Bone Marrow Failure, ASPHO Flashcards
give 5 causes of inherited bone marrow failure
Fanconi Anemia Schwachmond Diamond Dyskeratosis Congenita Diamond-Blackfan anemia Severe congenital neutropenia Thrombocytopenia Absent Radii Congenital Amegakaryocytic thrombocytopenia
Give 5 causes of acquired bone marrow failure = acquire AA
medications chemicals toxins viral infection PNH idiopathic/immune
Toxins, such as pesticides, arsenic and benzene
Radiation and chemotherapy used to treat cancer
Treatments for other autoimmune diseases, such as rheumatoid arthritis and lupus
Pregnancy - sometimes, this type of aplastic anemia improves on its own after the woman gives birth
Infectious diseases, such as hepatitis, Epstein-Barr virus, cytomegalovirus (si-to-MEG-ah-lo-VI-rus), parvovirus B19 and HIV.
Sometimes, cancer from another part of the body can spread to the bone marrow and cause aplastic anemia.
why is imp to distinguish type of IBMFS?
- conventional tx have lots of toxicityrequire diff txs
- donor selection for HSCT
- implciations for family planning
how does AA present? 4
- insidious; inciting event usually 6-8 weeks earlier
- often present with low plts and bleeding
- MCV HIGH
- fetal hgb often increased and “i” antigen often increased on RBCs
def’in of severe AA?
2/3 peripheral blood critiera:
ANC <500/ml
plts<20k/ml
retics< 1% corrected
1/2 BM criteria:
- <25% cellularity on bx
- cellularity 25-50% with <30% hematopoeitc cells
def’in of VERY severe AA?
ANC <200/ml
specific causes/questions to ask on hx when suspect acquired AA?
- radiation hx?
- cytotoxic agents, benzene, alcohol?
- idiosyncratic: chloramphenicol, anti-epileptic, anti-inflamm, and psychotropic meds
- viruses? EBV, CMV, sero-neg hep!!!, HHV6, HIV
- Autoimmuen diseae
- Immune disease like eosinophilic fasciits, hypogammaglobulinemia
- thymoma
- large granular lymphocytic leukemia
- PNH
- myelodysplasia
in hepatitis-associated AA< the hepatitis is _____ . cytoepnias occur when?
sero-negative; after hepatitis resolves
tx for hep-associated AA?
HSCT, immunosuppressive tx ( ATG, cyclosporine) just like for regular AA
work up for AA?
- BMA and bx
- cytogenetics on marrow; fish for MDS
- rule out IBMFS: chromosomal breakage assessment on peripheral blood with diepoxybutane or mitomycin C for FA; telomere length for DC
- PNH eval on flow of peripheral blood
- viral infection: serology of PCR for EBV, CMV, hep a/b/c, HIV, parvo
- eval of renal, hepatic, thyroid function
pathophys of idiopathic AA?
aberrant immune response to multiple stimuli: oligoclonal t-cell expansion with cytotoxic t-cells mediating stem cell destruction, suppression of normal marrow; also get overproduction of TNF-alpha and interferon-gamma
IST tx?
- Anti-human T cell serum: ATG (horse) or ALG (rabbit)…dosing >150 mg/kg or 40 mg/kg/day x 4 days
- steroids for 10-28 days to prevent serum sickness
- cyclosporine for 12 months; want stable counts for 3 months before tapering cyclosporine
is there a clear role for GCSF/GMCSF in AA?
no…can –> MDS/AML
how does cyclosporine work?
inhbiits prolif of t cells by binding cytosolic immunophili receptor– inhibit gene trx within t cell and also inhibitrs production of IL2 and interferon gamma
how does tacrolimus work?
blocks t-cell activation by calcineurin inhibition..2nd line agent in IST
ATG side effects?
- allergic: fever, rigors, urticaria, anaphylaxis – pre-tx with steroids, antihistamines, meperidine, slower rate of infusion
- serum sickness: fever, MP rash, myalgia, arthralgia, myocarditis, GI/CNS/renal sx…usual time frame: 5-10 days after ATG…tx with steroids
- immune-mediated cytopenias…lymphopenia: consider PCP ppx
Eltrombopag mech?
Thrombopoeitin receptor agonist…first line adn rescue therapy of SAA
goal plts in eltrombopag use?
50-200k
need to dose reduce eltrombopag in whom?
southeast asian population
AEs in eltromobpag?
hepatic decompensation (ALT, bili monitoring needed), skin rash, hyperpigmenation, cataracts, myelofibrosis
cocnern of eltrombopag?
more rapid progression from MDS to AML
what fraction of AAA respond to IST?
> 80%, with 10-30% needing ongoing CsA or relapsing
time frame to response in IST?
3-6 months
complete vs partial response in IST?
complete: noramlization of counts
partial: transfusion-indepentn