Kalli, 35yrs old female presents with Bilateral deep vein thrombosis in legs. There is past history of recurrent foetal loss and one attack of pulmonary embolism. Screening tests of coagulation reveal a prolonged aPTT. Likely diagnosis is:
## **Core Concept**
The patient's presentation of bilateral deep vein thrombosis (DVT), recurrent fetal loss, and a history of pulmonary embolism, along with a prolonged activated partial thromboplastin time (aPTT), suggests an underlying coagulation disorder. This condition is likely related to an abnormality in the intrinsic coagulation pathway, which the aPTT test evaluates.
## **Why the Correct Answer is Right**
The correct answer, **Antiphospholipid Syndrome (APS)**, is a condition characterized by the presence of antiphospholipid antibodies, which can lead to both thrombosis and pregnancy complications. APS can cause a prolonged aPTT due to the presence of lupus anticoagulant, a type of antiphospholipid antibody that can interfere with phospholipid-dependent coagulation tests like the aPTT. The patient's history of recurrent fetal loss and episodes of thrombosis (DVT and pulmonary embolism) are also consistent with APS.
## **Why Each Wrong Option is Incorrect**
- **Option A:** While Factor V Leiden deficiency can cause thrombophilia, it typically presents with a normal aPTT but a prolonged prothrombin time (PT) or activated protein C resistance test. It doesn't fully explain the prolonged aPTT.
- **Option B:** Protein C deficiency can cause thrombophilia but usually does not cause a prolonged aPTT. It affects both PT and aPTT in a different manner and is associated with warfarin-induced skin necrosis and not specifically with recurrent fetal loss as a hallmark.
- **Option C:** This seems to be a distractor as there's no provided text; however, any condition not directly linked to a prolonged aPTT and the clinical presentation described would be incorrect.
## **Clinical Pearl / High-Yield Fact**
A key clinical pearl is that **Antiphospholipid Syndrome** can present with a prolonged aPTT due to the lupus anticoagulant. However, despite the prolonged aPTT suggesting a bleeding tendency, APS paradoxically causes thrombosis. This condition is a classic cause of thrombophilia and should be considered in patients with recurrent thrombotic events and pregnancy complications.
## **Correct Answer:** . **Antiphospholipid Syndrome**