22/40

Complication of Sickle CellAnemia Hand-Food

Syndrome

Splenic Crisis

InfectionsAcute Chest

Syndrome

Delayed growth

and puberty inchildren

Stroke

Eye problem

Priapism Gallstone

Ulcers on the legs

Pulmonary ArterialHypertension (Highblood pressure)

Multiple Organ

Failure


23/40

Smoothed hazard rates of infarctive and

hemorrhagic stroke in SS patients by age. ()Infarctive stroke; (---) hemorrhagic stroke.


24/40

DIAGNOSIS

The most widely used blood test forsickle cell disease and trait is thehemoglobin electrophoresis. A blood

sample is placed in an electric field onfilter paper and the differenthemoglobins travel at different speeds

to the negative pole: HbAA -Normal,Hb AS - Trait, Hb SS - Disease, HbSC


25/40

Diagnosis - Blood Smear

Sickle red cells


26/40

Treatments Effective treatments are available

to help relieve the symptoms andcomplications of sickle cell anemia,but in most cases theres no cure.

The goal is to relieve the pain;prevent infections, eye damage,

strokes and control complications ifthey occur.

Pain medicine: acetaminophen,nonsteroidal anti-inflammatorydrugs (NSAIDs), and narcotics

such as meperidine, morphine,oxycodone, and etc. Heating pads Hydroxyurea, Folic Acid Blood Transfusions


27/40

New Treatments andMedicines Bone marrow transplants Gene therapy

New medicine

Butyric acid. This is a food additive that mayincrease normal hemoglobin in the blood.

Clotrimazole. This is used now to treat fungusinfections. This medicine helps prevent the loss ofwater from a red blood cell and can keep the cell from

turning into a sickle cell. Nitric oxide. This may make sickle cells less sticky

and keep blood vessels open. People with sickle cellanemia have low levels of nitric acid in their blood.

Distribution of Pain Rates among Patients with Sickle


28/40

Distribution of Pain Rates among Patients with Sickle

Syndromes.

r denotes the number of episodes of pain per patient-year, SSsickle cell anemia, SC hemoglobin SC disease, S+sickle+-

thalassemia, and S0sickle 0-thalassemia

Age Specific Pain Rates (Episodes per Patient Year)


29/40

Age-Specific Pain Rates (Episodes per Patient-Year)

among Male (Dashed Line) and Female (Solid Line)

Patients with Sickle Cell Anemia.


30/40

Sickle Cell DISEASE NationalStatistics Nationally, it is estimated that more than80,000 Americans are living with sickle

cell disease, according to the NationalInstitute of Health (NIH, 2007).

1 in 375 African Americans are living withsickle cell disease.

1 in 1100 to 1400 Hispanics are livingwith sickle cell disease.


31/40

Sickle Cell DISEASE NationalStatistics 1 in 58,000 Caucasians are living with

sickle cell disease.

Sickle cell trait, the healthy carrier state

for sickle cell disease, occurs inapproximately 1 in 12, or 8 percent ofAfrican Americans.

The sickle gene is also found in peoplefrom South and Central America, theMiddle East and the Mediterranean.


32/40

Death and mortality statistics forSickle Cell Anemia Deaths from Sickle Cell Anemia: 501

deaths (NHLBI 1999)

Death rate extrapolations for USA for

Sickle Cell Anemia: 500 per year, 41 permonth, 9 per week, 1 per day, 0 per hour,0 per minute, 0 per second. Note: thisextrapolation calculation uses the deaths

statistic: 501 deaths (NHLBI 1999)


33/40


34/40

Survival of Patients with Sickle Cell Anemia (=20 Years Old


35/40

Survival of Patients with Sickle Cell Anemia (=20 Years Oldat Entry) Who Had Different Pain Rates.


36/40

The Cost to Society

Sickle cell disease is a major publichealth concern. From 1989 through1993, there were an average of

75,000 hospitalizations due to sicklecell disease in the United States,costing approximately $475 million


37/40


38/40


39/40

Prevention

Identify what can triggerthe Crisis such as stress,avoid extremes of heat andcold weather, dont travel

airplane that is not cabinpressurized

Maintain healthy lifestylehabits

Eating healthy

Avoid dehydrationExercise regularly

Get enough sleep and rest

Avoid alcohol and dont smoke

Regular medical checkups

and treatment areimportant


40/40

Sickle Cell Anemia1

Documents