1. TROMBOCITOPENIAasociadoalEMBARAZO Pedro Garca Lzaro Hematlogo clnico HNAAA Chiclayo,10 de julio del 2007

2. TROMBOCITOPENIA Y EMBARAZO:EPIDEMIOLOGIA

Estudios prospectivos (nivell evidencia III): plaquetas 120,000-150,000/ul no son incomunes III-trimestre

Afecta al 7% de todos los embarazos

1357 embarazadas-parto a trmino:

• Promedio: 225,000/ul

• Intervalo confianza 95%:109,000-341,000

• Disminucin fisiolgica

3. DIAGNOSTICO DIFERENCIAL

Isolated thrombocytopenia

Gestational :74%

Immune (ITP) :4%

Drug-induced

Type IIb von Willebrand disease

Congenital

Thrombocytopenia associated with systemic disorders

Pregnancy-specific : 21%

Preeclampsia

HELLP (hemolysis, elevated liver function tests, low platelets syndrome)

Acute fatty liver

4. DIAGNOSTICO DIFERENCIAL

Not pregnancy specific :

Thrombotic microangiopathies:

Thromboticthrombocytopenicpurpura (PTT)

Hemolytic uremic syndrome (SUH)

Systemic lupus erythematosus (LES)

Antiphospholipid antibodies (SAF)

Disseminated intravascular coagulation (CID)

Viral infection (human immunodeficiency virus [HIV],Epstein-Barr

virus [EBV], cytomegalovirus [CMV])

Bone marrow dysfunction

Nutritional deficiency

Hypersplenism

5. GUIA PTI-2003

GUIDELINES FOR THE INVESTIGATION AND MANAGEMENT OF IDIOPATHIC

THROMBOCYTOPENIC PURPURA IN ADULTS, CHILDREN AND IN PREGNANCY

British Journal of Haematology, 2003, 120, 574596

6. NIVELES DE EVIDENCIA

IaEvidence obtained from meta-analysisofrandomizedcontrolledtrials

IbEvidence obtained from at least one randomizedcontrolledtrial

IIaEvidence obtained from at least one well-designedcontrolled study without randomization

IIbEvidence obtained from at least one other type ofwell- designed quasi-experimental study*

IIIEvidence obtained from well-designed non-experimentaldescriptive studies, such as comparative studies, correlatedstudies and case studies

IVEvidence obtained from expert committee reports oropinions and or clinical experience of respectedauthorities

7. GRADOS DE RECOMENDACIN

ARequires at least one r andomized controlled trialas part ofa body of literature of overall good quality andconsistencyaddressing specific recommendation

Evidence levels Ia, Ib

BRequires the availability ofwell-conducted clinical studiesbut norandomizedclinical trials on the topicofrecommendation

Evidence levels IIa, IIb, III

8.

C Requires evidence obtained from expert committeereportsor opinions and or clinicalexperiences ofrespectedauthorities. Indicates an absence of directlyapplicableclinical studies of good quality

Evidence level IV

9. LABORATORIO:PLAQUETAS75% todos los casos trombocitopenia embarazo

Patogenesis:Efectos de hemodilucin o depuracin acelerada de plaquetas x mecanismos inmunes o no inmunes.

CARACTERISTICAS:

trombocitopenia leve (raro < 80,000/ul)

Gestantes saludables con resto cuentas sanguneas normales

Ocurre comnmente en III trimestre

Plaquetas normales antes y despus del embarazo

No se asocia con hemorragia materna

11.

No se asocia con hemorragia fetal o neonatal

Trombocitopenia Gestacional es dficil distinguir de PTI:

• cuando trombocitopenia es identificada por primera vez durante embarazo

• cuentas previas de plaquetas:no estn documentadas, no historia previa de PTI

MANEJO

Cuidado obsttrico estandar

Parto con analgesia epidural si lo requiere

12. Prpura trombocitopnica inmune

Causa mas comn de trombocitopenia significativa en I trimestre

1 caso x 1000 embarazos

5% de casos de trombocitopenia-embarazo

PATOGENESIS:

• Anticuerpos contra glicoprotenas plaquetarias GPIIb/IIIa y GP Ib/IX

• Depuracin de estas plaquetas cubiertas por Ig-G x RES

13. PTI: DIAGNSTICO

Diagnstico por exclusin

Historia previa de trombocitopenia

Trombocitopenia moderada a severa: 20 x 109 l do not need treatment until delivery is imminent

Platelet counts >50 x 109 l are safe for normalvaginal delivery in patients with otherwise normalcoagulation

Platelet counts > 80 x 109 lare safe for caesareansection, spinal or epidural anaesthesia in patients withotherwise normal coagulation

16. Recommendation: (All Grade C)

In women who need treatment , both oral corticosteroids and IVIg appear to have a similar response rate to the use of these agents in the non-pregnant patient

Although many clinicians now favour the use of IVIg

in pregnancy there are no good comparative studies and the decision must take into account maternal clinical factors and preference in addition to the expense, availability and (remote) risks of microbialtransmission by IVIg.

17. Recommendation: (All Grade C)

There are no convincing data on the effect (beneficial or otherwise) of corticosteroids or IVIg on thefetal neonatal platelet count.

Severe refractory ITP may respond to high dose IV methyl prednisolone IVIg or azathioprine. If essential, splenectomy may be performed (ideally in the second trimester) and the laparoscopic route may have clinical advantages similar to those seen in non pregnant patients

18.

The mode of deliveryin women with ITP should be decided by primarily obstetric indications. There is no evidence to support the routine use of caesareansection (Grade B)

Women undergoing operative delivery should be considered for thromboprophylaxis according to their individual clinical risk factors. Standard prophylactic doses of UFH or LMW heparin should be used if thematernal platelet count is > 100 x 109 l (Grade C)

19.

Non-steroidal anti-inflammatory drugs should be avoidedfor post-partum or post-operative analgesia in women with platelet counts < 100 x109 l (Grade C)

The risk of clinically dangerous thrombocytopenia in the neonate is very low but cannot be predicted by clinical or laboratory parameters in the mother.

Attempts to measure the fetal platelet count by cordocentesis or fetal scalp blood sampling are not recommended as they carry more risks than potentialclinical benefits (Grade B)

20.

Because of the risk of haemorrhagic complications in the neonate the application of scalp electrodes for monitoring in labour and fetal blood sampling should be avoided. The use of vacuum extraction (ventouse) is contraindicated and complicated instrumental delivery (e.g. rotational forceps) should be avoided if possible(Grade C)

Cord platelet counts should be measured in all neonates of mothers with ITP and those with subnormal levels monitored clinically and with daily counts until after the nadir which usually occurs on d 25after delivery (Grade C)

21.

Treatment of the thrombocytopenic neonate should be reserved for those with clinical evidence of haemorrhageor a platelet count < 20 x109 l when there isusually a prompt response to IVIg (1 g kg).

Lifethreatening haemorrhage should be treated with immediate platelet transfusion and IVIg (Grade C).

22. CONCLUSIONES

PTI debe ser diferenciado de la trombocitopenia gestacional.

A pesar de que las plaquetas disminuyen en gestantes con PTI, una severa morbilidad y mortalidad es caractersticamente incomn para las madres

Frecuencia global de trombocitopenia en el infante es muy baja

• 6-10% infantes