thrombocytopenia during pregnancy

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Thrombocytopenia During pregnancy Prof Aboubakr Elnashar Benha university Hospital, Egypt Aboubakr Elnashar

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Thrombocytopenia during pregnancy

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Page 1: Thrombocytopenia during pregnancy

Thrombocytopenia

During pregnancy Prof Aboubakr Elnashar

Benha university Hospital, Egypt

Aboubakr Elnashar

Page 2: Thrombocytopenia during pregnancy

Causes 1. Spurious result (reduced platelets on automated

Coulter counter {platelet clumping or misreading

of large immature platelets as red cells}

2. Gestational thrombocytopenia

3. Immune thrombocytopenic purpura (ITP)

4. Pre-eclampsia and Haemolysis, Elevated Liver

enzymes and Low Platelets (HELLP) syndrome

5. Disseminated intravascular coagulation (DIC)

Aboubakr Elnashar

Page 3: Thrombocytopenia during pregnancy

6. Haemolytic uraemic syndrome (HUS) /thrombotic

thrombocytopenic purpura (TTP)

7. Sepsis

8. Human immunodeficiency virus (HIV), drugs and

infections (e.g. malaria)

9. Systemic lupus erythematosus (SLE) and

antiphospholipid syndrome (APS)

10. Bone marrow suppression.

Aboubakr Elnashar

Page 4: Thrombocytopenia during pregnancy

Incidence 5-10%: of pregnant women

Gestational' thrombocytopenia:75%

Chronic ITP:

1-2/10,000 pregnancies.

usually affects young Women

female to male ratio = 3:1

Aboubakr Elnashar

Page 5: Thrombocytopenia during pregnancy

AIloimmune thrombocytopenia

fetal disorder

{fetomaternal incompatibility for platelet antigens

(similar to Rhesus haemolytic disease of the

newborn)}

No maternal symptoms and the mother is not

thrombocytopenic.

The condition develops in utero, affects all children

including the firstborn, but is usually (except in the

case of Subsequent siblings) diagnosed after birth.

Incidence: 1 in 2000

causes 10% of all cases of neonatal

thrombocytopenia.

Aboubakr Elnashar

Page 6: Thrombocytopenia during pregnancy

Clinical features Gestational thrombocytopenia:

Benign condition

platelet count <100 x 109/L: no adverse

consequences for mother or baby.

Thrombocytopenia in the first half of pregnancy:

less likely to be gestational: possible diagnosis of

ITP.

Aboubakr Elnashar

Page 7: Thrombocytopenia during pregnancy

ITP

Isolated thrombocytopenia without any associated

haematological abnormality.

No splenomegaly or lymphadenopathy.

Haemorrhage: unlikely with platelet counts >50 x

109/L

Spontaneous haemorrhage without surgery:

unlikely with counts >20 x 109/L.

±skin bruising or gum bleeding

severe haemorrhage: rare.

Aboubakr Elnashar

Page 8: Thrombocytopenia during pregnancy

Pathogenesis Gestational thrombocytopenia

Normal pregnancy: Platelet count fall progressively

5% to 10%: thrombocytopenic levels (50-150 x

109/L) by term.

ITP

Autoantibodies against platelet surface antigens:

peripheral platelet destruction by the

reticuloendothelial system, particularly the spleen.

Aboubakr Elnashar

Page 9: Thrombocytopenia during pregnancy

Diagnosis ITP

By exclusion: other causes (infection and PET)

Bone marrow:

normal or megakaryocytic

not necessary in pregnancy in cases of isolated

thrombocytopenia unless it is severe (platelet count

<30 x 109/L)

Antiplatelet antibody:

not readily available

not helpful {absence of antiplatelet antibodies does

not exclude the diagnosis of ITP.}

Aboubakr Elnashar

Page 10: Thrombocytopenia during pregnancy

Effect of pregnancy on ITP

Pregnancy does not affect the course of ITP

Anxieties arise around the time of delivery

{possible bleeding associated with

vaginal and abdominal delivery and

regional anaesthesia and analgesia}.

Aboubakr Elnashar

Page 11: Thrombocytopenia during pregnancy

Effect of ITP on pregnancy Capillary bleeding and purpura:

unlikely with a platelet count of >50 x 109/L

Spontaneous mucous membrane bleeding:

not a risk with platelet counts >20 x 109/L.

Aboubakr Elnashar

Page 12: Thrombocytopenia during pregnancy

Antiplatelet IgG can cross the placenta: fetal

thrombocytopenia.

Prediction of the fetal platelet count from

maternal platelet count

antibody level or

splenectomy status: not possible

Fetal platelet counts <50 x 109/L:

5% to 10%

10-15% in:

ITP before pregnancy

symptomatic ITP in the index pregnancy.

Aboubakr Elnashar

Page 13: Thrombocytopenia during pregnancy

Antenatal or neonatal intracranial haemorrhage

0% to 1.5%

lowest in the absence of

maternal symptoms or a history of ITP prior to the

index pregnancy.

One of the best predictors of severe neonatal

thrombocytopenia is a previously affected child

Incidence of serious haemorrhage in the fetus and

neonate: low.

Aboubakr Elnashar

Page 14: Thrombocytopenia during pregnancy

Management Gestational thrombocytopenia

Benign condition: no intervention.

Aboubakr Elnashar

Page 15: Thrombocytopenia during pregnancy

ITP

Maternal considerations

Exclude associated conditions:

SLE (ANA, double stranded DNA, smith) or

APS.

The platelet count should be monitored

monthly and then more frequently in 3rd T: therapy

can be instituted if required prior to delivery.

Treatment is only required in 1st and 3rd T:

The woman is symptomatic with bleeding

The platelet count is <20 x 109/L

The count needs to be increased prior to a

procedure such as chorionic villous sampling (CVS)

Aboubakr Elnashar

Page 16: Thrombocytopenia during pregnancy

Counts:

<50 x 109/L (even in the absence of bleeding):

prophylactic treatment prior to delivery.

50 to 80 x 109 /L

may warrant treatment prior to delivery {facilitate

safe regional analgesia}.

Aboubakr Elnashar

Page 17: Thrombocytopenia during pregnancy

CS:

only required for obstetric indications

Epidural and spinal anaesthesia:

safe with stable counts >75 to 80 x 109/L.

Bleeding time does not predict haemorrhage and is

not indicated‘

Aboubakr Elnashar

Page 18: Thrombocytopenia during pregnancy

Corticosteroids:

first-line therapy

Prednisolone dose:

Non pregnant:

(60-80 mg/d, 1 mg/kg/d)

Pregnancy:

lower doses (20-30 mg/d): safe and effective.

then dose may be weaned to the lowest that will

maintain a satisfactory (>50 x 109/L) maternal

platelet count

Aboubakr Elnashar

Page 19: Thrombocytopenia during pregnancy

IV immunoglobulin (IVIg)

Indication:

resistant cases

women likely to require prolonged therapy

women requiring a high maintenance dose of

prednisolone or

who are intolerant of prednisolone.

Mechanism:

delaying clearance of IgG-coated platelets from the

maternal circulation.

Aboubakr Elnashar

Page 20: Thrombocytopenia during pregnancy

Response:

more rapid (24-48 h) than with steroids: useful if a

rapid response is required.

lasts for two to three weeks

Disadvantages:

Expensive

seldom produces long-term remission.

Dose:

0.4 g/kg/ day for five days or 1 g/kg over eight hours,

repeated two days later if there is an inadequate

response.

Aboubakr Elnashar

Page 21: Thrombocytopenia during pregnancy

Anti-D immunoglobulin

Indication:

non-splenectomised rhesus-positive women.

Mechanism:

creating a decoy to competitively inhibit the

destruction of antibody-coated platelets: raise platlet

count.

Doses: IV bolus

50 to 70 µg/kg.

Safe and effective in 2nd and 3rd T.

Monitor baby

neonatal jaundice

anaemia, and

direct antiglobulin test positivity after delivery. Aboubakr Elnashar

Page 22: Thrombocytopenia during pregnancy

Splenectomy

should be avoided in pregnancy if possible

May be necessary in extreme cases.

Performed in the second trimester and can at this

stage be performed laparoscopically.

Women with ITP who have previously been treated

with splenectomy should continue penicillin

prophylaxis throughout pregnancy.

Aboubakr Elnashar

Page 23: Thrombocytopenia during pregnancy

Other options for women who fail to respond to

oral prednisolone and IVIg

i.v. methylprednisolone

azathioprine or ciclosporin.

danazol and vincristine: Although not recommend

have been successfully used for severe resistant

cases in pregnancy.

Aboubakr Elnashar

Page 24: Thrombocytopenia during pregnancy

Platelet transfusions

last resort for bleeding or

prior to surgery

increase antibody titres

do not result in a sustained increase in platelet

counts.

Aboubakr Elnashar

Page 25: Thrombocytopenia during pregnancy

Fetal considerations

No place for serial fetal blood samples earlier in

gestation {Transfer of IgG increases at the end of

pregnancy and the baby is not at risk of bleeding

before labour and delivery}

The risk of fetal blood sampling via cordocentesis

(cord spasm, haemorrhage from the cord puncture

site) is similar (or even higher in thrombocytopenic

fetuses) to the risk of intracerebral haemorrhage

(ICH).

Aboubakr Elnashar

Page 26: Thrombocytopenia during pregnancy

CS:

only indicated for obstetric reasons.

{no conclusive evidence that SC reduces the

incidence of ICH, or that it is less traumatic for the

fetus than vaginal delivery}

Aboubakr Elnashar

Page 27: Thrombocytopenia during pregnancy

Neonatal consideration

Cord platelet count is determined immediately

after delivery

Neonatal platelet count:

only reaches a nadir after two to five days in affected

infants {splenic circulation is established}: most

hemorrhagic events in neonates occur 24-48h after

delivery at the nadir of the platelet count: monitoring

is necessary over this time.

IVIg

the recommended treatment for neonates with

bleeding or severe thrombocytopenia; this may be

given prophylactically if the platelet count of the cord

blood is low «20 x 109 /L). Aboubakr Elnashar

Page 28: Thrombocytopenia during pregnancy

Conclusion

ITP

The diagnosis of ITP is one of exclusion and

should only be made once other causes of

thrombocytopenia have been excluded.

Bleeding is unlikely if the platelet count is >50 x

109/L.

The risk of serious thrombocytopenia and

haemorrhage in the neonate from transplacental

passage of antiplatelet IgG is low.

CS is only required for obstetric indications and

epidural and spinal anaesthesiajanalgesia are safe

with stable counts >75 to 80 x 109/L.

Treatment, if required, should be with

corticosteroids or IVIg). Aboubakr Elnashar

Page 29: Thrombocytopenia during pregnancy

History and Physical

Normal

Repeat platlet count

normal

- Assume lab error

- No further workup

1st T platlet count low

Assume ITP

Counsel: risks of neonatal thrombocytopenia

Inform anesthesia and pediatric staff

Ensure no spontaneous bleeding

Ensure platelets >50K at delivery

1st T platlet count

normal

Assume gestational thrombocytopenia: no further work up

Abnormal

Aboubakr Elnashar

Page 30: Thrombocytopenia during pregnancy

Abnormal

History of medications

-Alternative medication

- Counsel maternal an fetal risk

Evidence of systemic disease

Management depend on type of illness e.g. self limiting viral illness or ch rheumatologic dis

Elevated BP with normal BP in 1st T

Assume hypertensive disorder of pregnancy

Management depend on gest age and s and s of maternal and f disease

Aboubakr Elnashar

Page 31: Thrombocytopenia during pregnancy

Thanks

Aboubakr Elnashar