Risk Scale for the diagnosis of antiphospholipid syndrome

Abstract

According to the classification criteria of antiphospholipid syndrome (APS), lupus anticoagulant (LA), anticardiolipin (aCL) and anti-β2-glycoprotein I antibody (aβ2GPI)assays are independent risk factors for the occurrence of vascular thrombosis and pregnancy loss.1 It is generally accepted that patients carrying multiple positivity for antiphospholipid (aPL) Using these data, we set-up a risk model for APS diagnosis based on aPL positivity, their titre and methods used for LA research. Estimates for the probability of APS diagnosis were derived from logistic regression equations. The resulting chart (figure 1) shows that multiple aPL positivity, particularly the triple association of LA, aCL and aβ2GPI, increases the risk of APS. Among the aPL, LA is more strongly associated with the diagnosis of APS, particularly if detected with PTT-LA/STACLOT-LA or dRVVT. Interestingly, multiple positivity for different LA tests is not associated with a higher risk. Besides, the risk is estimated as ranging from low risk to high risk, according to subclassification of subjects based on aCL and aβ2GPI titres (as defined in figure 1). These data suggest a substantial improvement in risk prediction of APS diagnosis based on the assessment of the aPL profile, having the advantage of the quantification of such a risk by APS risk scale. From a speculative point of view, such an approach on the subclassification of patients based upon different combinations of positive tests may in future influence not only the prognostic judgment but also, more critically, the pharmacological treatment.

Antibodies to phosphatidylserine/prothrombin complex and the antiphospholipid syndrome

“…Recently, three score systems have been formulated to quantify the risk of thrombosis/obstetric events in APS, aiming to help physicians to stratify patients according to risk [20][21][22]. Two of those scores included antibodies to aPS/PT among the variables computed when assessing the risk for thrombosis or pregnancy morbidity [21,22].…”

New Tests to Detect Antiphospholipid Antibodies: Antiprothrombin (aPT) and Anti-Phosphatidylserine/Prothrombin (aPS/PT) Antibodies

“…Recently, three score systems have been formulated to quantify the risk of thrombosis/obstetric events in APS, aiming to help physicians to stratify patients according to risk [46][47][48]. Two of those scores include antibodies to prothrombin among the variables computed when assessing the risk for thrombosis or pregnancy morbidity [47,48].…”

Obstetric Antiphospholipid Syndrome: Has the Black Swan Swallowed a Red Herring?

“…It is informative that although PROMISSE is a longterm multicenter international study that includes only stringently evaluated, high-risk patients who fulfill (core-laboratory determined) APS laboratory criteria, there were only 144 aPL-positive pregnancies with 14 (9.7%) late losses between 2003 and 2011 20 . This low rate of late obstetric mortality in a high-risk population highlights the rarity and complexity of this clinical entity and the difficulties in acquiring an accurately identified sample sufficiently large to study 14,20,22 .…”

“…These patients often have an unpredictable pregnancy course regardless of therapeutic protocol. Their longterm prognosis has been reported to include a potentially higher risk of thrombotic events despite continuous anticoagulation 3,22,23 .…”

“…These patients have a high likelihood of live birth in a pregnancy subsequent to presentation regardless of therapeutic protocol, negligible risk of postpartum thrombosis, and a good longterm prognosis 22 . The less frequent presentation involves women with persistently high levels of aPL including LAC, a history of second or third trimester loss(es), and possibly a history of thrombotic events.…”