LABORATORY DIAGNOSIS OF LABORATORY DIAGNOSIS OF ANAEMIA IN PREGNANT ANAEMIA IN PREGNANT

WOMENWOMEN

ANNETTE MOBITANNETTE MOBITB.M.L.S (HONS.)B.M.L.S (HONS.)

LABORATORY SCIENTISTLABORATORY SCIENTISTMEDICAL AND HEALTH SERVICESMEDICAL AND HEALTH SERVICES

CDCCDC

INTRODUCTIONINTRODUCTION• A knowledge of a patient’s symptoms and A knowledge of a patient’s symptoms and

clinical history can often establish the clinical history can often establish the cause of anaemia.cause of anaemia.

• Laboratory tests can help to identify the Laboratory tests can help to identify the type of anaemia and monitor patient’s type of anaemia and monitor patient’s response during treatment.response during treatment.

• Techniques for measuring haemoglobin Techniques for measuring haemoglobin and assessing anaemia will also depend and assessing anaemia will also depend on available faculties and resources the on available faculties and resources the Laboratory has in place.Laboratory has in place.

TECHNIQUES FOR TECHNIQUES FOR DIAGNOSINGDIAGNOSING

ANAEMIA IN PREGNANCYANAEMIA IN PREGNANCY • Haemoglobin Measurement.Haemoglobin Measurement.

• Packed cell volume (haematocrit) Packed cell volume (haematocrit) measurementmeasurement

• Red cell indicesRed cell indices

• Blood films ExaminationBlood films Examination

• Electrophoresis to detect Haemoglobin Electrophoresis to detect Haemoglobin sickle cells.sickle cells.

• Reticulocyte countReticulocyte count

• Platelet countPlatelet count

DIAGNOSIS CONTDIAGNOSIS CONT..

•Platelet countPlatelet count

•WBC countWBC count

•Stool examination.Stool examination.

•UrinalysisUrinalysis

Haemoglobin MeasurementHaemoglobin Measurement

• Anaemia occurs when the conc. of Hb Anaemia occurs when the conc. of Hb falls below what is normal for a falls below what is normal for a person’s age, gender and environment. person’s age, gender and environment. Hb values are expressed in grams per Hb values are expressed in grams per litre (g/dl) or grams per decilitre (g/dl). litre (g/dl) or grams per decilitre (g/dl). Hb reference range will also depend on Hb reference range will also depend on the method used, manufacturer’s the method used, manufacturer’s produces and reference range.produces and reference range.

Hb Normal reference Hb Normal reference rangesranges

• Children at birth Children at birth 13.5-19.5g/dl.13.5-19.5g/dl.

• Children (2-5) yrsChildren (2-5) yrs 11.0-14.0g/dl.11.0-14.0g/dl.

• Children (6-12)yrsChildren (6-12)yrs 11.5-11.5-15.5g/dl.15.5g/dl.

• Adult menAdult men 13.0-180g/dl.13.0-180g/dl.

• Adult womenAdult women 12.0-15.0g/dl.12.0-15.0g/dl.

• Pregnancy women Pregnancy women 11.0-13.8g/dl.11.0-13.8g/dl.

Measurement TechniquesMeasurement Techniques

• Haemoglobin can be measured using two Haemoglobin can be measured using two techniques.techniques.

• Photometric Techniques.Photometric Techniques.• Here the absorbance of Hb in blood sample Here the absorbance of Hb in blood sample

is measured electronically using filter is measured electronically using filter colorimeter or read out Hb meter.colorimeter or read out Hb meter.

• Visual comparative Technique Visual comparative Technique This is use when it is not possible to This is use when it is not possible to measure Hb accurately using a measure Hb accurately using a photometric techniquephotometric technique

e.g -Who Haemoglobin colour scale.e.g -Who Haemoglobin colour scale.Sahli’s method (less reliable).Sahli’s method (less reliable).

Packed cell volume (PCV) or Packed cell volume (PCV) or Haematocrit MeasurementHaematocrit Measurement

•Packed cell vol (PCV) is the Packed cell vol (PCV) is the proportion of whole blood proportion of whole blood occupied by red cells occupied by red cells expressed as a ratio PCV is expressed as a ratio PCV is also used to calculate red cell also used to calculate red cell indices, which are also used to indices, which are also used to investigate anaemia. investigate anaemia.

PCV VALUESPCV VALUES

•Pcv values vary according to age, Pcv values vary according to age, gender and attitude, pcv is gender and attitude, pcv is measured in litre.measured in litre.

•Children at birth Children at birth 0.44-0.54l/l0.44-0.54l/l

•Children (2-5) yrsChildren (2-5) yrs 0.34-0.40l/l0.34-0.40l/l

•Children (6-12)yrsChildren (6-12)yrs 0.35-0.45l/l0.35-0.45l/l

•Adult menAdult men 0.40-0.54l/l0.40-0.54l/l

•Adult womenAdult women 0.36-0.46l/l0.36-0.46l/l

Measurement of Red cell Measurement of Red cell indicesindices..

• Red cell indices frequently used to Red cell indices frequently used to investigate anaemia are:investigate anaemia are:

• Mean cell haemoglobin conc.(MCHC). Mean cell haemoglobin conc.(MCHC).

• This gives the conc of Hb in gll in 1litre of This gives the conc of Hb in gll in 1litre of packed red cells. That is calculated from packed red cells. That is calculated from Hb and Hb and

PCVPCV

• MCHC = MCHC = Hb Hb (g/l)(g/l)

• Pcv Pcv (l/l). (l/l).

• Normal Range – 315-360gll (31.5-36.0)gldl.Normal Range – 315-360gll (31.5-36.0)gldl.

MCHC, MCVMCHC, MCV

• Mean red cell volume (MCV)-This gives Mean red cell volume (MCV)-This gives the red cell size. It is determined from the red cell size. It is determined from PCV and electronically obtained RBC PCV and electronically obtained RBC count.count.

• MCV = MCV = PCVPCV L/L L/L = MCV fl.= MCV fl.RBC x 10RBC x 101212/L fl= 10/L fl= 10-15-15 /L /L

• Mean cell haemoglobin (MCH) –This Mean cell haemoglobin (MCH) –This gives the amount of Hb in an average gives the amount of Hb in an average red cell. It is determined from the Hb red cell. It is determined from the Hb and RBC.and RBC.

• MCH = MCH = HbHb g/L g/L = MCH pg= MCH pg RBC x 10RBC x 101212/L pg = 10/L pg = 10-12-12 /L /L

EXAMINATION OF BLOOD FILMSEXAMINATION OF BLOOD FILMS

• This include thin blood films from finger This include thin blood films from finger pricking or bone marrow smear. pricking or bone marrow smear.

• Examination using thin blood films is Examination using thin blood films is important in the investigation and important in the investigation and management of anaemia which produce management of anaemia which produce changes in the appearance of red blood changes in the appearance of red blood cells and differential white cell count.cells and differential white cell count.

• Analysing thin blood film includes the Analysing thin blood film includes the following:following:

EXAMINATION OF BLOOD FILMS EXAMINATION OF BLOOD FILMS CONT.CONT.

• Differential white cell count and white cell Differential white cell count and white cell morphology.morphology.

• Red cell morphology.Red cell morphology.• Platelets.Platelets.• A differential white cell count provides A differential white cell count provides

information on the different white cells in the information on the different white cells in the circulating blood, That iscirculating blood, That is

• Neutrophils Neutrophils • LymphocytesLymphocytes• MonocytesMonocytes• Eosinophils Eosinophils • Basophils (rarely seen).Basophils (rarely seen).

Differential WBC reference Differential WBC reference range for adults.range for adults.

• CellsCells Percentages Percentages

• Neutrophils_______________40-75Neutrophils_______________40-75 %%

• Lymphocytes______________21-40Lymphocytes______________21-40

• Monocytes________________ 2-10Monocytes________________ 2-10

• Eosinophils________________ 1-6 Eosinophils________________ 1-6

• Basophils_________________ 0.1-1Basophils_________________ 0.1-1

ChildrenChildren

CellsCells PercentagesPercentages

• Neutrophils_______________20-45Neutrophils_______________20-45

• Lymphocytes______________45-70Lymphocytes______________45-70

• Monocytes________________ 2-10Monocytes________________ 2-10

• Eosinophils________________ 1-6 Eosinophils________________ 1-6

• Basophils_________________ 0.1-1Basophils_________________ 0.1-1

%

Red Cell AppearanceRed Cell Appearance

Size and ShapesSize and Shapes..• Normocytic – Normal red cell measuring Normocytic – Normal red cell measuring

about 8Nm in diameter.about 8Nm in diameter.• Microcytic – smaller than normal red cells Microcytic – smaller than normal red cells

having diameter less than 6.5Nm seen in having diameter less than 6.5Nm seen in iron deficiency anaemia.iron deficiency anaemia.

• Macrocytic – Larger than normal red cells Macrocytic – Larger than normal red cells with diameter greater than 8Nm seen in with diameter greater than 8Nm seen in Folate, vit B12 def anaemia.Folate, vit B12 def anaemia.

• Sphecrocytosis – small densely staining Sphecrocytosis – small densely staining spherical red cells with no central pallor spherical red cells with no central pallor seen in haemolytic anaemia’s. seen in haemolytic anaemia’s.

Red Cell Appearance Cont.Red Cell Appearance Cont.

• Anisocytosis – unequal variation in the size Anisocytosis – unequal variation in the size of red cells. Seen in many anaemia’s.of red cells. Seen in many anaemia’s.

• Pencil cells – Elongated narrow red cells Pencil cells – Elongated narrow red cells seen in iron deficiency anaemia.seen in iron deficiency anaemia.

• Sickle cell – Elliptical cells with pointed Sickle cell – Elliptical cells with pointed ends or cresent shaped or boat shape ends or cresent shaped or boat shape cells. Seen in sickle cell anaemia.cells. Seen in sickle cell anaemia.

• Schistocytes – Irregularly contracted red Schistocytes – Irregularly contracted red cell fragments often with projections cell fragments often with projections

• seen in red cell damage due to burns, seen in red cell damage due to burns, drugs, toxins, uraemia, and pre-drugs, toxins, uraemia, and pre-eclampsiaeclampsia

Red Cell Appearance Cont.Red Cell Appearance Cont.

• Poikilocytosis – significant variation in cell Poikilocytosis – significant variation in cell shape seen in many anaemia’s.shape seen in many anaemia’s.

• Reticulocytes (Nucleated Red cells)- Reticulocytes (Nucleated Red cells)- Nucleus in red cell seen in sickle cell Nucleus in red cell seen in sickle cell diseases. diseases.

• Megaloblast – Larger than normal red Megaloblast – Larger than normal red cells between (10-20) Nm with an cells between (10-20) Nm with an immature nucleus with fine lacy immature nucleus with fine lacy chromatin pattern. seen in megaloblastic chromatin pattern. seen in megaloblastic anaemia (def of folate or B12).anaemia (def of folate or B12).

Colour of Red blood cell Colour of Red blood cell (Haemoglobinization).(Haemoglobinization).

• Hypochromic – Pale staining red cells Hypochromic – Pale staining red cells with increased area of central pallor.with increased area of central pallor.

seen in ferrus def anaemia.seen in ferrus def anaemia.

• Polychromasia – Blue –grey staining Polychromasia – Blue –grey staining of immature red cells which are of immature red cells which are larger thanlarger than

normal red cells. Seen in normal red cells. Seen in haemolytic haemolytic anaemia.anaemia.

Platelets countPlatelets count

• This can be requested to investigate This can be requested to investigate mucosal bleeding with a decreased in mucosal bleeding with a decreased in platelet count usually below platelet count usually below 20x1020x109 /L

• Normal value 150-400x10Normal value 150-400x109/L/L

• An increased in platelets count can An increased in platelets count can be seen in iron def anaemia be seen in iron def anaemia associated with active bleedingassociated with active bleeding

White Blood cell countWhite Blood cell count

• can be used to investigate infections can be used to investigate infections Normal range in pregnancy 4-15x10Normal range in pregnancy 4-15x1099 /L /L

• leukopenia (decrease in WBC) can be leukopenia (decrease in WBC) can be seen in -Aplastic anaemia,seen in -Aplastic anaemia,

• Folate and vit B12 deficiency Folate and vit B12 deficiency (megaloblastic anaemia).(megaloblastic anaemia).

Other non frequent Anaemia Other non frequent Anaemia investigationsinvestigations

• Stool ExaminationStool Examination..For hook – worm ova. Microscopy for stool For hook – worm ova. Microscopy for stool wet preparation and fecal occult blood test.wet preparation and fecal occult blood test.Severe hook worm infection may lead to Severe hook worm infection may lead to iron deficiency anaemia.iron deficiency anaemia.

Liver function Test Liver function Test Yellowish plasma to detect Bilirubin conc.Yellowish plasma to detect Bilirubin conc.

• UrinalysisUrinalysis Blood in urine is an indication of haemolysis.Blood in urine is an indication of haemolysis.

Summary of red cell indices in Summary of red cell indices in common anaemia’s.common anaemia’s.

MCHC MCHC MCVMCV MCH. MCH.–

Ref value Ref value 31.5-36.0gldl. 31.5-36.0gldl. 80-98fl 27- 80-98fl 27-32pg.32pg.

Anaemias.Anaemias.• NormocyticNormocytic N N N N N N

Normochromic Normochromic

• MicrocyticMicrocyticHypochromicHypochromic e.g Fe def.e.g Fe def.

• MacrocyticMacrocytic N NNormochromicNormochromic e.g Folate Deficiencye.g Folate Deficiency

THANKS

FOR

YOUR

KIND

ATTENTION.