By ULY CLINIC
Antiphospholipid Antibody Syndrome (APLAS) in Pregnancy
Introduction
APLAS is an autoimmune disease characterized by the presence of maternal circulation of one or more auto antibodies against membrane phospholipids. It is an acquired condition.
Diagnostic Criteria
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Recurrent pregnancy loss (≥3 unexplained first trimester losses) or ≥1 unexplained second trimester pregnancy loss
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Unexplained venous or arterial thrombosis or myocardial infarction
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Autoimmune thrombocytopenia
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Unexplained Intra Uterine Growth Restriction (IUGR), abruption placenta and severe early preeclampsia (No agreement among experts, remains controversial in all three)
Diagnosis depends on correct clinical staging and serologic tests.
Investigations
At least 2 tests confirming the presence of circulating antiphospholipid antibodies is required to make the diagnosis of APLAS. Women with recurrent pregnancy loss (≥3 pregnancy losses) before 10 weeks gestation should be screened for APLAS.
Serology tests:
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Anticardiolipin Antibody (ACL)
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Lupus Anticoagulant (LAC). (tests include activated PTT test, Dilute Russel viper venom test, Kaolin clotting time)
Pharmacological Treatment
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Depends on the clinical features. The target international normalized ratio (INR) for vitamin K antagonist (VKA) therapy in APS should normally be 2.5 (target range 2.0–3.0) (1A).
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For women with APS with recurrent (≥3) pregnancy loss, antenatal administration of heparin combined with low dose aspirin is recommended throughout pregnancy (1B). In general, treatment should begin as soon as pregnancy is confirmed.
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For women with APS and a history of pre-eclampsia or fetal growth restriction (FGR), low dose aspirin is recommended.
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Women with aPL should be considered for post-partum thromboprophylaxis (1B).
Recurrent Pregnancy loss
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Prophylactic Unfractionated Heparin 5000– 10000 SC
OR
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Low Molecula Weight Heparin (Enoxaparin) 30–40mg SC daily
OR
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Dalteparin 2500–5000u SC daily starting in first trimester Patients with Thrombosis such as stroke or pulmonary embolism need therapeutic anticoagulation. D: Unfractionated Heparin (SC) 5,000 bolus and subsequent 15,000– 20,000 doses at 12 hourly interval
OR
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Low Molecular Weight Heparin (Enoxaparin) SC 1mg/kg 12 hourly
Note:
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The aPTT needs to be checked and is best done midway between the 12–hourly doses, once every 24 hours.
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A target of 1.5–2.5 times the control should be aimed
Referral
Refer immediate to a level where monitoring of the treatment through lab testing is available. Deep Vein Thrombosis in Pregnancy It is one of the major causes of maternal deaths
Diagnostic Criteria
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Pain
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Swelling or redness of the calf or thigh
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Homan’s sign (pain in the calf in response to dorsiflexion of the foot)
Investigations
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Venous ultrasound
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Venography
Pharmacological Treatment
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Unfractionated heparin (UFH) is the treatment of choice5 Loading dose 100U/kg (or minimum of 5000 U) followed by initial infusion 15-25 U/kg/hour (or minimum of 1000U/hour)
Note:
Check PTT every 4 hours and PTT should be maintained at 1.5–2.5 X control. Once steady state has been achieved measure PTT levels daily. Change heparin to SC route after 5–10 days
Referral
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Immediate referral to a hospital where monitoring of the treatment through lab testing is available is recommended
Updated on, 3.11.2020
References
1. STG