13. Table 3: Comparison of natural history of early
and late onset thrombocytopenia in neonates
EARLY LATE
.
Mild to moderate . Severe
(platelet nadir rarely <50 × 109/l) . (platelet nadir frequently <50 × 109/l)
Evolves slowly over several Rapid onset and progression over 24–48
hours. hours
.
Associated with: Associated with: Sepsis and NEC
pregnancies (PET, IUGR, maternal Dm)
Mechanism: Mechanism:
Impaired platelet production Combined platelet consumption and
impaired production
Rarely requires specific treatment Multiple platelet transfusions often
required.
14. Thrombocytopenia: assesment
Term or preterm?
Other medical conditions
Are there features suggestive of
congenital infection?
Congenital anomalies/dysmorphism
15. Pathogenesis
Pre-eclampsia (Early onset)
Thrombopenia with neutropenia
Nadir at 3-4 days of life, recovering to normal levels by
day 7-10
Disruption of hematopoietic progenitor cell
commitment to megakaryopoiesis
Prematurity may exacerbates.
19. Neonatal alloimmune
thrombocytopenia (NAIT)
Feto-maternal Alloimmune thrombocytopenia (FMAIT)
A mother lacks a platelet antigen that her fetus
inherited from father.
Maternal IgG vs “foreign” antigen on fetal platelets
cross the placenta and destroy them
Most common platelet antigen HPA-1a and HPA-5b
20. Maternal autoimmune
Thrombocytopenia
Ex. ITP, SLE
Maternal antibodies vs. platelet antigens
a) Glycoprotein IIb/IIIa and Ib/IX
b) Antibodies cross placenta and bind to
these antigens on fetal platelets.
32. References
NeoReviews.org: Approach to the Newborn who
has thrombocytopenia. Vol.5 No.10 October 2004
Curr opinion Obst Gynecol: Platelet disorders in
pregnancy. 2001;13:115-119
CurrOpinPediatr.2001 Feb;13(1):16-21
CurrHematol Rep. 2006 Mar;5(1):55-63
Early Hum Dev.2005 Jan;81(1):35-41
Avery’s Diseases of the Newborn. Taesch et
Ballard.
Editor's Notes
Cm’nest hematolo.abnormay.pediatricians n in labs
Severe –concern,treatment,Intracranial bleed mostly in NICU neonates
Severe thrombopenia in term infants rare3/1000 term infants.1.deg.of thro.penia inversly prop.to gestational age. 2.Severe thrombopenia,risk of bleed
Majority episodes present within 72 hrs . PET Pre-eclampsia , maternal diabetes with vasculopathy
direct cytotoxicity of on hematopoietic cells, immune-mediated destruction of infected cells, or impaired bone marrow stromal function by . nonspecific autoantibodies that cause antibody-mediated platelet destruction…coagulopathy,hemangiomas n thrombocytopenia