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Question 344
Physiology → Haematology
Classification
Question
SSBAQuestion Header
Several changes in blood composition can alter the erythrocyte sedimentation rate independently of a specific inflammatory diagnosis.
Question Stem
Which combination would be expected to increase the ESR?
Options
A
Microcytosis, polycythaemia and hypogammaglobulinaemia
B
Abnormal red-cell morphology, high cell number and low plasma proteins
C
Larger red cells, fewer red cells and increased plasma proteins
D
Polycythaemia, excessive anticoagulation and microcytosis
E
Hypofibrinogenaemia, high white-cell count and microcytosis
Explanation
ESR increases with larger cells, a lower amount of cells and more proteins. In contrast, polycythaemia, microcytosis, hypogammaglobulinaemia, hypofibrinogenaemia, excessive anticoagulation and a high white-cell count are factors that reduce ESR.
Option Validity
A) Microcytosis, polycythaemia and hypogammaglobulinaemia are all associated with a reduced rather than increased ESR.
B) A lower, not higher, amount of cells favours an increased ESR; abnormal red-cell conditions are associated with reduced ESR.
D) Polycythaemia, excessive anticoagulation and microcytosis are associated with reduction of ESR.
E) Hypofibrinogenaemia, a high white-cell count and microcytosis are factors that reduce ESR.
Further Reading
Saxena. Textbook for MRCOG-1. Physiology - Haematology - Erythrocyte Sedimentation Rate, p.68.