Hereditary Spherocytosis -HS for Lab.students

1. 1-Hereditary spherocytosis HS
Hemolytic anemia Red Cell Membrane Disorders
Developed by-Dr.Abdulrazzaq Othman Alagbare
M.D M.S.c C.P - Lecturer of Hematology and Immunohematology
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2. Introduction
• Autosomal dominant inherited disorder of Red blood cell membrane
disorder
• It is type of extravascular hemolysis
• With spherical shape on the PBS over 50% of RBC.
• Caused by defect is in proteins of the membrane skeleton, (spectrin, ankyrin
etc) THIS alterations lead to the loss of cell surface area, increased rigidity.
ANEMIA -Dr.Alagbare
Red Cell Membrane Disorders
1-Hereditary spherocytosis HS

3. Mechanism
Increased permeability of the membrane to sodium.
Increase of the permeability of the RBC membrane allow to
sodium with water to inter inside the cells, become more
spherocytic, with the result RBC destruction in spleen
Presence of spherocytes on the peripheral blood smear
ANEMIA -Dr.Alagbare
Hereditary spherocytosis

4. ANEMIA -Dr.Alagbare
 Hb
 PCV
 MCV
 Moderate anemia
 Low
 Low
MCHC >38 g/dl
HS anemia have MCHC values above normal range
Reticulocytes count 10-15%
HS-Diagnosis –CBC result

5. ANEMIA -Dr.Alagbare
P.B. Smear:
- Show spherocytes RBC (small diameter,
lack central pale.) over 80%
- Reticulocytosis

6. ANEMIA -Dr.Alagbare
The diagnostic test for HS is
 “Osmotic Fragility Test”
Flow cytometry - Eosin-5-Maleimide
dye binding (E5MA dye binding
test )
Chemistery tests
 DAT: Negative
 Serum haptoglobin: Decrease
 LDH: Increase
 Indirect Bilirubin: increase
 Osmotic Fragility Test”

7. 2- Eosin-5-Maleimide dye binding
E5MA dye binding test
 Method : Flow cytometric
 Specimen: blood with EDTA
anticoagulated
Who its work this dye?
 Binds to normal red cell membrane
proteins, mainly to band 3 protein.
ANEMIA -Dr.Alagbare
Normal
HS
case
 Result in HS patients  will have
reduced dye binding with EMA

8. Osmotic Fragility Flow Cytometry
Must be performed within 6 hrs Reproducible up to 72hrs
Result within 24hours Result within 1hour
3ml blood 100ul blood
Unreliable on patients recently transfused Results abnormal after blood transfusion
Sensitivity 80% (mild cases missed) Sensitivity 93%
Abnormal in other causes of spherocytosis
(AIHA)
Specificity 99%
Comparison between OFT and Dye binding method
6/17/2020
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Metabolic Disorders

9. 9
STEPS OF Laboratory diagnosis of HS
 Spherocytosis on blood smear
 Reticulocytosis
 Red cell indices: ↑MCHC, ↓MCV
 Negative direct antiglobulin test
 Screening test: OF test, EMA binding test

10. 2-Hereditary Elliptocytosis (HE)
3-Hereditary stomatocytosis
4-Hereditary pyropoikilocytosis (HP)
Hemolytic anemia Red Cell Membrane Disorders
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11. Patients with HE have a spectrin abnormality.
too, but the mutation is different than that in HS.
Hereditary morphological disorder, the
severity of disease varies, from severe
hemolytic disease to asymptomatic carrier
Diagnosis: only from the P.Blood
smear with 25% to 100% elliptical RBCs;
6/17/2020
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Metabolic Disorders
2-Hereditary Elliptocytosis (HE)

12. 3-Hereditary stomatocytosis
 Rare
 Autosomal dominant inheritance
 Specific membrane abnormality
 Clinical presentation – asymptomatic
to moderately severe disease
Diagnosis P.B.S
 More than 25% stomatocytes are
required for a diagnosis.
6/17/2020
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Metabolic Disorders

13. HP is a membrane defect
characterized by
 a spectrin abnormality and
thermal instability.
 The MCV is decreased and the
red cells appear to be budding
and fragmented
 The MCV may be as low as 25-
55 fL.
4-Hereditary pyropoikilocytosis (HP)

14. Anemia RBC changes on the PBS
 Hereditary spherocytosis –H.S Spherocytes over 80%
 Hereditary Elliptocytosis – H.E >25% Ovalocytes
 Hereditary pyropoikilocytosis
(HP)
appear to be budding and
fragmented.
 G6PD deficiency • Blister cell, Bite cells
• Basophilic stippling
• Heinz bodies
ANEMIA -Dr.Alagbare

15. ‫رب‬ ‫هلل‬ ‫الحمد‬
‫العالمين‬
‫ابتغي‬ ‫العمل‬ ‫هذا‬
‫الكريم‬ ‫هللا‬ ‫وجه‬ ‫به‬
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