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Question 313
Physiology → Haematology
Classification
Question
SSBAOptions
Explanation
Gum bleeding in scurvy results from a capillary abnormality rather than a clotting defect. Haemophilia A is an X-linked recessive factor VIII deficiency affecting the intrinsic coagulation pathway.
Option Validity
A) Factor VIII deficiency is the abnormality in haemophilia A, not scurvy. Scurvy-related gum bleeding is attributed to capillary abnormality.
B) This reverses the distinction. Scurvy is associated with capillary abnormality, whereas haemophilia A affects the intrinsic coagulation pathway.
C) Neither condition is attributed to platelet deficiency. Scurvy involves a capillary abnormality, whereas haemophilia A is a factor VIII coagulation defect.
D) Neither condition is an extrinsic pathway disorder. Haemophilia A affects the intrinsic pathway, whereas the scurvy example concerns capillary integrity.
Further Reading
Saxena. Textbook for MRCOG-1. Physiology - Haematology - Bleeding Time, Clotting Time and Haemophilia A, pp.71-72.