Hereditary Haemolytic Anaemias Flashcards Preview

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Flashcards in Hereditary Haemolytic Anaemias Deck (11):
1

Hypotonic lysis test

Main use for HS
Déterminés surface area: vol
Mix blood w graded concentrations of hypotonic saline and measure lysis colorimetrically
plot and the lysis from each of 12 tubes to create fragility curve

2

Factors affecting osmotic fragility test

Vol of hypotonic saline mix
Temperature
Ph- fragility increased by decreases. Ph

3

Increased osmotic fragility

He, elliptocytosis, hereditary stomatocytosis, Aiha( due to spherocytes)

4

Decreased osmotic fragility

Thalassaemia, iron def anaemia,
May have dec in hereditary enzyme disorders due to inc in reticulocyte count
Hereditary xerostomatosis

5

False positive - dec osmotic fragility not due to hs

Pregnancy
Haemolysis
Renal failure(?pH issue)

6

Best test for HS ne principle

Flow looking at eosin-5- malaise labelled red cells

7

Results ema

a ratio of mean value of the test to control sample.
a ratio of 0.8 or more is regarded as normal.

8

Acidified glycerol lysis time test

Same principle- looking at lysis based on surface area:volume
Good for screening family if known HS and minimal morphology
Use acid and glycerol

9

Autohaemolysis test-
1 with glucose
2 sans glucose

Normal blood there is minimal lysis- even less w glucose
Defects 1. If the result is entirely normal, an intrinsic red cell abnormality is unlikely. 2. If abnormal haemolysis is fully corrected by glucose, a metabolic abnormality is unlikely and a membrane abnormality is likely. 3. If abnormal haemolysis shows little or no correction by glucose, a metabolic abnormality is likely, provided that obvious features of spherocytosis are not present on the blood film.

10

Autohaemolysis test-
1 with glucose
2 sans glucose

Normal blood there is minimal lysis- even less w glucose
Defects 1. If the result is entirely normal, an intrinsic red cell abnormality is unlikely. 2. If abnormal haemolysis is fully corrected by glucose, a metabolic abnormality is unlikely and a membrane abnormality is likely. 3. If abnormal haemolysis shows little or no correction by glucose, a metabolic abnormality is likely, provided that obvious features of spherocytosis are not present on the blood film.

11

What genetic abn found in 20%babeie s iif mum w AFLP

LCAT deficiency