Diagnosis of antiphospholipid syndrome

Antiphospholipid syndrome (APS) belongs to the group of rheumatic diseases and is characterized by the presence of autoantibodies to phospholipids. The reasons for the formation of autoantibodies are not precisely established. It is believed that most human viruses are tropic to the vascular endothelium. Persistent in them, the viruses cause morphological and functional changes in the cells; the destruction of the main membrane of the walls of the vessels caused by endothelium damage leads to the activation of the XII factor (Hageman) of the coagulation system and the development of hypercoagulation, as well as the production of autoantibodies. Autoantibodies block the endothelial membrane proteins (protein C, S, thrombomodulin) that inhibit thrombus formation, inhibit the activation of coagulation cascade components, inhibit the production of ATIII and prostacyclin, have a direct damaging effect on vascular endothelial cells. Interaction of antibodies with phospholipids of cell membranes leads to conformational and metabolic changes in membranes, disruption of cell function, stasis of blood in capillaries and venules, and thrombosis.

In some patients, antiphospholipid syndrome manifests primarily venous thrombosis, in others - stroke, in others - obstetric pathology or thrombocytopenia.

The frequency of antiphospholipid syndrome under different conditions

States	Frequency,%
Recurrent venous thrombosis	28-71
Habitual miscarriage	28-64
Transverse myelitis	50
Thrombocytopenia	27-33
Hemolytic anemia	38
Arterial thrombosis	25-31
The mesh guide	25
Pulmonary hypertension	20-40

Criteria for the diagnosis of antiphospholipid syndrome were formulated in 1998 at the VIII International Symposium on Antiphospholipid AT in Sapporo (Japan).

Clinical and laboratory criteria for diagnosis of antiphospholipid syndrome

Clinical criteria

• Vascular thrombosis

One or more clinical episodes of arterial, venous thrombosis, or thrombosis of small diameter vessels in any tissue or organ. Thrombosis should be confirmed by a picture of ultrasound Doppler scan or histological examination data, with the exception of superficial venous thrombosis. In histological examination, thrombosis should be represented by significant changes in the inflammatory vascular wall

 

• Diseases of pregnant women

One or more unexplained cases of death of a morphologically normal fetus at the 10th week or later of a normal pregnancy, and the normal fetal morphology should be documented by ultrasound data or by direct fetal examination,

Or

:

One or more cases of preterm birth of a morphologically normal fetus by the 34th week of pregnancy, or earlier due to severe preeclampsia or eclampsia, or severe placental insufficiency,

Or: three or more unexplained sequential abortions before the 10-week gestation period with pathological or anatomical abnormalities, or hormonal disorders, and chromosomal causes should be excluded from the father and mother

Laboratory criteria

1. Anticardiolipin antibodies IgG and / or IgM in the blood, moderate or high in 2 studies or more, taken at intervals of not less than 6 weeks, measured by standard ELISA for β ₂ -glycoprotein 1-dependent anti-cardiolipin antibodies
2. Positive lupus anticoagulant in plasma in 2 studies or more, received with an interval of not less than 6 weeks, and this anticoagulant should be determined according to the guidelines of the International Society of Thrombosis and Hemostasis in the following stages:
   • the establishment of the fact of elongation of the phospholipid-dependent phase of plasma clotting by screening tests such as APTT, co-aline time, Russell dilution test, prothrombin time with dilution
   • The inability to correct the extended time of screening tests by mixing with normal non-platelet plasma
   • shortening the time of screening tests or normalizing it after adding an excess of phospholipids to the test plasma and excluding other coagulopathies, for example, the presence of an inhibitor of factor VIII or heparin

Terms of diagnosis

The presence of at least one clinical and one laboratory test

[1], [2], [3], [4], [5], [6], [7]