To diagnose antiphospholipid syndrome (APS) it is necessary the presence of at least one clinical criterion (venous/arterial thrombosis or pregnancy complications) and persistent positivity of antiphospholipid antibodies (confirmed at least 12 weeks apart). The laboratory criteria to define the presence of antiphospholipid antibodies are: LA presence and/or increase of anticardiolipin and/or anti ß2 Glycoprotein I antibodies (IgG or IgM). Several variables can influence the result of the tests used for LA diagnosis, standardization of tests is poor and a wide inter-laboratory variability has been reported in terms of sensitivity and specificity. The probability of diagnostic errors (false negativity or false positivity) is therefore quite high. In order to improve the diagnostic accuracy of LA tests in 2009 the specific subcommittee for standardization of the methods of the International Society on Thrombosis and Haemostasis (ISTH) has updated the guidelines previously published. The Study Group on Coagulation of the Italian Society of Clinical Pathology and Laboratory Medicine (SIPMeL) summarizes in this article the ISTH guidelines. Subsequently, the Clinical & Laboratory Standard Institute (CLSI) has published its guideline which shows, in some respects, different or conflicting positions. Since the recommendations indicated by the CLSI are followed by many Laboratories, we tried to critically review these different positions. The Study Group of SIPMeL deems necessary to reiterate that for APS diagnosis the LA tests must be performed according to the ISTH guidelines.
|Translated title of the contribution||Italian Society of Clinical Pathology and Laboratory Medicine (SIPMeL)—guidelines for laboratory detection of Lupus Anticoagulant (LA)|
|Number of pages||9|
|Journal||Rivista Italiana della Medicina di Laboratorio|
|Publication status||Published - Sep 7 2018|
ASJC Scopus subject areas
- Medical Laboratory Technology
- Biochemistry, medical