The key difference between Wintrobe and Westergren tube is that Wintrobe tube is calibrated in ascending and descending order while Westergren tube is calibrated from above to downward.
Erythrocyte sedimentation rate (ESR) is a common hematological test for the nonspecific detection of inflammation caused due to infections, certain autoimmune diseases, and some cancers. It is also defined as the rate at which red blood cells sediment in a period of one hour. In ESR, anticoagulated blood is allowed to stand undisturbed in a narrow vertical glass tube for a period of time; under the influence of gravity, the red blood cells settle out from the plasma. This method uses two glass tubes: Wintrobe and Westergren tubes. Wintrobe tube is also used to measure the packed cell volume.
CONTENTS
1. Overview and Key Difference
2. What is Wintrobe Tube
3. What is Westergren Tube
4. Similarities – Wintrobe and Westergren Tube
5. Wintrobe vs Westergren Tube in Tabular Form
6. Summary – Wintrobe vs Westergren Tube
What is Wintrobe Tube?
The Wintrobe tube is a narrow glass tube that is 110 mm in length and consists of a graduation of 0 to 100 mm in both ascending and descending order. The internal diameter of the tube is 3 mm, and the tube is closed at one end. A Wintrobe tube holds approximately 1 ml of blood. These tubes are made of borosilicate glass. They measure the rate at which red blood cells settle out of plasma.
The uses of the Wintrobe tube include determining the packed cell volume (PCV), determining Erythrocyte sedimentation rate (ESR), preparing a Buffy coat smear that is used to determine the LE cell phenomenon, and studying the abnormal cells in aleukemic leukemia cases. PCV is the ratio of the volume of packed red blood cells to that of the whole blood. A centrifugation step is performed during the estimation of PCV from the Wintrobe tube. Three layers are observed in the Wintrobe tube after centrifugation. They are plasma layer on top, buffy coat with white blood cells and platelets in the middle, and hematocrit or packed red blood cells in the bottom layer.
What is Westergren Tube?
Westergren tube is an upright, elongated tube used for estimating the sedimentation rate of red blood cells in fluid blood. This method involves measuring the distance (in mm) that red blood cells in anticoagulated whole blood fall to the bottom of a standardized tube over the course of one hour due to gravity.
Figure 01: Westergren Tube
Westergren tubes are used to measure the ESR with reference to the distance that the red blood cells settle to the bottom with a 2.5 cm internal diameter. Westergren tubes are used for the standard procedure of drawing blood in a liquid sodium citrate vacuum tube or a modified procedure, which includes using a saline-diluted EDTA vacuum tube. The method involves three stages. They are the state of aggregation, where the piling of red blood cells takes place; the stage of sedimentation, where the falling of red blood cells as sediments occurs at a constant rate; the stage of packing, where the packing of sedimented red blood cells in the column takes place.
What are the Similarities Between Wintrobe and Westergren Tube?
- Wintrobe and Westergren tubes are two glass tubes made of borosilicate glass.
- They are used to measure ESR.
- Blood is collected inside both tubes.
- Both tubes are calibrated in either cm or mm.
What is the Difference Between Wintrobe and Westergren Tube?
The Wintrobe tube is calibrated in ascending and descending order, while the Westergren tube is calibrated from above to downward. Thus, this is the key difference between Wintrobe and Westergren tube. A Wintrobe tube is a 110 mm long cylindrical glass tube, while a Westergren tube is a 300 mm long cylindrical tube. Moreover, the uniform bore diameter of the Wintrobe tube is 3 mm, while the diameter of the Westergren tube is 2.5 mm.
The below infographic presents the differences between wintrobe and westergren tube in tabular form for side-by-side comparison.
Summary – Wintrobe vs Westergren Tube
Wintrobe and Westergren tubes are two glass tubes. The Wintrobe tube is 110 mm long with a uniform bore diameter of 3 mm. It is calibrated from 0 to 100 mm in both ascending and descending order. Westergren tube, on the other hand, is 300 mm long with a bore diameter of 2.5 mm. It is calibrated as 0 -200 mm from above to downward. A Wintrobe tube is used to determine the packed cell volume (PCV), Erythrocyte sedimentation rate (ESR), and prepare Buffy coat smear. Westergren tube is used to determine the ESR with reference to the distance that the red blood cells settle to the bottom. So, this summarizes the difference between Wintrobe and Westergren tube.
Reference:
1. “Erythrocyte sedimentation rate (ESR).” The McGill Physiology Virtual Lab.
2. “Wintrobe Tube.” I Love Pathology.
Image Courtesy:
1. “StaRRsed pipet array” By MechESR – Own work (CC0) via Commons Wikimedia