Search This Blog

468x60.

728x90

13. Salpingitis, appendicitis (often normal), due to absorption of purulent necrotic material. FIG. 9.9: Wintrobe’s ESR tube with stand 222 Concise Book of Medical Laboratory Technology: Methods and Interpretations 14. Infected, necrotic or malignant tumors. 15. Liver disease (depends upon blood proteins). 16. Menstruation (slight acceleration). Slow ESR is Usually Seen in

 


Normal Values

Males—0 to 9 mm at the end of 1st hour. Females—0 to

20 mm at the end of 1st hour.

Microsedimentation (Landau) Method

Capillary blood can be taken.

Materials Required

1. 5.0 g/dL sodium citrate solution.

2. Landau pipette: This pipette resembles RBC pipette.

It is graduated from 0 to 50 mm.

FIG. 9.8: Westergren’s ESR pipette with stand

Contd...

Normal range, unit SI units

16 years 2800/µL or mm3 2800 × 106

/L

18 years 2700/µL or mm3 2700 × 106

/L

20 years 2500/µL or mm3 2500 × 106

/L

Platelets

Adults 150,000–400,000/ 150–400 × 109

/L

µL or mm3

Panic/Levels <30,000/µL or mm3 <30 × 109

/L

>l,000,000/µL or mm3 >1000 × 109

/L

Children

Newborn 100,000–300,000/

µL or mm3

100–300 × 109

/L

3 months 260,000/µL or mm3 260 × 109

/L

1–10 years 250,000/µL or mm3 250 × 109

/L

Panic/Levels <20,000/µL or mm3 <20 × 109

/L

> 1,000,000/µL or mm3 >1000 × 109

/L

Clinical Hematology 221

3. Landau pipette stand.

4. Suction device for drawing blood into the pipette.

5. Capillaries for blood collection.

Procedure

1. Attach Landau pipette to the suction device.

2. Draw 5.0 g/dL citrate up to first line on the stem.

3. Now draw blood by suction device up to second mark

on the stem (avoid air bubbles).

4. Wipe excess blood on the external side of the pipette.

5. Draw citrate solution and blood into the bulb of the

pipette. Mix the contents thoroughly.

6. Force back the mixture into the stem of the pipette.

7. Set the upper level of the mixture of the zero mm mark

at the top.

8. Detach the suction device.

9. Place the pipette in vertical position on the stand, set

time to one hour.

10. Note the reading (the distance red cells have fallen or

the extent of plasma column) after one hour.

Normal Values

Male: 0–5 mm after Ist hour. Female: 0–8 mm after Ist hour.

Zeta Sedimentation Rate (ZSR)

The zeta sedimentation rate (ZSR) is performed using a

special small-bore capillary tube that is filled with blood

and span for 3–4 minutes in a centrifuge called Zetafuge

(Beckman Coulter). This centrifuge alternately compacts

and disposes the RBCs under standardized centrifugal

force. The tube is then read on a special reader to obtain a

value called the Zetacrit, which represents the percentage

of sedimented erythrocytes. The Zetacrit value is divided

into the hematocrit value (also a percentage) and the

result in the ZSR expressed as percentage.

The ZSR’s advantages are that it is rapid, correct for

anemia, and requires only a small blood sample which

is desirable for pediatric patients. However, a special

centrifuge and reader are needed to perform the test.

Many other automated systems/devices are also

available.

Sources of Error for any ESR Method

1. Improper anticoagulant.

2. Tube not vertical, an inclination of 3° raises ESR by

almost 30%.

3. Dirty tube.

4. Bubbles caused by too vigorous mixing.

5. Hemolysis may modify ESR.

6. Prolonged storage of blood after withdrawing it, the

test should be performed within 3 hours.

7. Pipette/tube kept on a vibrating surface (vibration

prevents rouleaux formation).

Interpretation of ESR

The value of ESR is that it indicates the possible presence

of organic disease, or to follow the course of disease. Its

main use is as a prognostic tool. It is used as a diagnostic

criterion (minor) in rheumatic fever only.

Rapid ESR is Found in

1. In any chronic infection, e.g. tuberculosis (maximum

in miliary tuberculosis), has prognostic value.

2. Any extensive inflammation, cell destruction or

toxemia.

3. Pregnancy, after the second month.

4. Puerperium, returns to normal within 2 months.

5. Active myocardial infarction (rapid rise).

6. Acute myocardial infarction (rapid rise).

7. Active rheumatoid arthritis (not much elevated in

osteoarthritis).

8. Nephrosis (low blood albumin, anemia).

9. All types of shock.

10. Active syphilis (moderate acceleration).

11. Postoperative states (for variable periods).

12. Any active infectious disease, acute or chronic.

13. Salpingitis, appendicitis (often normal), due to

absorption of purulent necrotic material.

FIG. 9.9: Wintrobe’s ESR tube with stand

222 Concise Book of Medical Laboratory Technology: Methods and Interpretations 14. Infected, necrotic or malignant tumors.

15. Liver disease (depends upon blood proteins).

16. Menstruation (slight acceleration).

Slow ESR is Usually Seen in

1. Newborn infants.

2. Polycythemia.

3. Congestive heart failure.

4. Allergic states.

5. Sickle cell anemia (poikilocytosis).

Factors that Play a Role in ESR

1. Plasma Factors

¾ An accelerated ESR is favored by elevated levels of

fibrinogen, and to a lesser extent, of globulins (a and b

globulins are more effective than g globulin)

No comments:

Post a Comment

اكتب تعليق حول الموضوع

mcq general

 

Search This Blog