Lupus anticoagulant
1. Indicated for patients who are likely to have APS (To proceed)1:
 younger patients with unprovoked venous thromboembolism(VTE)
 VTE at unusual sites (e.g. splanchnic, cerebral, hepatic, portal)
 younger patients with ischemic stroke, transient ischemic attack or other evidence of
brain ischemia
 arterial thrombosis in other sites (e.g. adrenal/ splenic/ renal infraction, cryptogenic
acute limb ischaemia) in younger patients
 microvascular thrombosis - diagnosed by biopsy, often affect kidney and skin
 recurrent VTE unexplained by subtherapeutic anticoagulation, patient nonadherence,
or malignancy
 pregnancy morbidity:
i.
ii.
iii.

fetal loss after 10 weeks
recurrent (≥3) early (before 10 weeks) miscarriages
prematurity (<34 weeks’ gestation) associated with severe (pre)eclampsia,
HELLP syndrome or placental insufficiency (fetal growth restriction)
systemic lupus erythematosus: as preconception risk assessment for women of
reproductive age
2. LA testing could be considered in the following situations (To discuss with pathologist)1:
 immune thrombocytopenia, particularly with presence of arthralgias or arthritis, hair
loss, sun sensitivity, mouth ulcers, rash, thromboembolism
 livedo reticularis, particularly with presence of symptoms of other systemic
autoimmune diseases or mild thrombocytopenia
 younger patients with noncriteria clinical manifestations, i.e. those not included in the
Sydney criteria, e.g. cognitive dysfunction, valvular heart disease with presence of
evidence of other systemic autoimmune diseases
 patients of younger age following provoked VTE when the provoking environmental
factor is disproportionally mild
 patients with unexplained prolonged aPTT as an incidental finding
*Note: Younger patients (<50 years)
Rejection Criteria:
1. Patients who plan for continuing anticoagulant treatment
2. Patients who had provoked VTE (e.g., surgery, immobilisation, trauma, pregnancy)
3. Asymptomatic person who had first degree relative of DVT, PE or thrombophilia2
4. Patients on anticoagulant- should be discontinues as below:
i. Warfarin: 2 weeks after discontinuation
ii. UFH: 24 hours post dose
iii. LMWH: 24 hours post dose (min 12 hours)
iv. DOAC: 72 hours post dose (min 48 hours)
5. During acute episode of thrombosis (<12 weeks) unless suspect catastrophic APS2
6. During pregnancy or 6 weeks postpartum
Reference:
1. Devreese KMJ et al.. Guidance from the Scientific and Standardization Committee for lupus anticoagulant/antiphospholipid
antibodies of the International Society on Thrombosis and Haemostasis: Update of the guidelines for lupus anticoagulant
detection and interpretation. J Thromb Haemost. 2020 Nov.
2. Arachchillage, DJ et al. Thrombophilia testing: A British Society for Haematology guideline. Br J Haematol. 2022.
D-dimer
Indications:
1. Suspected DVT/PE in patients with low clinical probability1:
 DVT Wells score <2
 PE Wells score ≤ 4
(Please state the Wells score with clinical features scored)
2. Suspected PE in pregnancy: Follow YEARS algorithm2
3. Diagnosis of DIVC
4. Probable and confirmed severe Covid-19 disease (CAT4 and5)
Rejection Criteria:
1. Request with no clinical history or PE/ Well score to explain the indication
Reference:
1. NICE Guidelines. Venous thromboembolic diseases: diagnosis, management, and thrombophilia testing. March 2020.
2. van der Pol LM et. al. Pregnancy-Adapted YEARS Algorithm for Diagnosis of Suspected Pulmonary Embolism. NEJM. 2019.
3. NIH. The Covid-19 Tretament Guildlines Panel’s Statement on Anticoagulation in Hospitalised Patients with Covid-19. Updated
December1, 2022.
DVT Wells score
Clinical feature
Active cancer (treatment
ongoing, within 6 months, or
palliative)
Paralysis, paresis, or recent
plaster immobilisation of the
lower extremities
Recently bedridden for 3 days
or more, or major surgery
within 12 weeks requiring
general or regional anaesthesia
Localised tenderness along the
distribution of the deep venous
system
Entire leg swollen
Calf swelling at least 3cm
larger than asymptomatic side
Pitting oedema confined to the
symptomatic leg
Collateral superficial veins
(non-varicose)
Previously documented DVT
An alternate diagnosis is at
least as likely as DVT
Points
1
1
1
1
1
1
1
1
1
-2
PE Wells score
Clinical feature
Clinical signs and symptoms of
DVT (minimum of leg swelling
and pain with palpation of the deep
veins)
An alternate diagnosis is less likely
than PE
Heart rate more than 100 beats per
minute
Immobilisation for more than 3
days or surgery in the previous 4
weeks
Previous DVT/PE
Haemoptysis
Malignancy (on treatment, treated
in the last 6 months, or palliative)
Points
3
3
1.5
1.5
1.5
1
1