Guidelines for the Laboratory Investigation of Inherited Thrombophilias. Recommendations for the First Level Clinical Laboratories

Abstract

Recent advances in the laboratory diagnostic approach to inherited thrombophilia call for an update on laboratory strategies and organization. The present paper therefore deals in particular with: the panel test choice, timing and test appropriateness, and analytical methods in several clinical conditions. Specific recommendations are supported by the state-of-the-art in this branch.

Inappropriate use of protein C, protein S, and antithrombin testing for hereditary thrombophilia screening: an experience from a large university hospital

“… Acute thrombosis: PC, PS, and AT may be decreased in this condition and commonly not recommended for testing in many guidelines (Adcock, Fink & Marlar, 1997; Anonymous, 2001; Buchanan, Rodgers & Ware Branch, 2003; Carraro, 2003; Tripodi, 2005). However, the definition of acute thrombosis in these guidelines was not precisely defined.…”

“…Testing during acute thrombosis in this study meant blood samples taken during the admission owing to symptomatic thromboembolism prior to anticoagulant administration. Pregnancy or within 2 months of the postpartum period: decreased AT and PS (Adcock, Fink & Marlar, 1997; Tripodi, 2005). Receiving warfarin or within 2 weeks after its cessation: decreased PC and PS (Adcock, Fink & Marlar, 1997; Buchanan, Rodgers & Ware Branch, 2003; Carraro, 2003; Tripodi, 2005). Receiving heparin or within 5 days after its cessation: decreased AT.…”

“…Receiving heparin or within 5 days after its cessation: decreased AT. (Buchanan, Rodgers & Ware Branch, 2003) Receiving oral contraceptives or within 2 months after cessation: decreased PS (Carraro, 2003). …”

“…Patients with arterial thrombosis such as myocardial infarction, peripheral arterial occlusion (Adcock, Fink & Marlar, 1997; Buchanan, Rodgers & Ware Branch, 2003; Tripodi, 2005). Patients having coagulation disorders (prolonged PT or prolonged PT and APTT) such as liver disease, disseminated intravascular coagulation, or vitamin K deficiency because these conditions can affect the results of these proteins (Adcock, Fink & Marlar, 1997; Carraro, 2003). …”

Thrombophilia – How Far and How Much to Investigate?

“…Thus, if family screening for thrombophilia is to be performed, extensive laboratory testing should be considered for both symptomatic and asymptomatic family members. Needless to say, other still unknown thrombophilia defects can be present in families with severe VTE manifestations [33].…”