4Anemia ANEMIAS OF DECREASED RBC PRODUCTION ANEMIA DUE TO RBC DESTRUTIONDECREASED Hb SYNTHESIS- MICROCYTICIRON DEFICIENCYTHALASSEMIASIDEROBLASTIC ANEMIADECREASED DNA SYNTHESIS- Megaloblastic anemiaSTEM CELL FAILURE – Aplastic anemiaANEMIA OF CHRONIC DISEASEHemolytic anemiaAutoimmuneHemoglobinopathies
5Hemolytic anemiaPremature destruction of RBCs inherited defects/acquired intravascular abnormalities.Hemolysis -Intravascular or extravascularGeneral features of hemolytic anemiaGeneral examinationPallor, jaundiceOther physical findingsSplenomegaly, bossing of skullHemoglobinNormal to severely reducedMCV, MCHUsually increasedReticulocytesIncreasedBilirubinIncreased (mostly unconjugated)HaptoglobinReduced to absentLDHIncreased( upto 10 times with intravascular hemolysis)
8Intravascular destruction of RBCs schistocytesCauses - mechanical trauma,complement fixation,toxic damage to the RBC.Decreased serum haptoglobulin,hemoglobinemiahemoglobinuria,hemosiderinuriaIron loss
10Extravascular destruction of RBCs Causes - bound immunoglobulin, or physical abnormalities restricting RBC deformability that prevent egress from the spleen.Iron overload leading to secondaryhemochromatosis-damage to liver& heart
11Clinical features Lab investigations in hemolytic anemias Due to anemiaWeakness, exhaustion & lassitude, indigestion, loss of appetitePalpitations, giddiness, dyspnoeaPallor, hyperdynamic circulation, flow murmurDue to hemolysisIcterus, splenomegaly in extravascular hemolysis, gall stone diseaseLab investigations in hemolytic anemiasComplete hemogram with reticulocyte count PBS – anemia with reticulocytosis & fragmented RBC on PBSDecreased serum haptoglobulin.LFT/KFTDCTUSG abdomen- HepatosplenomegalyHPLC, Osmotic fragility test
13Membrane disorders-Hereditary spherocytosis MC -northern European ancestryAD, chr 8pDefect- abnormality of ankyrin.Decreased surface area/vol-Spherocytes - less flexible – extravascular hemolysis-splenomegaly.Only condition with increased MCHC.Increased osmotic fragility (Pink test)TT- No tt aimed at cause.Splenectomy – Obligatory .In pregnancy (rare)- fetal loss in 1st trimester, aplastic or hemolytic crisis, increased folic acid requirement due to chronic hemolysisSplenectomy – 2nd trimesterAffected Fetus – neonatal jaundice, need for exchange transfusionPND- by CVS, amniocentesisPrevalance- 1 in 5000.Normocytes, Spherocytes.
14ENZYME DISORDERS- G-6-PD deficiency MC enzyme deficiency .X linked recessiveMediterranean, West African, Mid-East, and Southeast Asian populationsInteraction between extracorpuscular & intracorpucular cause.Heterozygotes - resistant to P falciparum.Oxidative stress- Increased methemoglobin, aggregates of denatured hemoglobn to form heinz bodies, membrane injuryScreening – NADPH mediated dye decolorationDiagnosis – spectophotometric assay of NADPH production, G6PD enzyme assaysG-6-PD reduces NADP to NADPH.NADPH reduces oxidized glutathioneto its reduced form whichprevents oxidative damage
16Contd…….In pregnancy:Spontaneous abortion, still birth & low birth wt babies with neonatal jaundiceAffected fetus – non immune hydrops if mother ingests oxidant drugs crossing the placentaPND- CVS or FBSAvoid agents causing hemolysisAcute hemolytic episode – adequate hydration, maintain urine output, BT if needed*cells where denatured hemoglobin (Heinz bodies) were removed in the spleen]spherocytes, schistocytes, bite cells & blister*
17Pyruvate kinase deficiency Autosomal recessiveReduced ATP formation causes RBC membrane rigidity.PBS- polychromasia, anisocytosis, poikilocytosis with burr cells & acanthocytesSymptoms -usually mild (right shift of the 02-dissociation curve).Homozygote -severe anemia & usually discovered in childhood. Splenomegaly, cholelithiasis and jaundice .In pregnancy – well tolerated, supportive management during crisis & BT if neededSplenectomy – 2nd trimesterFetus– nonimmune hydrops FBS for diagnosis & IUT if needed*Conversion of phosphoenol pyruvate to pyruvate & generation of ATP
18MECHANICAL TRAUMARBCs striking against abnormal surfaces (aortic stenosis, atherosclerosis) or artificial surfaces (prosthetic heart valves; arterial grafts).Microangiopathic hemolytic anemia - RBCs torn apart on fibrin strands strung across small vessels or on damaged endothelial surfaces of small vessels.Accompanies DIC, malignant hypertension, HUS, TTP, pre-eclampsia, and some vascular neoplasms.
20HEMOGLOBINOPATHIES Minor disorders Sickle cell trait- Hb AS Hb SE diseaseHb SD diseaseHb S MemphisMajor disordersSickle cell anemia – Hb SSHb SC diseaseHb S ß thalAbnormalities due to alteration in structure, function or production of hemoglobininherited disorders- autosomal dominant (unstable hemoglobins) and autosomal recessive (Hgb S).The most common are thalassemia and sickle cell disease/trait.
21Sickle cell Disease Qualitative disorder Point mutation in the ß-chain at codon 6 encoding of a valine instead of normal glutamin.Hb S- poorly soluble in low oxygen tension, polymerizes into fibrilary structures/ tactoids-- causing them to become rigid and sickled.M.C inherited hematological disease worldwideMost prevalent in African descent(1 in 625).ACOG technical bullein, no. 185, Oct 1993The term sickle-cell disease is preferred because it ismore comprehensive than sickle-cell anaemia.
22Autosomal recessiveHomozygous/Heterozygous(coinheritance with other abnormal hemoglobin ;mostcommonly HbSC or b thalassemia)Diag -chances (for each pregnancy)of two carrier parents having a child with a sickle cell or thalassaemia disorder.
23If the mother is anemic & the father is healthy carrier 50% of the off springs are carriers and 50% is anaemic
24PATHOPHYSIOLOGY Hemolysis Vaso-occlusion-because of- a)sickled cells are less deformable& more fragile & also have increased tendency for cellular dehydrationb) Increased adhesion of red cells to vascular endothelium(increased expression of adhesion molecules, upregulation of thrombotic pathways, proinflammatory state)Life span of sickle cells – 17 dInitially, oxygenation restores normal shape.With repeated cycles of agglutination & polymerisation, sickling becomes irreversible
26Diagnosis Isoelectric focussing HIGH PRESSURE LIQUID CHROMATOGRAPHYIsoelectric focussingCellulose acetate electrophoresis at alkaline pHCapillary electrophoresisSickle cell solubility test- Widely used screening method.Relies on the relative insolubility of Hgb S in concentrated phosphate buffers compared to Hgb A and other Hgb variants. Hgb S precipitates causing a cloudy solution.
27Sickle cell traitHgb SA % of the hemoglobin is Hgb S; remainder being Hgb A, Hgb F & Hgb A2.No anemia and normal RBC morphology is the rule.Two rare complications-hematuria and splenic infarction.No risk from anesthesia, surgery, pregnancy, or strenuous physical activity.Normal growth & development, normal life spansIncreased incidence of pre-eclampsia in pregnancy
28Preconceptional care General advice & care - At least annual review at specialist clinic -BP measurement,KFT testing,ophthalmological checkup,screening for red cell antibodies & iron overload*,cardilogy review for pulmonary hypertension( echo not done in last year)Specific issues in women trying to conceive counselling aboutRisk of worsening anemia, increased infections(especially UTI),pain, IUGR, PTL, Pre-eclampsia , caesarean section & perinatal mortality.Role of dehydration(Early detection & treatment of nausea &vomiting), cold, hypoxia, overexertion, &stress in frequency of sickle cell crisis*for women who had multiple blood trandfusions
29ANTENATAL SCREENING Pregnancy Offer screening Negative Result Blood sent to laboratory for haemoglobinopathy ScreenNegative ResultInformation: No further actionPositive resultsInformation & counseling-Offer partner screeningPartner screeningBlood sent to laboratory for haemoglobinopathy ScreenNegative ResultInformation: No further actionPositive results: At risk coupleInformation & counseling-Offer prenatal diagnosisPrenatal diagnosisFetal blood Sampling/ Chorionic Villus samplingUnaffected FetusInformation- No further actionAffected fetus- Information &counselingContinue with PregnancyParents Make- Informed ChoiceTermination of Pregnancy
30Sickle cell disease contd…. Medications-Daily penicillin prophylaxis (250 mg BD)Folic acid 5mg once daily throughout pregnancyHydroxycarbamide should be stopped 3 months prior to conception( termination is not indicated based on exposure to hydroxycarbamide alone).ACE inhibitors & Angiotensin 2 receptor blocker , iron chelating agents should be stoppedNSAID’s are not recommended <12weeks& >28 weeks ; should only be taken after medical advice in 2nd trimester.Vaccinations ( preconceptional)*-H.influenza type b, conjugated meningococcal C vaccine, Hepatitis B , Influenza & swine flu vaccine annually, pneumococcal vaccine every 5 years.*immune status should be determined preconceptually.Management of sickle cell Disease in pregnancy. RCOG2011
31Sickle cell disease contd…. Indications of urgent transfusion therapy ) Acute anemia - top up transfusion,Hb <6 g/dl ora fall of over 2g/ dl orsymptomatic patients.2)Acute chest syndrome& acute stroke – exchange transfusionRole of prophylactic transfusion in pregnancy-Insufficient evidence to draw the conclusion about role of prophylactic blood transfusions in pregnancy.Mahomed K et al. prophylactic versus selective blood transfusion for sickle cell anemia The cochrane library, issue 2.Indicated for women who are on a long term transfusion regime prior to pregnancy.*
32Antenatal care Multidisciplinary team Pregnancy – exacerbations of disease manifestationsincreased metabolic demands,hypercoagulable state,increased vascular stasis –Vaso-occlusive crisis – common in later half of pregnancyPyelonephritis – altered immune system added to renal changes of pregnancySymptomatic cholelithiasis – chronic hemolysis, progesterone induced changes in GITSusceptible to infections, pre-eclampsia,thromboembolismIUGR, preterm labour, abruption,SCREENING – selective (low preevalance area) versus universal(high prevalance area) mainly to diagnose minor forms. If positive, screen partner, genetic counselling, PND
33Antenatal management Early booking ANC Visits monthly upto 24weeks, 2weekly until 36weeks& weekly thereafter.Low dose aspirin (75mg daily )from early pregnancy(12weeks) till 28weeks.Routine thromboprophylaxis only if they have additional risk factors, but should receive LMW heparin during antenatal hospital admission RCOG Reducing the risk of thrombosis in pregnancy & puerperium. Green top guideline 37.Role of iron suplementation:Iron supplementation is withheld unless there is e/o iron deficiency.Akien’ova YA et al. Ferritin & serum iron levels in adult patients with sickle cell anemia in Ibadum, Nigeria. Afr J Med Sci1997;26.
34Contd……….Routine iron supplementation entails a negligible theoretical risk of iron overload for a substantial benefit Streetly A et al, BMJ 2000; 320.BP & Urinalysis at each visit.Serial USG for GP & AFI from 24 weeks; every 4 weekly& more frequently if there is evidence of poor growth.Monthly assessment of hct, reti count, urine c/sFetal monitoring – DFMC, weekly NST & BPPMaintain oral hydration, diagnose & treat infections earlyMode of delivery- In the absence of obstetric indications allow spontaneous labour at termRole of cytotoxic agents to HbF & HbA – 5-azacytidine, hydroxyurea – investigational in pregnancy.`
35Management of acute painful episodes during pregnancy Most frequent complications, incidence- 27%-50%.Mild pain –rest, fluids & simple analgesia(paracetamol& week opoids)Severe pain- low threshold for admitting to hospital.Assess for other complications precipitating factors(Dehydration)Ix-spo2, urinalysis, full blood count, reticulocyte count, KFT, Urine c/s, blood c/s, chest x-ray.Tt- strong opoids- morphine/ diamorphine(oral/parenteral) are the first line agents.Give adjuvant non-opoid analgesia: PCM, NSAIDS(12-28weeks)Monitor for pain score, sedation score, & oxygen saturation using a modified obstetric early warning chart(MEOWS), RR every 20-30minutes until pain is controlled & signs are stable, then monitor every 2 hour or hourly if receiving parenteral opiates.Give rescue dose of analgesia if required.Rees DC et al. Guidelines for the management of acute painful crisis in sickle cell disease.BJH. 2003;120.
36Contd… If RR<10/min, omit maintenance analgesia; consider naloxone Oral/ iv fluids – 60 mg/kg/24 hours.(precaution – PET)Maintain I/o chartAntibiotics & Thromboprophylaxis should be used.Consider reducing analgesia after 2-3days & replacing injections with equivalent dose of oral analgesia.Discharge when -pain is controlled/ improving without analgesia or on acceptable doses of oral analgesia.Rees DC et al. Guidelines for the management of acute painful crisis in sickle cell disease.Br J Hematol 2003;120.
37Intrapartum management Timing of delivery weeks.Mode of delivery- vaginal.Adequate hydrationPulse oxymetry should be used throughout labourSupplemental oxygen therapy used if necessary to maintain spo2 >94%.Antibiotic therapy should be used if there is evidence of, or high clinical suspicion of infection.Continuous fetal monitoringEpidural analgesiaRegional anaesthesia preferred for caesarean section.Hourly vital signs- low threshold to start broad spectrum antibioticsManagement of sickle cell Disease in pregnancy. RCOG2011
38Post partum management Risk of thrombo-embolism, painful crisisEarly ambulation, hydration,pain releif (NSAIDS/pcm/ opoids)Prophylactic sucutaneous LMW heparin for 7 days after vaginal delivery & 6 weeks following a caesarean section.Aggressive treatment of suspected infectionCord blood – HPLCEncourage breast feedingAntithrombotic stockingBaby affected- prophylactic penicillin from 3 months of age- ↓ incidence of pneumonia.Contraception- progesterones are effective & safe contraceptive . First line- PIC, MIRENA, Implanon, pop, barrier method. Second line- COC, Cu- IUD, Vaginal ring , Combined patch.
39THALASSEMIASImbalance of globin chains available for hemoglobin dimer construction.ß thalassemia - defective synthesis of the ß chain.A thalassemia, defective synthesis of the a chain (quantitative).Globin chain (a, b, d, e, g & z) structural genes are located on chromosome 16 (a;z) and chromosome 11 (b;d ; e;g).
40Geographic distribution ß -thalassemia is common in the Mediterranean region, Africa, Asia, the South Pacific, and India.a -thalassemia more common in Southeast Asia.Prevalance- 16% in southern European , 10% in Thiland , 3-8% in Indian , Pakistani & Bangladeshi populationLeung TN et al. Thalassemia screening in pregnancy.Curr Opin Obstet Gynecol 2005; 17.
41ß-Thalassemiapoint mutations or a partial deletions of chromosome 11 cause defective synthesis of the ß chain.( >100 mutations)Normally- a and b globin chains are roughly equal amounts.When ß-globin chains are in short supply or absent, the excess a-chains combine with other available ß-family globin chains ( d or g) to form increased amounts of Hgb A2 (a2d2) & HgbF (a2g2).Hgb Barts( g4) or tetramers of excess gamma chains may form.
42The clinical severity depends on the degree to which production of the ß-chain is inadequate. ß-thalassemia major -no ß chains (ßo) or very little is made (ß+).ß-thalassemia minor -ß+ chains are made in mildly reduced amounts.ß+thalassemia intermedia ß+ chains are made in amounts intermediate to the major and minor forms.Signifcance of ß-gene Mutationtype 1 ß+ - about 10% of normal ß chain productiontype 2 ß+ -about 50% of normal ß chain productiontype 3 ß+ - >50% of normal ß chain production
43ß-Thalassemia majorNo ß chains (homozygous for ßo, Cooley's anemia), or very little ß chain (homozygous for ß+).Hgb electrophoresis-↑ HbF,↑ HbA2, variable amounts of Hb A.PBS - severe anisocytosis& poikilocytosis, targets, elliptocytes, teardropsAsymptomatic till 6 months of life**C/F- severe, transfusion dependent anemia. Nearly all have hepatosplenomegaly.Expansion of the marrow by erythroid hyperplasia - enlargement of bones.Iron overload, secondary to transfusion dependency, results in damage to the heart, liver and endocrine organs.Short life span, most dying before adulthood.**globin production changes from predominantly g -chain to ß-chain.
44ß-Thalassemia minorß-thalassemia trait/ minor- Heterozygous- mildly reduced production of ß+ chains & thus, a mild excess of a globin chains which denature, causing damage to young red cells in the marrow (ineffective erythropoiesis) or decreased survival in the peripheral blood.ß-thal intermedia mb homozygous for type 2 ß+ and type 3 ß+.Mild anemiaHigh Hemoglobin A2 levels are classic. Hb F - mildly increased.Folic acid 1mg/d to be supplementedPBS- microcytic &hypochromic; often withassociated erythrocytosis.Basophilic stippling and reticulocytosis may help to distinguish the b-thal minor & fe def anemia(more common in thalassemia).No ↑ in preterm, IUGR/ LBW, Pacental size,change in fetal-placental weight ratio
45a -ThalassemiaClassical a-thal- deletion from chromosome 16 of a-genes.Less common is point mutations.Exess ß-chains form pairs and combine to form HbH (ß4).Unpaired ß chains precipitate, damages RBC membrane.Severity vary with the number of alpha-chain genes deleted* Hb Constant Spring (mutation of a -chain termination codon causes addition of 31 extra amino acids, resulting in an unstable globin).
46a -Thalassemia One alpha gene deleted- silent carrier state. Two alpha genes deleted-homo/heterozygous a -thalassemia trait.a-thalassemia trait - microcytosis, hypochromia, & mild anemia. Normal HbA23 genes deleted:( - - /-a) hemoglobin H is produced (four ß chains) - unstable & precipitates in vivo causing hemolysis. Crystal violet/new methylene blue supravital stains- Heinz bodies (precipitated Hgb H).All 4 genes deleted- Bart's hemoglobin-tetramer of g chains - hydrops fetalis- death in utero - encountered in people of Asian and African ancestry.The heterozygous type common in Southeast Asian populations, but is rare in Afro-Americans.
47Thalassemia screening Incidence- very high, with over 30 million people carrying the defective gene. Carrier frequency varies from 3 to 17% in different populationsOver 9000 thalassemic children born every year & treatment is very expensiveCarrier screening program offers genetic counselling, PND and selective termination of affected fetuses.Various options available are:Screening of school going children;Screening of high risk communities;Premarital screening;Extended family screening - screening of relatives if there is a thalassemic child in a faimly; andRoutine antenatal screening in early pregnancy ideally between weeks(Most faesible)Menon P.S.N et al, dept of paeds, AIIMS
48Methods of Antenatal screening RBC indices:MCV (<77 fl) and MCH (<27 pg) with sensitivity98% and specifity92%.NESTROFT: Positive test is due to the reduced osmotic fragility of red cells .sensitivity – 91%, specificity-95%, ppv-55% & npv-99%.Raised Hb A2 level >3.5%: Gold standardMethods- Microcolumn chromatography, HPLC and capillary isoelectrofocusing.16% of ANC were positive by NESTROFT& RBC indices. However, only 4.5% wereconfirmed by HbA2Unpublished data, ICMR project, dept of paeds, AIIMS
50contd When MCH/MCV is low, check both hb pattern & iron status. HPLC- HbH inclusion bodies – diagnostic of alpha thalassemia trait.Beta thal trait – HbA2 &HbF both are elevated.False negative- carrier of both alpha & beta thalassemia, associated iron deficiency. Therefore a normal Hb pattern in presence of iron deficiency can not exclude a co-existing thalassemia trait. A repeat HPLC after correction of iron deficiency should be done.
51Non-invasive prenatal diagnosis Unlike beta- thalassemia, alpha thalassemic fetuses present from early gestation with anemic signs ; detectable on USG: safe alternative in prenatal diagnosis.USG surveillance for couples with alpha thalassemia – cardiomegaly, thickened placenta, increased MCA-PSV, & Hydropic changes.CTR is the best marker in first trimester.Between weeks –using CTR 50% or greater as cut off, Sn 97.5%, Fp 9.1%. Placental thickness ≥ 18mm- Sn- 71%. Fp- 19%.2nd trimester- CTR is still the best marker( Sn -100%, Fp-5.9%.Leung KY et al.Ultrasonographic prediction of homozygous alpha thalassemia using placental thickness, fetal CTR, MCA doppler: alone or in combination? Ultrasound Obstet Gynecol2010;35.
52Noninvasive prenatal diagnosis for couples with beta thal USG- Not applicableAnalysis of circulating fetal nucleic acid in maternal plasma- most specificabsence of paternal mutation in maternal plasma excludes beta thal major & invasive testing can be avoided.presence of paternal mutation in maternal plasm- 50% risk of beta thal major; invasive testing needed.(Disadv- father & mother must carry different mutation)When dealing with other paternally inherited beta-gene defect involving point mutation, allele specific/ single allele extension reaction followed by mass spectrophotometry.Lo YM et al. Noninvasive approaches to prenatal diagnosis of hemoglobinopathies using fetal DNA in maternal plasma.Hemaatol Oncol Clin North Am 2010; 24.
53Digital PCR combined with fetal DNA enrichment strategy- Allelic ratio-1:1-carrier, >1- fetus homozygous for mutation, <1- fetus has not inherited any mutation Lun et al.Noninvasive prenatal diagnosis of prenatal monogenetic disease by digital size selection and relative mutation doses on DNA in maternal plasma. Prac Natl Acad Sci U S A 2008;105.Most recent- application of massively parallel DNA sequencing technologies in cell free fetal DNA in maternal plasma Lo YM et al. Maternal plasma DNA sequencing reveals the genome-wide genetic & mutational profile of fetus. Sci Transl Med 2010;2.Pre-implantation genetic diagnosis- cleavage stage biopsy is better than polar body / blastocyst biopsy Petrou et al.Preimplantation genetic diagnosis. Hemoglobin 2009; 33:s7-s13
54Maternal health & Obstetric outcome Assessment &management of pre-existing complicationsCardiac effectsEndocrine problemsAlloimmunisationAssessment & treatment of viral infectionsHypercoagulable state & thrombosisEffect of hemolysis & depletion of nitric oxideOsteopaenia, osteoporosis & bone deformityPre-pregnancy assessment & management.
55Beta- thalassaemia major & intermedia Spontaneous miscarriage & fetal loss- 9%-33%.Preterm birth- increasedMultiple pregnancy- higher incidenceFetal growth restriction-increased because of maternal anemia & reduced oxygen supply.Obstetric complications- gestational hypertension & pre-eclampsia (most frequent; 2.5%- 20%); gestational diabetes (10-20%); placental abruption(3.8%-6.7%); UTI(3.8%)Maternal cardiac failure-1.1%-15.6%Caesarean delivery- high(high rate of CPD, maternal short stature, oseopaenia/ osteoporosis & maternal HIV infection,low threshold for caesarean delivery**owing to previous nature of pregnancy & uncertainity of future fertility.
56Contd……..Maternal anaemia and transfusion of red blood cells- target Hb-10gm/dlProphylaxis for thromboemboism- no specific regime. Acetylsalicylic acid antenatally for women who have undergone splenectomy & postpartum LMW heparin.Thalassaemia trait-Screening for fetal congenital anomalies, especially neural tube defects-in alpha & beta thalassaemia carrier anencephaly was more common(OR 3.99).Lam YH et al.Risk of neural tube defects in offspring of thalassaemia carriers inHongcong Chinese. Prenat diag 2006.Tong et al. C-reactive protein & insulin resistance in subjects with thalassaemia major &family history of diabetes. Diabetes Care 2002; 25.
57Contd…… Antanatal complications- Gestational glucose intolerance-markedly increased.Mechanism-increased insuline resistance in liver & muscle,low grade hepatic inflammation ,increased oxidative stress secondary to hepatic damage from the increased iron owing to low grade hemolysis.Antanatal complications-IUGR(OR 2.4)Oligohydroamnios (OR 2.1)Hydrops fetalis & mirror syndrome- can result as a result of hemoglobin Bart’s disease & non-deletional form of hemoglobin H disease.Origa R et al. Pregnancy and beta thalassaemia: an Italian multicenter experience.Hematologica 2010; 95.
58Autoimmune hemolytic anemia Most common form of aquired hemolytic anemia( exept where malaria is endemic)Autoantibody directed against red cellsTriad- abrupt onset, jaundice, splenomegaly.Coomb’s test- Positive- clinches diagnosis; Negative- diagnosis unlikely.Two types: a) IgG or "warm" type (optimally active at 37oC)b) IgM or "cold" type (optimally active at 4oC)Treatment- 1st line- Glucocorticoids- prednisone- 1mg/kg/daySecond line- low dose prednisone, azathioprine, cyclosporine.Severe acute AIHA- blood transfusion
59Cold AIHA IgM Ab, optimally active at 4oC Causes - Iymphoma, Mycoplasma pneumonia& rarely infectious mononucleosisIgM- C3 complex fixation on the RBC surface at 28-31oC.RBC agglutination and hemolysis in acral cold exposed areas of the body.Intravascular hemolysisDetected by the DCT.PBS-agglutination of RBCs (room temperature).Antibody does NOT cross placenta, fetus is NOT affected
60Warm AIHA IgG antibodies against RBC surface Ag (active at 37°C). Causes- Non-Hodgkin's Iymphomas, Hodgkin's disease, autoimmune disorders (rheumatoid arthritis; SLE)& drugs (methyl dopa)PBS - Prominent spherocytosisPositive DCT (direct Coombs' test).Treatment ( warm or cold):1) treatment of the underlying disease,2) discontinue offending drugs, &3) corticosteroids (Prednisone).Antibody may cross placenta & affect fetusThe DAT detects antibodies attached to the patient's RBCs.
61Paroxysmal nocturnal hemoglobinuria Clonal disorder of gene (PIG-A) encoding GPI anchorProteins requiring GPI anchor to attach to the RBC membrane are deficient - DAF, C8-bp, MIRL.Bone marrow - usually cellular with marked to massive erythroid hyperplasia, with mild to moderate dyserythropoietic featuresIron deficiency - chronic loss of iron in urine.Blood instead of urineMost consistent- anemia.( m.b Pancytopenia).Hypercoagulable state- venous thrombosis (Budd chiari syn – MC cause of death)Gold standard- Flow cytometry( CD59-, CD55-)Rx- Allogenic BMT ; eculizumab.RBC are protected from complement attack by C3 inactivating proteins: DAF, C8-bp, & MIRL
62Pregnancy & PNHFertility is low, 15 pregnancies reported in 10 patients- 5 SA, 10 reached viability- good outcome? Prophylactic washed RBC transfusionsFolic acid supplementation(3 mg/day)Steroids to ↓hemolysis in acute episodeBT may be neededBMT, androgens – No role in pregnancyPostpartum thrombotic events are common & complete anticoagulation with warfarin is needed
63Aplastic anemiaFailure of pluripotential stem cells to produce RBC, WBC, platelet.pancytopenia + hypocellular bone marrow& absence of underlying malignant/myeloproliferative disease.Severe aplastic anemia- pancytopenia with two of these-ANC< 500/ dl,Platelet count< 20,000/dl&Anemia with Reticulocytes < 1% ,with either bone marrow cellularity<25% or cellularity >50% with <30% hematopoietic cells.Pure red cell aplasia- progenitor cell of BFU-E is affected.Incidence- 2 cases per million(Europe)Diagnosis & treatment of aquired aplastic anemia. Hematol oncol clin N Am 2009,Choudhary vp et al. Pregnancy associated aplastic anemia –a series of 10cases with reviewof literature. Hematology 2002.
64Aplastic anemia Maternal mortality- 20-50% Pregnancy- increased placental lactogen, erythropoietin & estrogen. Placental lactogen & erythropoietin stimulates erythropoiesis estrogen supresses bone marrow. Pregnancy exacerbate the bone marrow depression – if so, terminate pregnancy; else supportive treatmentMaternal mortality %Cause of death- Hemorrhage & infection.Women who survive pregnancy –associated aplastic anemia , 50-70% achieve spontaneous remissionPregnancy with aplastic anemia serious condition.Choudhary vp et al. Pregnancy associated aplastic anemia –a series of 10cases withreview of literature. Hematology 2002;7.
66Aplastic anemia & pregnancy MaternalAntenatal complications-Preterm birth- 12.1%IUD- 16.7%Stillbirth- 15.1%Spontaneous miscarriage- 16.7%Intrapartum- Risk of hemorrhage during deliveryPostpartum- risk of hemorrhage & infection.Fetal- IUGR, IUD, Fetal thrombocytopenia, rarely gangrene of fetal intestine.Kown et al. Supportive management of pregnancy associated aplastic anemia.Int J Gynecol Obstet 2006.
67Treatment Supportive therapy- Most important Repeated blood transfusion to maintain Hb>8 mg/dlPlatelet transfusion yo maintain platelet count > 20,000/mcl.WBC transfusion can be considered in case of fulminating infectionAntibiotic & barrier nursing.Early stages -First line therapy - erythropoietin &GM-CSF.If it fails - thymocyte gamma globulin & cyclosporineG-CSF & GM-CSF can be used in for neutropenia/infectionBMT- Most effective . 5 year survival rate 70-80%BMT is contraindicated in pregnancyAndrogen is relatively contraindicated.Cyclosporine- 300mg/day. GMCSF- 450 mcg i/v biweekly.Deka D et al. Pregnancy associated aplastic anemia: Maternal & fetal outcome. J ObstetGynecol Res 29, 2003.
68ANEMIA OF CHRONIC DISEASES Underlying disease - inflammation, infection, or malignancyusually mild(Hct 30-40%)normochromic/normocytic, Occ mildly hypochromic/microcyticLow serum iron, normal or low transferrin, low transferrin saturation, and high serum ferritin. Bone marrow iron stores are usually increased.Ferritin(acute phase reactant)- elevated in inflammation.Primary mechanism - decreased red blood cell production.Inflammatory and infectious disorders release factors (IL-1, tumor necrosis factor) that suppress erythropoiesis.*Treatment of the underlying disease.Inappropriately low serum erythropoietin levels for the degree of anemia. Human recombinant erythropoietin (EPO) therapy can correct the anemia in such cases.*IL-1 causes the release of lactoferrin from neutrophils. Lactoferrin binds Fe more avidly than transferrin and thus may shunt Fe to macrophages rather than to erythroid precursors. Abnormalities of Fe mobilization from marrow stores are also recognized which may prevent reutilization of Fe salvaged from dead RBCs.
69Thrombocytopenia Platelet count below 1lakh Affects 10% of all pregnanciesPlatelet count decreases by 10% in normal pregnanciesMostly physiologicMost common causes-Gestational thrombocytopenia(70%), preeclampsia(21%),ITP(3%)& others(6%)Mild thrombocytopenia- PC >65000/mcl: 65% have no associated pathology.Paula L et al.Thrombocytopenia in pregnancy. Hematol Oncol Clin N Am 25 (2011)
70ITP Immune Thrombocytopenia Diagnosis of exclusion Incidence per 1000 pregnanciesMost common cause of isolated thrombocytopenia in 1st & early 2nd trimester.Pathogenesis:Immune mediated decreased platelet productionAutoantibody platelet destructionNugent D. Pathogenesis of chronic immune thrombocytopenia: increased platelet destruction&/or decreased platelet production. Br J Hematol 2009;146.
71ITPH/o- easy bruisability, epitaxis, petechiae, menorrhagia before pregnancy, thrombocytopenia in prior pregnancy,PBS- Thrombocytopenia with an increased mean platelet volume & normal red cell morphology.Lab ix- CBC, Reticulocyte count, PBS, Coagulation screen, LFT, & Virology screen including Hepatitis C.Exclude spurious thrombocytopeniaOthers- Kft, DCT, TFT, autoimmune profile, antiphospholipid antibodies.Bone marrow biopsy-indicated in minority of cases only.**s/s suggestive of concomitant bone marrow pathology, following lack of response to adequate treatment, or prior to splenectomy.
72Causes of maternal thrombocytopenia Isolated thrombocytopeniaAsso with systemic disorderSpuriousGestationalPrimary ITPDrug induced- alcohol, Consumption of quinine( tonic water), exposure of environmental toxin.Congenital – Thrombocytopenia absent radius syndrome, Radioulnar synostosis, wiskott Aldrich syndrome, Bernard -Soulier syndrome, Type Iib VWD.Preeclampsia & HELLP syndromeAcute fatty liverHUSTTPSLEThyroid diseaseAntiphospholipid syndromeDICViral infection- HIV, EBV, CMV, HBV, HCV.Folate deficiencyHypersplenismCoincidental marrow disease- MDS, Leukemia, Aplastic anemia
73Gestational thrombocytopenia Commonest cause of thrombocytopenia in healthy pregnant womenFeatures-Tendency to recur in each pregnancy(20%),typically in 2nd trimester,Platelet count remains > 70,000/L,Neonatal platelet count remains normal, &Postpartum platelet count returns to normal within 7 days.PBS- No abn.No associated increased incidence of maternal bleedingNo indication for therapySankaran & Robinson. ITP & Pregnancy. Obstetric medicine 2011.
74Management of ITP in pregnancy Preconceptional counsellingAntenatal management- Team work.Treatment to be initiated when platelet count falls < /mcl.Asymptomatic & PC>50000/mcl- No treatment required.< 50000/mcl & symptomatic- treatment to be considered.>50000 but< Consider treatment if – neuaxial anaesthesia/ analgesia or elective LSCS due to obstetric indication is to be considered.Neuraxial anaesthesia/ analgesia-contraindicated if platelet count <50000/mcl.Caesarian delivery is safe if platelet count is > 50000/mcl.Platelet count deemed safe to consider neuraxial anaesthesia remains controversial.(risk of epidural hematoma formation)Provan D et al. International consensus report on the investigation & management of primary ITP.Blood 2010; 115.
75Management of ITP in pregnancy First line therapy-Corticosteroids- oral prednisolone 1mg/kg once daily ; initial response 3-7 days & maximal response in 2-3 weeks.MOA- To block antibody production& to reduce phagocytosis of antibody-coated platelets by RE system in the spleen.Fetal s/e- risk of cleft palate 3 per 1000.Maternals/e- Hyperglycemia, hypertension, immunosuppression, osteoporosis on long term useLactating mother – low dose <30mg/day appears safe.*Baseline immunoglobulin profile to exclude a common variable immunodeficiency prior to a trial of steroid is recommended.*risk of neonatal adrenal suppressionProvan D et al. International consensus report on the investigation & management ofprimary ITP. Blood 2010; 115.
76Contd……Immunoglobulin- 2 g/kg iv divided over 2-5 days. Adv- rapid response,Disadv- transient response(1-4 weeks), expansive, risk of pathogen transmission, infusion reaction, aseptic meningitis, hedache.Second line options- combination therapy with high dose methylprednisolone combined with Ivig in refractory cases. Azathioprine 2mg/kg, in refractory cases(disadv- delayed response- 6-8 weeks). Splenectomy – rarely needed.Platelet transfusion is NOT indicated exept- severe hemorrhage, immediately before surgery/ delivery.**owing to very short period of response in platelet count.Provan D et al. International consensus report on the investigation & management ofprimary ITP. Blood 2010; 115.
77ITP in pregnancyMode of delivery – guided by obstetric need. Vaginal delivery preferred kelton et al.Idiopathic thrombocytopenic purpura complicating pregnancy. Blood Rev 2002; 16.Instrumental delivery should be avoidedManagement of unexpected delivery, emergency intervention or hemorrhage- combination of high dose intravenous methylprednisolone 0.5-1g daily for 2-3 days & 2g/kg total dose iv ig over 2-3 days with/ without platelet support& oral/iv tranexamic acid.
78Contd…..Postpartum-Maternal- NSAIDs & IM injections to be avoided PC>50000& absence of bleeding elsewhere - thromboprophylaxis to be considered.Neonatal-cord blood platelet count ( if low, confirm it by venous sample)If PC < at delivery –oral vit-k 2mg at birth, 2mg at one week, 2mg at 1 month(instead of im vit k).Transcranial USG,Alternate day platelet count.If hemorrhage is evident/neonatal platelet count is <20000, treatment is ivig 1g/kg infusion; repeated if necessary. Platelet support may be needed.*nadir 3-5 days following deliverySankaran & Robinson. ITP & Pregnancy. Obstetric medicine 2011.
80Prenatal diagnosis for carriers of haemophilia Prenatal testingTimings(weeks POG)Risk of miscarriage(%)CommentsNon-invasive determinations of fetal genderffDNA≥6-8Weeks-----Currently only available in certain centresUSG11-14WeeksFirst- trimester USG fetal sexing available at certain centresPrenatal diagnosis of haemophiliaUnder researchCVS11-141-2Known causative mutationAmniocentesis≥15weeks1Cordocentesis18-2oCausative mutation unknown
81Hemophilia contd…. Antenatal- PND- fetus affected; consider for MTP. assess factor level at booking, 28weeks& at 34weeks POG. Consider for planned delivery.Intrapartum- prophylactic cover is recommended for women with Vwf, FVIII, FIX levels <50iu/dl at term, & they should be maintained above this level for at least 3 days after vaginal delivery / 5 days after caesarean section.Delivery by least traumatic method; Meticulous hemostasisNo invasive fetal monitoringPostpartum- risk of PPHNeonatal- Cord blood sample to assess coagulation status & clotting factor level.
82Pregnancy can be a time of significantly increased morbidity & mortality in women with hematologic disease; however, with careful planning & preparation, most women can be cared for safely, resulting in“Healthy Mother& Healthy Child”