ESR Flashcards
Erythrocyte Sedimentation Rate (ESR) measures
Rate of fall of RBCs settling in 1 hour (distance in mm).
ESR indication
Detect and monitor inflammatory conditions (e.g., rheumatoid arthritis).
ESR in sickle cell disease (SCD) - absence of crisis
Low ESR.
ESR in sickle cell disease (SCD) - during crisis
Moderately increased ESR (1 week into crisis).
ESR in osteomyelitis
Elevated, helpful in monitoring therapy.
ESR in stroke
> 28 mm/h indicates poorer prognosis.
ESR in prostate cancer
> 37 mm/h indicates higher incidence of progression and death.
ESR in coronary artery disease (CAD)
> 22 mm/h in white men indicates higher risk of CAD.
ESR in cancer patients
> 100 mm/h usually indicates metastases.
ESR in polymyalgia rheumatica and temporal arteritis
> 90 mm/h typical.
Moderate ESR elevations
Common in inflammatory diseases, chronic infections, collagen disease, neoplastic disease.
ESR diagnostic value
Limited diagnostic value in inflammatory disorders, useful for monitoring disease activity.
ESR limitations
Prone to technical errors, low specificity and sensitivity, not recommended as a screening test in asymptomatic individuals.
ESR technical limitations
Prone to errors, low specificity, low sensitivity, not recommended for asymptomatic individuals.
Westergren method
Results determined after 1 hr. & 2 hrs.
Westergren anticoagulant
3.8% Na citrate (4:1 ratio).
Modified Westergren method
Results determined after 1 hr., most commonly used.
Modified Westergren anticoagulant
EDTA.
Modified Westergren diluents
0.85% NaCl or 3.8% Na citrate.
Modified Westergren column size
200-mm column with 2.55 mm or more internal diameter.
ICSH
International Council for Standardization in Hematology.
CLSI
Clinical and Laboratory Standards Institute.
Wintrobe method
Results determined after 1 hr.
Wintrobe anticoagulant
Double oxalate or EDTA.
Wintrobe tube dimensions
Left side (red): 0 (top) and 10 cm (bottom) for ESR; Right side (white): 10 cm (top) and 0 (bottom) for Macro-hematocrit.
VES-MATIC 20 Instrument
Bench top analyzer for measuring ESR in 20 samples.
VES-MATIC 20 blood sample collection
Blood obtained in special cuvets and mixed by the instrument.
VES-MATIC 20 sedimentation time
Comparable to Westergren in 25 minutes for 1st hour, 45 minutes for 2nd hour.
VES-MATIC 20 tube slant
18-degree slant accelerates sedimentation.
VES-MATIC 20 sensors
Optoelectric sensors automatically read RBC sedimentation level.
Modified Westergren ESR reference range for adult males
0 to 10 mm/hour.
Modified Westergren ESR reference range for adult females
0 to 15 mm/hour.
Wintrobe ESR reference range for adult males
0 to 9 mm/hour.
Wintrobe ESR reference range for adult females
0 to 20 mm/hour.
Factors influencing ESR increase
↑ cholesterol, ↑ fibrinogen, ↑ gamma globulins, ↑ albumin, ↑ glucose, ↑ bile salts, ↑ phospholipids, Leukemia, Leukocytosis, Inflammatory conditions, Infections, Subacute bacterial endocarditis, Acute heavy metal poisoning, Collagen vascular diseases, Diabetes mellitus, End-stage renal failure, Hepatitis, Gout, Malignancy, Menstruation, Multiple Myeloma, Waldenstrom’s macroglobulinemia, Myocardial infarction, Rheumatic fever, Rheumatoid arthritis, Syphilis, Temporal arteritis, Nephrosis, Tuberculosis, Pregnancy, Cachexia, Congestive heart failure, Adults over 60 years of age.
Factors influencing ESR decrease
↓ albumin, ↓ fibrinogen, ↓ gamma globulins, Microcytosis, Acanthocytosis, Hemoglobin C, Sickle cells, Spherocytosis, Thalassemia, Refrigerated sample NOT returned to room temperature, Low room temperature, Narrow ESR column diameter.
RBC conditions increasing ESR
Anemia, Macrocytosis, Polycythemia, Anisocytosis (marked), Microcytosis, Acanthocytosis, Hemoglobin C, Sickle cells, Spherocytosis, Thalassemia.
Drugs that increase ESR
Dextran, Heparin, Penicillamine, Procainamide, Theophylline, Vitamin A, Adrenocorticotropic hormone (corticotropin), Cortisone, Ethambutol, Quinine, Salicylates.
Clinical conditions increasing ESR
Inflammatory conditions, Infections (acute and chronic), Subacute bacterial endocarditis, Acute heavy metal poisoning, Collagen vascular diseases, Diabetes mellitus, End-stage renal failure, Hepatitis, Gout, Malignancy, Menstruation, Multiple Myeloma, Waldenstrom’s macroglobulinemia, Myocardial infarction, Rheumatic fever, Rheumatoid arthritis, Syphilis, Temporal arteritis, Nephrosis, Tuberculosis, Pregnancy, Cachexia, Congestive heart failure, Adults over 60 years.
ESR error causes
Tilted ESR tube, Clotted blood sample, Delay in testing, Bubbles in ESR column, Vibration, High room temperature, Low room temperature.
ESR tilt error
A tilt of 30° from the vertical can cause error of up to 30%.
