This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bleeding Disorders, Subject name: Pathology
A newborn baby presented with profuse bleeding from the umbilical stump after birth. Rest of the examination and PT, APTT are within normal limits. Most probable diagnosis is- 
Select and explain. 
A. Factor X deficiency, B. Glanzmann thrombasthenia, C. Von willebrand disease, D. Bernard soulier disease
B: Glanzmann thrombasthenia
Answer: B: Glanzmann thrombasthenia 
Explanation: Ans. (b) Glanzmann thrombasthenia(Ref: Robbins 9th/pg 660; 8th/pg 670)A newborn baby presented with profuse bleeding from the umbilical stump after birth.This is a case of severe inherited bleeding disorder. As PT & apTT are normal, Glanzmann thrombasthenia is the most probable cause, which can present with profuse bleeding soon after birth;It can be diagnosed by platelet aggregation studies, which will be defective.The other differential diagnosis in this scenario is Factor XIII deficiency (not given in the option)