07. Bad Obstetric History - Suchitra Pandit

March 17, 2018 | Author: ameen | Category: Thrombosis, Medical Specialties, Diseases And Disorders, Wellness, Health Sciences


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Antiphospholipid SyndromeProf. Dr. Suchitra N. Pandit MD, DNBE, DFP, FRCOG, FICOG, B.Pharm Consultant Obstetrician & Gynaecologist Kokilaben Dhirubhai Hospital, Mumbai ,India Clinical secretary –MOGS, Vice President - FOGSI (2008-09) Chairperson -Young Talent promotion committee FOGSI (2003-07) Antiphospholipid ( APLA ) syndrome  Antiphospholipid syndrome (Hughes syndrome) is a disorder of immune system ,characterised by excessive clotting of blood ,thrombocytopenia & /or adverse pregnancy outcomes  Body recognizes negatively charged phospholipids on cell membrane as foreign & produces antibodies against them leading to an acquired autoimmune thrombophilia  Patients have laboratory evidence for antibodies ( IgG, IgM or IgA ) against phospholipids or phospholipidbinding protein cofactors in their blood How many types of APLA syndromes are there  A.) two  C.) Three  D.) Four .) One  B. Antiphospholipid antibody syndrome (APLA)  Primary antiphospholipid syndrome (PAPS) .when APS occurs in the absence of any other related disease (LA.  Secondary antiphospholipid syndrome . APS leads to rapid organ failure due to generalised thrombosis & a high risk of death  Other rare antibodies to phosphotidyl ethanolamine & phosphotidylserine are also associated with it .when APS coexists with other diseases such as SLE I  In catastrophic APLA (rare ). ACL antibodies in patient’s serum). Thrombophilic defects either acquired or inherited . tendency to thrombosis Acquired APLA Lupus anticoagulant antibodies Anticardiolipin antibodies  Myeloprolipherative diseases  Malignancy  Paroxysmal nocturnal Haemoglobinuria  Nephrotic syndrome .Thrombophilia . Inherited  Hyperhomocysteinemia (C677T) mutation  Factor V Leiden mutation (A506G) mutation  Mutation in prothrombin ( G 20210 A)  Prothrombin II (PTII) mutation  Protein S deficiency  Protein C deficiency . ) Arterial or venous thrombosis C.All these conditions should be investigated for APLA except : A.) Unexplained fetal growth restriction D.) Gestational Diabetes .) Early onset severe preeclampsia B. Primary antiphospholipid antibody syndrome Presentation may be totally asymptomatic or in a classical manner : Various clinical presentations :  Recurrent pregnancy loss  Unexplained second or third trimester loss  Early onset severe preeclampsia  Arterial or venous thrombosis  Unexplained fetal growth restriction  Prolonged coagulation studies  Autoimmune diseases  Cardiac valvular diseases  Neurological disorders  Thrombocytopenia . .  Lack of agreement between laboratories concerning standardization of the assays  Debates among researchers & clinicians concerning which antibodies to measure.Diagnosis of APLA Challenging !!!  Due to fluctuating titers of the antibodies. ) Lupus Anticoagulant (LAC) C.) Anticardiolipin Antibodies (ACL) D.) Anti Ro B.Which is not an APLA antibody ? A.) Anti insulin antibodies . Which are the Antibodies  Lupus Anticoagulant (LAC)  Anticardiolipin Antibodies (ACL)  Anti Beta 2 glycoprotein antibodies  Other antibodies . . Abruption .34% .9.1% Early pre eclampsia .33% Systemic lupus erythematosus .16%. causing aggregation & thrombosis & also interferes with endothelial function.Lupus anticoagulant ( LAC)  LAC is characterized by a prolonged partial thromboplastin time & paradoxically the so-called ‘anticoagulant’ is a powerful thrombotic agent in vivo  Higher thrombotic potential than ACL when present alone  LAC interferes with platelet function. causing procoagulant activation & thrombosis  Prevalence of LAC in low risk population is < 1% Bad obstetric history . (TDT/DTT) or prothombin time  Due to heterogeneous nature of LA .minimum of 2 tests required. 6 weeks apart & should be positive each time showing persistent positivity to confirm diagnosis of APLA Caution : patients with transient positive tests (due to infection etc) can be diagnosed as positive. Kaolin clotting test (KCT). . Patient typically has a prolonged APTT that does not correct in 80:20 mixture with normal human plasma  Prolonged Dilute Russel viper venom time (DRVVT). ) D.) Activated partial thromboplastin B.Lupus anticoagulant (LAC) Prolongation of which of these tests is most sensitive for LAC ? A.) C.) Dilute Russel Viper venom Kaolin clotting time Partial Thrombin time . Anticardiolipin Antibodies  Were thought to react against cardiolipin but it is now thought to interact with B2GP1  85% of APS pts have both LA & aCL  These can be detected using an (ELISA)  Screens for the presence of β2 glycoprotein 1 dependent anticardiolipin antibodies (ACA)  A low platelet count & positivity for antibodies against β2-glycoprotein 1 or phosphatidylserine may also be observed in a positive diagnosis . regulation of protein S. .  Binds to B2GP1 disrupting f(x)  B2GP1 has anticoagulant activity through the inhibition of the conversion of prothrombinthrombin.Anti Beta 2 GP1  Discovered after LA & ACL  Found without other two in 11% of APS pts & commonly with others. & /or activation of platelets. arterial. or small vessels disease ‘ Coexisting inherited or acquired thrombotic risk factors are not reasons for excluding patients from a diagnosis of APS trials.’ . one or more confirmed episodes of venous.Sapporo criteria International Consensus Conference held in Sapporo (’98) Clinical criteria of ( APAS ) Thrombosis. 2006.Sapporo Criteria (updated)    Pregnancy criteria : One or more unexplained fetal deaths > 10 wks of pregnancy One or more preeclampsia / eclampsia or placental insufficiencies occurring before 34 weeks . J. clot-based assay (ISTH guidelines) ACL (IgG or IgM) antibody Anti-b2 glycoprotein I . Haemost. 4: 295-306. et al...IgG or IgM antibody Miyakis.    . Three or more unexplained consecutive spontaneous abortions < 10 weeks Laboratory criteria LAC defined by a functional. Thromb. The International Consensus Statement Definite CAPS diagnosis requires:  Vascular thrombosis in three or more organs or tissues & development of manifestations simultaneously or in < a week & small vessel thrombosis in at least one organ or tissue  Lab. confirmation of presence of aPL  Some serological tests for syphilis may be positive in aPL- positive patients if it is positive) although more specific tests for syphilis that use recombinant antigens are negative  Transient elevations common. Elevations common in autoimmune disease & infections ex. HIV, Hep C, syphilis Principal pathogenic mechanisms mediated by APL Interference with a.) Soluble coagulation factors Protein C/S pathway inhibition; fibrinolysis inhibition Induction of a pro-adhesive, proinflammatory & pro-coagulant endothelial phenotype ; induction of a procoagulant phenotype in monocytes b.) Coagulation cells: Interference with : a.) Trophoblast cells: Reduction of proliferation & differentiation; Gonadotrophin secretion impairment Pregnancy losses classified as :  Occult (preclinical or chemical) pregnancy loss prior to missed menses. (40% of implantation embryos)  Early pregnancy loss before 12 wk. (13%)  Late pregnancy loss after 12 wk. (1%) Causes of pregnancy loss Chromosomal 55% of occult & early losses 5% of recurrent losses. anatomical Immunological 45% of early losses 95% of late losses Environmental hormonal . Aneuploidy Aneuploid fetus risk in women > 35yr. age Inherent risk of fetal loss after amniocentesis 1/80 1/200 Standard of care is to offer genetic amniocentesis for all pregnant women older than 35 years . What is Recurrent pregnancy loss ? What actually causes it ? . under 20 week gestation from the last menstrual period by the same partner.Definition A recurrent pregnancy loss (RPL) is 3 or more consecutive.  Primary recurrent pregnancy loss" refers to couples that have never had a live birth  “Secondary RPL" refers to those who have had repetitive losses following a successful pregnancy . spontaneous pregnancy losses. a phospholipid-binding protein with potent anticoagulant activity. CJ. H. -N Engl J Med . Lockwood.Pregnancy loss in the APLA syndrome . J Scher. Peter Harpel. 1997 . are markedly reduced on placental villi from women with APLA  APL antibodies reduce the levels of annexin V & accelerate the coagulation of plasma on cultured trophoblasts & endothelial cells. Andree. Jacob Rand. 337:1630-1631. Xiao-Xuan Wu.A possible thrombogenic mechanism  Levels of annexin V. Seth Guller.  Reduced annexin V levels on vascular cells may be an important mechanism of thrombosis & pregnancy loss in APLA syndrome. recurrent pregnancy loss & stillbirth are common  Systemic lupus erythematosus (SLE) is prototype . prematurity. scleroderma.  Antibody is directed against cellular ribonucleoprotein complexes which is present in serum of > 10% pts of CTDs. Behcet’s disease & Sjogren’s syndrome  Recent studies show anti-Ro/SSA antibody as a possible factor for unexplained pregnancy loss in SLE. others are rheumatoid arthritis.Pregnancy loss in autoimmune connective tissue disorders (CTDs)  Adverse outcomes like IUGR.  It is associated with neonatal lupus & congenital heart block showing passively acquired autoimmunity . maternal & fetal surveillance . dealing with complications  Timely referral to a tertiary centre .How do you proceed ?       Interview the couple together History of the case is very important Clinical examination Investigations as per the history Reassurance & counselling Treatment plan : Drugs. ELISA . KCT . anti La (SSP) . TTIT  Most accurate . anti-Ro/SSA antibody.Special Investigations  LAC tested by prolonged coagulation time (inhibition of phospholipids)  APTT .Dilute russel viper venom test (DRVVT)  ACL . anti –nDNA.IgG (GPL) IgM (MPL)  IgG/ IgM isotypes of anticardiolipin & antiphosphotidyl serine antibodies  In c/o low titres-repeat after 6-8wks (can revert to normal)  Transient low titres can be found in viral fever  If autoimmune disorders are suspected ANA. antiSm. So how does one manage the drug treatment in pregnancy ? General guidelines for anticoagulation in Pregnancy with APS leading to recurrent pregnancy loss Very controversial issue ! . Commonly used Drugs • Steroids : Reduces ACA. preeclampsia • Low dose Aspirin (LDA) : Selective inhibition of Thromboxane A2 No effect on PGI2 • Azathioprine • Warfarin . normalises prolongation of invitro coagulation • Complications : ? perinatal outcome preterm labour. 486 .Which is the commonly used drug for APLA ? A.) Folic acid C.) Low dose Aspirin D.) RU.) Progesterone B. less monitoring  Lesser osteopenia. does not cross placenta  Cost factor !! .D. Low molecular weight Heparin (LMWH)  Once daily dose.Unfractionated Heparin (UFH)  Potentiates complex formation with AT III + factor VII A  XII A & thrombin  Complications : Reduces platelet bleeding & B.M. 1994 .S.Trials  Heparin vs Aspirin + prednisolone Live birth 75% Pre-eclampsia. + LDA Vs Heparin + LDA (n=20)  No placebo  Large multicentric trials needed Cowchock et al . preterm delivery more in latter group  L. .Randomised controlled trial of LDA versus LDA plus heparin in pregnant women with APS  90 women with APS were randomized into two groups with 1st group receiving 75mg of LDA & 2nd group LDA & Heparin 5000u subcut. (1997 ) .Cohen et al.BMJ. every 12 hourly  Outcomes measured were number of live births & miscarriages  LDA group had 19 live births & 26 miscarriages  LDA + heparin group had 32 live births & 13 miscarriages  Significant (p=0. Rai. H..01) improvement in outcomes with heparin R. Antiphospolipid antibodies Presence of Antiphosholipid antibodies may cause recurrent pregnancy loss  Are antibodies directly responsible ?  Should all women with APA be treated ?  How do you treat a women with positive APLA ? . Controversies surrounding treatment for pregnancy loss  Evidence-based medicine (EBM) has not succeeded in giving patients & physicians the data they need to choose (or not choose) a therapy in the field of pregnancy loss . 0.4.0 .  Patients with APLA have minor elevations of PT & are difficult to manage with warfarin.000 u 12 hourly .  During pregnancy.Maintain INR between 3. Women with APLA are advised to take LDA & to start LMWH Rx after pregnancy is diagnosed (80% success)  In case of H/o thrombotic symptoms.  If UFH is used dose is 10. Warfarin is used as anticoagulant . LMWH & LDA are preferred to Warfarin (teratogenic effects )  If previous H/o thrombosis use LMWH in therapeutic doses throughout pregnancy :dose 1mg/kg subcut. Measure LMW heparin levels in these patients for long term Rx (0.35 .0 anti-Xa units)  Perform prothrombin & proconvertin times ("P&P") to follow anticoagulation. If UFH used to anticoagulate patients with APLA monitor heparin levels ( 0.7 . Since APLA reacts with phospholipids both aPTT & PT can be affected.1.  With LMWH .  If miscarriage occurs with heparin & aspirin & there is a pregnancy again IVIG can be tried (RCT did not show benefit)  In refractory cases plasmapheresis may be used .70 anti-Xa units 6 hours post injectiont ). monitoring is easier : predictable dosing & anticoagulant effect .0. Being less dependent on phospholipids & one can monitor therapy. et al. 1C . no prior VTE or pregnancy loss Recommendation Surveillance. & /or aspirin Grade 2C Antiphospholipid antibody. or mini-dose heparin. 2004. plus low-dose aspirin.644S .Bates.. or prophylactic LMWH. prior thrombotic event Adjusted dose UFH or LMWH.ACCP Guidelines : Pregnancy & APL Manifestation Antiphospholipid antibody. Chest. 126: 627S . Can pregnancy outcome be improved ? . Management of pregnant women  Surveillance depends on past obstetric history  LDA preconception & LDA + LMWH has 80% success rate for treatment of APLA ( Feinberg et al.  Refer preferably to a tertiary centre with a neonatal backup  Team effort including an obstetrician . renal function test (to asses target organ damage ) . & neonatologist  Vigilant monitoring  B.’ 97 ). platelets.P. hematologist. physician. complement levels . G : viability & dating .S.G at 19 weeks & serial scans with doppler for early diagnosis of IUGR & waveform abnormalites  Inj Betamethasone 2 doses for enhancing lung maturity  Timely delivery in a centre with a good neonatal backup .S.Care of the fetus  Surveillance depends on past obstetric history  1st trim U. nuchal & nasal bone  U. IVIG .Future Possibilities  PAPRE warfarin intensity  PRECLUDE primary prevention  More frequent use of LMWH. or neurological syndromes & so no role in the Rx of thrombotic APLA . fetal loss. many will never develop thrombosis  The current recommendation would be to do very careful search for thrombosis. but immunosuppression does not prevent recurrent thrombosis. especially those with SLE.What to do with the patient with APLA but no thrombotic manifestations ?  Although some of these patients are at risk. Brain MRI in patients with SLE & in patients with any neurological symptom  If this work-up is negative follow the patient very closely Does immunosuppression work ? APLA seems like an autoimmune disease.  Low intensity anticoagulation with warfarin appears to be mostly effective in APLA (except patients with venous thrombosis)  Many patients will fail low intensity warfarin & need more aggressive anticoagulation. In"catastrophic APLA" plasmapheresis may play a crucial role. Patients who "break through" warfarin should receive heparin.0 Venous Thrombosis: Warfarin to an INR of 3.3. .  Heparin anticoagulation appears more effective.0 .5.3.0 . Arterial Thrombosis: Warfarin to an INR of 2. Inherited Thrombophilia . Inherited Thrombophilia Three important inherited thrombophilias : • Mutation in factor V Leiden causing resistance to activated protein C (responsible of 20–30% of venous thromboembolism events.) • Mutation in prothrombin (guanine 20210 adenine ) • Mutation in methylene tetrahydrofolate reductase (MTHFR) (cytosine 677 thymine (C677T) ) This is responsible for reduced MTHFR activity & is most frequent cause of mild hyperhomocysteinemia & is found in 5–15% of the population. . Factor V Leiden (A506G) mutation  Present in 3-8% of the general population . (heterozygotes) have a seven fold increased risk for thrombosis whereas homozygotes have an eighty fold increase.  It has been linked with an increased risk for venous thromboembolism due to resistance to activated protein C & is responsible of 20–30% of venous thromboembolism events . Protein S deficiency  Protein S deficiency (PSD). present in up to 2% of general population.  Found in 6% of women with obstetrical complications including a relatively high risk for stillbirth. .  Found in approximately 15% of individuals with a DVT or PE . . is associated with a three fold increased risk for DVT or PE. present in 1-4% of the general population.MTHFR (C677T) mutation  A homozygous (MTHFR) mutation. as well as preeclampsia & placental abruption. MTHFR (C677T) mutation  Responsible for reduced MTHFR activity results in decreased synthesis of 5-methyltetrahydrofolate. . the primary methyl donor in the conversion of homocysteine to methionine & the resulting increase in plasma homocysteine concentrations ( Hyperhomocysteinemia ) is a risk factor for thrombosis Dietary restriction of folate & vitamin B12 remains the most common cause. Prothrombin (G20210A) mutation  A change of G to A at position 20210 in prothrombin (prothrombin 20210A) elevates baseline prothrombin levels & thrombin formation. . so no specific treatment could be given. no cause could be found.  However.Unexplained recurrent miscarriage  In about half the women in the research studies. this group responded very well to a programme which removed as many stress factors as possible from their lives. resulting in an 80% success rate with the subsequent pregnancy  Psychological support can improve outcome between the higher areas of the mind & the delicately balanced hormonal system .  After all these investigations 50% of recurrent aborters will have no abnormalities & these should be attributed to chromosomal defect in the conceptus. Women with unexplained recurrent miscarriage have an excellent prognosis for future pregnancy outcome without pharmacological intervention if offered supportive care alone in the setting of a dedicated early pregnancy assessment unit. .  Referral to a tertiary unit as multidisciplinary management is needed for patients with APLA / Thrombophillia  Psychological support  Education & reassurance has an important role to play .Conclusion  In cases of adverse pregnancy outcomes APLA should be kept in mind  Detailed history & tailor investigations  Couple should be counselled together .  The only intervention to have demonstrated benefit is serial ultrasound scans in early months of pregnancy. Thromboprophylaxis for previous thromboembolic episode Risk categoryp High risk TED (thromboembolic disease) Risk factors -Prev. Prophylaxis ANC:s/c UH or LMWH Intrapartum:s/c UH or LMWH Post partum:s/c UH or LMWH for 3-7 days f/b UH or LMWH or warfarin for 3-7 days ANC: g odd Intrapartum or post partum:as above Low risk One prev TED (No other risk factors) . TED -Prev TED+APLA -Prev TED+ family history of TED -Recurrent TED -TED in current preg. and debates among researchers and clinicians concerning which antibodies to measure. . Although multiple APLAs might eventually be considered pathologic to pregnancies. a lack of agreement between laboratories concerning standardization of the assays. anti-cardiolipin. antiphosphotidylserine. Diagnosis of APLA can be challenging. and the 'lupus anticoagulant' are generally believed to be culprits when identified in women with pregnancy losses. due to fluctuating titers of the antibodies. This is an expensive therapy that has less clear-cut efficacy demonstrated. Rx APLA syndrome generally requires daily baby aspirin prior to conception & the use of baby aspirin & heparin as soon as pregnancy is diagnosed  One recently published study demonstrated an 80% success rate for treatment of APLA by this approach. .  More aggressive treatment of APLA occasionally involves the use of human intravenous immunoglobulin. and is not endorsed by the American College of Obstetricans and Gynecologists. The 20% failure rate is likely accounted for in large part by genetically-abnormal losses. The use of empiric intravenous immunoglobulin should generally be discouraged.
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