Monday, November 25, 2013

The Coagulation Cascade

A 30 year old postpartum woman presents with bleeding after minor surgery. She is G1P1 and recently delivered a healthy baby boy at 39 weeks. Her pregnancy was complicated by gestational diabetes mellitus, but there were no problems with the delivery. Three months after delivery she had her wisdom teeth pulled and had prolonged bleeding. She also noted increased epistaxis and mucosal bleeding. She has no other surgical history. She takes iron, has no allergies, has a nonsignificant social history, and has an otherwise negative review of systems. Her labs show an prolonged aPTT with a normal PT. You then take her plasma and mix it with pooled normal plasma; the aPTT remains prolonged.

Challenge: What does this mean? What's the most likely diagnosis?

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1 comment:

Craig said...

The Coagulation Cascade

This is an acquired inhibitor of coagulation; the most common is one that inhibits factor VIII (acquired hemophilia A). The test described is a mixing test or inhibitor screen. Correction of the aPTT suggests factor deficiency or von Willebrand disease; absence of correction (shown here) suggests a factor inhibitor.

Source: UpToDate.