Autoimmune disease in pregnancy An autoimmune disease is one in which antibodies are developed against the host's own tissue .
I – Autoimmune thrombocytopenic purpura ( ITP ) : Autoimmune antibodies are produced against platelet surface antigens , leading to platelet destruction by reticulo- endothelial system . The incidence in pregnancy is 1 : 5000 .
Differential diagnosis : 1. Gestational thrombocytopenia Hypertensive disorder of pregnancy . 3. Others ( DIC , HELLP , acute fatty liver , thrombotic , thrombocytopenia ) .
Management : - Serial platelet counts - If platelet count < 50 x 109 / L approaching term : 1. corticosteroids 2. Intravenous immunoglobulin G 3. Final treatment : is splenectomy (risky ) 4. Platelet transfusion
Management : - In pregnancy , these antibodies may cross the placenta and destroy the fetal platelets . in < 5% of fetuses of women with ITP . So : 1) traumatic delivery should be avoided . 2) Platelet count of the neonate should be monitored .
II – Systemic lupus erythematosus ( SLE ) and antiphospholipid syndrome ( APS) - SLE : is a multi-system chronic autoimmune inflammatory disease . - SLE is a relapsing condition , and pregnancy increases the risk of flare.
Diagnosis : -By presenting > 4 of the 11 revised criteria of American Rheumatism Association - By finding of a positive assay for antinuclear antibodies , and the presence of antibodies to double- stranded DNA -anti Ro and anti La
Antiphospholipid syndrome ( APS ) : Is used to describe the association of : anticardiolipin antibodies and / or lupus anticoagulant . with typical clinical features of arterial or venous thrombosis . Fetal loss after 10 wks gestation or delivery before 34 wks due to IUGR or pre- eclampsia . > 3 miscarriages at less than 10 week's gestation . - APS may be primary or found in association with SLE
Maternal risks: - Lupus flare . - worsening nephropathy , proteinuria . - Thrombosis DVT , or even in unusual site ex. retinal vein . - Thrombocytopenia . - Placenta abruption .
Fetal risk: - Miscarriage . - Fetal death . - Growth restriction ( IUGR ). - Preterm labour . - Neonatal lupus due to transplacental passage of anti Ro/ anti . - Congenital heart block 1 – 2 % of babies of Ro-positive female .
Management of SLE and APS : *intensive monitoring for both maternal and fetal indications -baseline renal studies -The blood pressure -Serial U/S -steroids and azathioprine - NSAIDS should be avoided - warfarin LMW Heparin -aspirin + heparin
III – Rheumatoid arthritis ( RA ) : Chronic inflammatory , symmetrical arthritis causing joint pain , stiffness & deformity . 30 % antinuclear antibody + ve 20 – 30 % Anti Ro / anti La + ve 5 – 10 % A PL + ve
Its course 3/4 of them experience improvement of symptoms during pregnancy . R.A. has no adverse effect on pregnancy outcome, but the adverse effects may be due to treatment of the disease or passing abnormal antibodies through the placenta .
Treatment : Paracetamol corticosteroids NSADs avoided in pregnancy Azathioprine : Gold and pencillamine avoided in pregnancy . 6. Cytotoxic agent teratogenic & should be discontinued before pregnancy .