Anemia in pregnancy - pathophysiology and diagnosis

ANEMIA in pregnancy -pathophysiology and diagnosis

1. ANEMIA IN PREGNANCY DR.A.DIVYA PANI NATCHIAR SENIOR RESIDENT DEPARTMENT OF GENERAL MEDICINE

2. INTRODUCTION Commonest medical disorder in pregnancy. Prevalence:- 10-12% - developed countries - 87.2% - developing countries It is responsible for significant high maternal and fetal mortality rate worldwide.

3. DEFINITION Anemia is a condition in which the number of RBCs or their oxygen carrying capacity is insufficient to meet the physiological needs of the individual , which varies by age, sex, altitude, nutrition, socioeconomic status, smoking, pre-existing iron levels & pregnancy status .

4. Anemia in pregnancy Hb - <11g/dl- 1 st & 3 rd trimester Hb -<10.5 g/dl – 2 nd trimester Asymptomatic initially Symptoms in the later trimester when the demands are high

5. CLASSIFICATION Mild : 9- 10.9 gm /dl Moderate : 7- 8. 9 gm/dl Severe : < 7 gm /dl Very severe : <4 gm /dl

6. CLASSIFICATION OF ANEMIA 1. Physiological Anemia 2. Pathological Anemia Iron deficiency Folic acid deficiency Vitamin B12 deficiency 3. Hemorrhagic Anemia Acute—following bleeding in early months of pregnancy or APH Chronic—hookworm infestation, bleeding piles, etc.

7. 4. Hemolytic anemia Familial—congenital jaundice, sickle cell anemia , etc. Acquired—malaria, severe infection, etc 5. Bone marrow insufficiency Radiation, drugs or severe infection. 6. Hemoglobinopathie s SCA, Thalassemia

8. PHYSIOLOGICAL ANEMIA OF PREGNANCY During pregnancy, maternal plasma volume expands by 50% Starts at 8-10 weeks Maximum around 2 nd trimester Increase in red blood cells is 25%. This relative hemo -dilution – decreses Hb & HCT concentration. Fall in iron stores Even in severe anemia- fetus tolerates it bcoz of high affinity of HbF for oxygen

9. IRON REQUIREMENTS IN PREGNANCY During pregnancy approximately 1000- 1,500 mg iron is needed for:-   Increase in maternal haemoglobin (400-500mg) The fetus and placenta (300-400 mg) Replacemet of daily loss through urine, stool and skin (250mg) Replacement of blood lost at delivery (200mg) Lactation (1mg/day) 

10. IRON REQUIREMENTS Avg Fe intake– 0.8mg/day in 1 st trimester . - 4-5mg/day in 2nd trimester - 6mg/day in 3 rd trimester In pregnancy – iron requirement is 3 times higher Fe stores- 300mg

11. IRON AND FOLIC ACID REQUIREMENT IN PREGNANCY Elemental iron - 30 mg to 60 mg   Folic acid- 400 µg (0.4 mg)  It is  recommended  for   pregnant   women to prevent maternal anemia, puerperal sepsis, low birth weight, and preterm birth of babies.

12. IRON DEFICIENCY ANEMIA 80 % of pregnant women are iron deficienc t Main causes – Menstruation and parturition Recent delivery of less than 1 yr Decreased iron intake Iron content -40mg 15% is absorbed Main sources- RBCs, myoglobin - Transferrin (Minor) - Ferritin ( Major)

13. DIAGNOSIS CBC- - Decreased Hb - Decreased MCV PS – Microcytic hypochromic anemia Iron profile – decreased iron , ferritin, Transferrin saturation But increased iron binding capacity USG

14.   EFFECTS OF ANEMIA ON THE MOTHER I mpaired cell-mediated immunity Intolerant to postpartum hemorrhage Strain ing in labor - cardiac failure PIH P reterm l labour F atigue

15. EFFECTS TO FETUS/ BABY Intrauterine hypoxia and growth retardation Prematurity LBW Anemia a few months after birth due to poor stores Still birth

16. MEGALOBLASTIC ANEMIA   B12 & folate deficiency – impaired DNA synthesis – arrested nuclear maturation Physiological – Decrease in transcobalamin levels Main cause – Dietary deficiency ( green leafy, legumes, animal protein Others – Malabsorption syndromes - Gastrectomy, jejunal resection - Crohns , hemolysis , malignancies - Anti folate drugs

17. DIAGNOSIS CBC- Reduced Hb - Increased MCV PS- Macrocytes - Hypersegmented neutrophils Serum B12 & Folate levels Antibodies to IF & parietal cells

18. ADVERSE EFFECTS Neural tube defects Cardiac septal defects Placental abruption

19. ANEMIA OF CHRONIC DISEASES Inflammatory cytokines restrict erythropoiesis Increased Hepcidin levels Increased ferritin with decreased transferrin levels Causes- CKD , IBD, CTDs -Granulomatous infections & malignancies

20. APLASTIC/ HYPOPLASTIC ANEMIA Grave complication but rare Causes- Immunological disorders . - Drugs & chemicals - Infections - leukaemia, radiation - Inherited – Fanconis anemia - Diamond blackfan anemia - Gauchers disease

21. DIAGNOSIS CBC- Pancytopenia PS Bone marrow biopsy – Acellular / hypocellular Dry tap in case of BM fibrosis

22. ADVERSE EFFECTS Haemorrhage Infections Pre- eclampsia Preterm IUGR Stillbirth

23. HEMOLYTIC ANEMIAS Can be either primary or secondary Autoimmune hemolytic anemia - Cold agglutinins( M.pmeumoniae /EBV) Pregnancy a/w- Transient & mild MAHA with thrombocytopenia HELLP Acute fatty liver of pregnancy PNH – serious complication - VTE

24. PNH Acquired X linked gene- PIG A Chronic hemolysis – mild to lethal/ insidious Triggers- Infections, surgery, transfusions Complications- VTE . -Renal failure -Hypertension -Budd- chiari syndrome

25. DIAGNOSIS OF HEMOLYTIC ANEMIAS DCT / ICT LDH PS- Spherocytes , schistocytes Deranged LFT Warm and cold antibodies R/O infections, malignancies, drug history USG- HSM , Fatty liver PNH workup

26. Hemoglobinopathies SICKLE CELL ANEMIA:- - HbA - 2 alpha & 2 beta globin chains - Glutamate substitution by valine – HbS - Glutamate substitution by lysine – HbC Morbid variants- Hb SS, HbSC , HbSE , HbS /B0/1 Constant Sickling episodes( deO2-nation)- Irreversible sickle cells- sickle cell crisis

27. COMPLICATIONS Overt infections Acute chest syndrome Cardiac dysfunction – LVH –sepsis- failure,PHTN,pre - eclampsia Triggers- Infections - Marrow emboli - Thromboembolism - Atelectasis

28. THALESEMIA SYNDROMES: ALPHA THALASSEMIA:- Deletion of alpha globin chains Silent carriers – single gene deletion Alpha thalassemia minor – 2 gene deletion . - Hbbart (gamma 4) - @ birth– as their levels drop--- they are not replaced by HbH HbH - beta 4 – compound heterozygous . - Hb bart is repaced by HbH HbBart /alpha thalassemia major – still born/ hydrops DIAGNOSIS – Fetal cardiothoracic ratio at 12-13 weeks . - Myocardial performance

29. Beta thalassemia Defective beta globin synthesis Increase in alpha globin chains that precipitate Beta thalassemia minor – Increase in HbA2 Beta thalassemia major/ Cooleys anemia . -fatal - Transfusion dependant

30. Diagnosis DNA analysis Genetic testing – chorionic villous sampling Pre- implantation testing – affected offspring Fetal – capillary electrophoresis - High performance liquid chromatography

31. PERIPHERAL SMEAR - Fe Deficiency – MCHC

32. PS – MEGALOBLASTIC ANEMIA

33. PS- HEMOLYTIC ANEMIAS

34. PS- SICKLE CELL ANEMIA

35. PS- THALASSEMIA

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