At which platelet counts is spontaneous bleeding, clinically significant bleeding, and life threatening hemorrhage possible?
- Spontaneous = <50 x 103/uL
- Clinically significant = <20 x 103/uL***
- Life threatening = <10 x 103/uL
What are the 4 most common conditions associated with fetal/neonatal thrombocytopenia?
- Alloimmune thrombocytopenia
- Congenital infection (i.e., CMV, toxoplasma, rubella, HIV)
- Aneuploidy (i.e., triomy 18, 13, or 21 or triploidy)
- Autoimmune conditions (i.e., ITP, SLE)
Kasabach-Merrit syndrome can be associated with early-onset neonatal (<72 hrs) thrombocytopenia and what other finding?
Late onset neonatal (>72 hr) thrombocytopenia is almost always due to what?
Which disorder in children causing thrombocytopenia is a primary platelet consumption syndrome?
Idiopathic thrombocytopenia purpura
Which 2 disorders causing thrombocytopenia in children are due to combined platelet and fbrinogen consumption syndromes?
- Kasabach-Merritt syndrome
Ecchymosis/bruising may be seen with platelet disorders in childre, you should worry if what 3 things are seen?
- Atypical distribution
- Bruising inconsistent with activity or force of injury
A young male presenting with eczema, recurrent infections, and small platelets should make you think what?
How does acute idiopathic thrombocytopenic purpura (ITP) most commonly manifest in a child and what is the platelet level/morphology?
- Sudden onset of petechiae and bruising in otherwise well child; most often following a viral infection
- Platelet count usually <20x103/uL ---> platelets presents are usually large
Which 3 treatments are most commonly used for acute ITP (usually only when severe or life-threatening hemorrhage)?
- Prednisone (or other corticosteroid)
- Anti-D immunoglobulin (only in Rh (-) children)
After 12 months of ongoing ITP (chronic) in a child what other disorders should you evaluate for?
- Autoimmune diseases like SLE, chronic infections like HIV
- Non-immune causes like platelet type vWF, x-linked thrombocytopenia
- H. pylori infection***
Hemolytic-uremic syndrome (HUS) is due to what?
Vascular injury (especially kidneys and colonic mucosa) from toxins from E.coli O157:H7 causing consumption of platelets
What is the only cell line involved in ITP?