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Purpose of ESR

To detect the presence of inflammation caused by
• Infections
• lymphoproliferative disorders
• autoimmune diseases


What does ESR Aid in diagnosing:

• Multiple Myeloma
• Rheumatoid arthritis
• Lupus erythematosus


Theory of ESR

• Rate at which RBCs fall (sediment) within a set time (one hour)
• The red blood cells become sediment at the bottom of the tube leaving blood plasma at the top of the column
• The ESR is nonspecific, meaning that it does not tell the doctor exactly where the inflammation is occurring in the body
• Units mm/hr ( manual)
• Automated mmm/time


Increased Results (red cell falls more rapidly) of ESR

• Rouleaux – stacked like coins instead of separated in monolayer (caused by increased fibrinogen – protein)
• Fibrinogen (protein involve in inflammation)
• Immunoglobulin (protein involve in inflammation)
• Pregnancy
• Anemia
• Auto immune disorder (RA and lupus)
• Lymphoma
• Myeloma


Decreased Results (red cell falls slowly) **

• High RBC - polycythemia
• Some RBC shapes: example sickle cells
• Leukemia
• Congestive heart failure
• Hyperviscosity


Manual Westergren Method

200 mm open ended tube
• Black Top Tube (2.4 mL draw into 0.6 mL citrate)
• Many medical laboratories use lavender top EDTA sample.
• Difference in results are not usually clinically or statistically significant.


Procedure Manual Westergren

• Use pipette filler to fill ESR tube until cotton plug is wetted to prevent leaking.
• Set up vertically in rack; record mm that RBCs fell in 1 hour


Normal Range; Westergren

• males 0 - 15 mm /hr
• females 0 – 20 mm /hr


Wintrobe method

: 100 mm closed ended tube
• EDTA blood –lavender top tube
• Record mm blood falls in one hour
• Method not as sensitive as Westergren ESR

Reference range
• Males and Females: 0-9 mm/hr


Automated Methods

- specimen is collected in special vacuum tubes made specifically for the automated ESR instruments(Black Top vacutainer)

• random access of samples
• 15 minute test
• correlates with manual Westergren



30 min test using ESR vacuum tubes correlates with Westergren
• 100 channels
• Throughput 400 tests per hour
• Temperature compensation
• Tube employed: Special 8 x 120 mm tubes
• Reading time 15 minutes Random access
• On board printer, barcode and scanner


VES- MATIC Automated ESR

• Correlated to Westergren Reference method
• 30 positions
• Automated mixing
• Barcode reader for positive sample identification.
• Rapid results: - 20 minutes, standard mode - 10 minutes, fast mode
• Use Bi-level QC material
• Connectivity to LIS
• Small sample volume- 1ml
• Closed sample tube system reduces health and safety risks


Falsely Increased ESR

Tube not vertical
Incorrect timing (too long)
Room temp >25º C
Incorrect mixing of sample
Vibration of tube during test


Falsely Decreased ESR

Air bubbles in tube
Incorrect timing (too short)
Blood specimen below RT
Fibrin clots
Hemolyzed samples


Precaution and Technical Factors (Quality Assurance)

• use Bull’s eye level on ESR rack to ensure tubes are vertical(manual method)
• Test must be set up within 2hrs of blood collection
• Use approved commercial controls


Malaria Parasites

Malaria is a serious and sometimes fatal disease caused by a plasmodium parasite that commonly infects a certain type of mosquito which feeds on humans.


Four kinds of malaria parasites infect humans:

• Plasmodium falciparum- severe and may lead to death if untreated
• P. vivax
• P. ovale
• P. malariae.

p. knowlesi, a type of malaria that naturally infects macaques (monkey) in Southeast Asia, also infects humans, causing malaria that is transmitted from animal to human (“zoonotic” malaria).

Symptoms usually appear between 10 and 15 days after the bite but can appear after one year.



• Malaria is caused by the intracellular parasite, Plasmodium which is transmitted via the bites of infected female Anopheles mosquitoes.

• In the human body, the parasites multiply in the liver, and then infect RBCs.

• Can be transmitted through
o Blood transfusion
o Organ transplant
o Shared needles or syringes contaminated with blood.

• Malaria may also be transmitted from a mother to her unborn infant before or during delivery (“congenital” malaria)


Symptoms of malarial infection

• High fever
• headache
• vomiting
• shaking chills
• muscle aches
• tiredness


Thick smear malaria smear

• Prepare two smear, using venous or capillary blood or EDTA blood
• Spread droplet of blood using spreader slide in a circular motion (size of a 25cent coin)
• Let dry thoroughly
• Stain without fixing using diluted Geimsa
• RBCs are lysed and blood film can be examined for parasites
• Plasmodium stains blue with red chromatin dot,

If the Thick smear is positive then the thin smear is used to identify species

All positive blood specimens go to Public Health lab for confirmation of specie and documentation.


Thin smear malaria smear

• Prepare two smear in standard fashion using venous or capillary blood
• Stain with Wright’s Geimsa or Geimsa
• Look for Plasmodium inside or outside RBCs
• Used to identify Species


Types of Identification Tests for Malaria

1. Thick and thin blood film
2. Antigen detection
3. PCR (Polymerase Chain reaction) Molecular- used to confirm specie
4. Serology-detects antibodies against malaria parasites