Sickle cell anemia - By Janaki raman

1. SICKLE
CELL
ANAEMIA
BY
Janakiraman.K
29 VZ
th

3.  Hb A1- 97% of adult haemoglobin,
consists of 2 alpha & 2 beta chains.
 Hb A2- Consists of 2 alpha & 2 delta
chains.
 Hb F - 70 – 90% at birth, 25% by 1
month and 5% by 6months of age,
consists of 2 alpha & 2 gamma
chains.

4. 1. Sickle Cell Traits (HbAS) Adequate
amount of normal haemoglobin is
present, they are carriers, do not have
symptoms of sickle cell disorder.
2. Sickle Cell Anemia (HbSS) Most severe form of
disease
3. Haemoglobin C (HbSC)
4. Haemoglobin E (HbSE)
5. Haemoglobin S beta Thalasseamia-This
is a mild form of sickle disorder.

5.  Sickle cell anemia is a autosomal recessive
genetic disease that results from the
substitution of Valine from Glutamic acid in
position 6 of beta globin at chromosome 11
leading to production of defective form of
haemoglobin.(Hb S)
 Hb S is a structurally defective haemoglobin.

6. MEChANISM of SICKLE CELL ANEMIA

8.  Deoxygenation leads to hydrophobic interaction
between adjacent Hb S molecules.
 This leads to hydrophobic polymerization of red cell
membrane
 The red cell cytosol becomes viscous gell as HBs
aggregates form and become needle with continued
deoxygination distortion of RBC into sickle form cells
 Rapid haemolysis
 Decreased elasticity of cell wall of RBC
 Decreased life span 10 – 20 days. From 120 days
 Clogging of RBC in microcirculation

9. • ChroNIC hEMoLySIS
• MICrovASCuLAr
oCCLuSIoNS
• TISSuE dAMAgE

10. SICKLE CELL TrAIT
40% hbS 60% hbA . hbA prEvENTS SICKLINg uNTILL
profouNd hypoxIA
hbf vS hbS
hbf INhIbIT poLyMErISATIoN , No SyMTEMS upTo 6
MoNThS
hErEdITAry pErSISTENT hbf SICKLE CELL dISEASE
LESS SEvErE
hbC vS hbS
IN hbSC hbS 50% + dEhydArTIoN of hbSC INCrEASEd
hbS poLyMErISATIoN CAuSE hbSC dISEASE

11. MCHC
INTrA CELLuLAr dEhydrATIoN INCrErSES MChC fACILITATES SICKLINg
Ph
dECrEASE IN ph INCrEAS dEoxygINATEd hbS AugMENTINg SICKLINg
Transit time of blood cells through micro vascular
bed
ShorT TrANSIT TIME LEAdS To AggrEgATIoN of dEoxygENATEd hbS-
SICKLINg
TrANSIT TIME IS NorMAL IN SpLEEN ANd boNE MArrow So
proMINENTLy AffECTEd
INfLAMEd vESSELS INfLAMEd TISSuE ArE proNE for dECrEASINg
TrANSIT TIME ANd proNE for SICKLINg

13. Genetics
 2
c
o
p
i
e
s
o
f
t
h
e
g
e

14.  Vasooclusive crisis
 Haematological crisis
 Aplastic crisis
 Sequestration crisis
 Infectious crisis
 Autospleenectomy

15.  Obstructed microcirculation leading to ischemic injury to
organ
1. Avascular necrosis
2. Acute chest syndrome
3. Acquired asplenia
4. Splenic sequestration
5. Hand foot syndrome
6. Papillary necrosis in kidneys
7. Hyposthenuria and enuresis
8. Cerebral infarction
9. Skin ulceration
10. Retinal hemorrhage and retinopathy
11. Priaprism

17.  Acute splenic sequestration, pooling of blood
in the engorged spleen
 Aplastic crisis – Seen in patients with parovrus
B-19 infection or folic acid deficiency leading to
decreased marrow erythropoiesis
 Anemia
 Pigmented gallstone
 Jaundice
 Delayed growth

18. AuTINfArCTEd SpLEEN

19. SpLEENIC pAThoLogy

22.  Infectious crisis is due to functional asplenia
and decreased level of serum immunoglobulin
M (IGM) increasing susceptibility to infections.
 Haemophilius influenzae, streptococcus
pneumoniae, mycoplasma pneumoniae, salmonella
typhimurium, staphylococcus aureus, and
escherichia coli are the common causative
microbes.
 Common infections include pneumonia,
bronchitis, pyelonephritis, cystitis,
osteomyelitis, meningitis, and sepsis

23.  CVS-Anemia and vasooclusive phenomena causing
myocardial ischemia and myocardial infarction, repeated
blood transfusion leading to restrictive cardiomyopathy.
 Pulmonary-Acute chest syndrome
 CNS-25% patient have TIA, strokes, cerebral hemorrhage
 Hepato biliary system-Gall stone recurrent abdominal pain,
autosplenectomy
 Urinary system- Haematuria, hyposthenurea and renal
failure
 Ocular complication- Proliferative retinopathy, vitreous
hemorrhage and retinal detachment
 Orthopedic – Hand foot syndrome, avascular necrosis of
hip, osteomyelitis

27. 1. Young infants have recurrent edema of the dorsum of
hands and feet.
2. Infarction of cortex of long bones lead to prominent signs of
local inflammation.
3. Repeated infarction in the joints of large and small bones
lead to abnormal angled digits, malformed and frozen joints,
particularly at the knee and ankle.
4. Chronic leg ulcer is common in adolescent patients.
5. Abdominal examination may reveal splenomegaly if
sequestration is occurring otherwise the spleen is small in
size due to autoinfarction
6. Evidence of cholilethiasis is seen in patients as young as 3
years old.
7. By mid childhood most patients are underweight as
compared to children of their same age and height.

29. 1. There is a higher rate of spontaneous abortion. A
miscarriage may happen up to 25% of the time.
1. There is ahigher rate of babies not surviving to
birth or being stillborn. 8-10% .
1. Birth weight is lower than average.
2. Infection is more common in women with sickle
celldisease during pregnancy, especially
bladder infection.
3. Increased chance of PIH and preeclampsia
4. Increased incidence of PPH.

30. Medical Complications
1. pain episodes 9. kidney damage and
loss of body water in urine
2. strokes
10. painful erections in men
3. increased infections
(priapism)
4. leg ulcers
11. blood blockage in the spleen
5. bone damage or liver (sequestration)
6. yellow eyes or 12. eye damage
jaundice
13. low red blood cell counts
7. early gallstones (anemia)
8. lung blockage 14. delayed growth

31.  Hb-6-8gm%
 Reticulocytes high
 Peripheral smear may show sickle cells
 Features of hyposplenism :Target cells and Howell-
Jolley bodies seen
 Sickle solubility test
 Sickling test with reducing agent Sodium
metabisulphide
 Hb electrophoresis
 High performance liquid chromatography(HPCL)
 WBC may be elevated
 Bilirubin may be elevated
 Urinarary cast may be seen or trace of RBC in urine
 Howell-Jolly bodies

36. 1. Oxygenation
2. Pain Management (NSAID, OPIODS)
3. Hydroxyurea, Folic acid
4. Hydration
5. Blood Transfusion
6. Antibiotics (Penicillin group)
7. Steroids
8. Bone marrow transplantation
9. Gene therapy

37.  Blood transfusion is currently the most
effective and proven treatment for severe
anemia of SCD, it significantly reduces crisis.
 Blood transfusion reduces pain by increasing
the number of functioning RBC and by
increasing the oxygen caring capacity of blood

38.  Bone marrow transplant is the closest thing
possible to the cure of SCA.
 Helps in production of healthy RBC from
transplanted bone marrow
 The success rate is 90 – 95%

39.  Gene therapy is a relatively new idea of
inserting genes into the cells of an individual in
order to treat hereditary disease such as SCA,
in which a defective mutants alleles is replaced
with a functional one.
 Gene therapy would be the best cure for SCA
in future, as of now it is on it’s experimental
stage.

40.  Dialysis or kidney transplant for renal failure.
 Cholecystectomy for pigmented cholelitheasis.
 Hip replacement for avascular necrosis.
 Surgery for eye problem.
 Irrigation surgery for Priapism.
 Wound care for leg ulcer.

41. 1. Genetic counseling
2. Pre implantation genetic diagnosis
3. Perenatal testing -amniocentesis (16 – 18 wks)
and chorius villus sampling ( 9 -10 wks)

42. 1. Regular health check up & good hydration.
2. Vaccination for pneumonia, meningitis, influenza,
and hepatitis
3. Preventing infection – daily dose of penicillin
4. Preventing strokes – Transcranial doppler
ultrasound every 3 months.
5. Preventing eye damage – Fundus examination
every 3 months.
6. Avoid alcohol, smoking, cold climate, high
altitude exposure.
THERE ARE 4 MILLION SICKLE CELL DISEASED
PATIENTS WORLDWIDE