ASN QBank Pearls - Renal Transplant Flashcards
(294 cards)
imunologia do tx
Major histocompatibility complex (MHC) is a family of genes that encodes HLA.
HLAs: Glycoprotein encoded by genes on chromosome 6. Unique like fingerprints. Immuno-dominant antigen for both humoral and cellular alloreactivity.
MHC I -> HLA Class I: HLA-A, HLA-B, HLA-C On all nucleated cells (also platelets). Not on RBCs
MHC II -> HLA Class II: HLA-DRB1, DRB3,4,5, HLA-DPB1, DPA and HLA-DQB1, DQA on B and certain T lymphocytes and Myeloid cells (antigen presenting cells (APC), Macrophages, Dendritic cells, activated human endothelial cells, BLy).
Epitopes: Hypervariable regions in the HLA distal domains and are recognized as foreign.
Non HLA: Eg: Angiotensin type 1 receptors, endothelial cells, Agrin, glutathione-S-transferase T1, GBM, Protein kinase, CXCL9,11, IFN-g, glial cell-derived neutrophic factor. Have a role in AMR, detected by cell-based assays of endothelial cells (IF and Flow cytometry)
ABO Ags: on ALL cells.
Barrier to transplantation exception: -A2 (donors) - low A Ags & develop tolerance. -Rh present only on RBCs.
sensitization of immune system occurs from
- blood transfusions
- pregnancy
- prior transplants
panel reactive antibodies (PRA)
- tells how sensitized a patient is to HLAs in general population
- 0-100%
donor specific antibodies (DSA)
- tests presence of Abs to DONOR’S HLA types only
- semiquantitative
crossmatch
- combines donor cells w/ recipient serum
crossmatch prediz oq? rejeicao hiperaguda
o crossmatch entre doador e receptor tem q ser negativo
rejeicao hiperaguda
Antibodies
Ab to the HLA molecules on the donor kidney
blood groups between donor and recipient must be
compatible (like blood transfusion)

HLA matching has better outcomes if
match is 6/6
MHC mismatch is a risk for allograft (donor organ) rejection because peptide-binding regions of the MHCs are highly immunogenic.
Most immunogenic MHCs are A, B, and DR which are used as donor-recipient matching criteria for kidney transplantation.
HLA typing of donor and recipient determines
- matching compatibility
- range from 0/6 to 6/6
can rejection still occur if HLA match is 6/6? and, if yes, why?
- yes!
- non-HLA incompatibilities
contraindications to kidney transplantation
- poor cardiac function
- morbid obesity
- psychosocial issues which can affect compliance
- active infection
- recent, unresolved cancer
- ANY serious comorbidity which reduces life expectancy
Active infections
Active malignancy
Active psychiatric illness
Unacceptably high perioperative risk (unrevascularizable CAD)
High burden of comorbid conditions (dementia, end stage lung/heart disease)
infections that need to be tested for in a transplant recipient
- HBV
- HCV
- EBV
- CMV
- syphilis
- HIV
- latent TB
contraindications to living donation
absolutas
- age < 18
- GFR < 80 ml/min
- hematuria/- proteinuria RELATIVA
- HTN com lesao de orgao alvo
- DM
- obesity imc>35
- neoplasia ativa
- infectious disease ativa
- significant, unresolved medical issues
- psychosocial factors
- inability to give informed consent
-nefrolitiase com possibilidade de recorrencia-citinuria, hiperoxaluria primaria , struvita
donor evaluation
- H&P
- CMP
- FLP
- GFR; 24 hour urine
- UA, C+S
- serum hCG
- EKG
- CXR
- TTE
- age-appropriate cancer screening
- CT a/p
- SW evaluation
what cancer screening needs to done for transplant recipients?
- mammogram
- PAP smear
- PSA
- colonoscopy
waiting time after cancer treatment for most cancers before proceeding w/ transplant?
2 years
waiting time after cancer treatment for metastatic breast, colorectal, and melanoma before proceeding w/ transplant?5 years
waiting time after cancer treatment for non-melanoma skin cancer and some in situ malignancies before proceeding w/ transplant?
none, considered low risk
long term risk of ESRD over 15 years for kidney donor
6 fold increase
doadores tem maior risco de HAS, proteinuria, e falencia renal
risco de eskd = 1% apos 15 anos
se um doador precisar ir pra fila é prioridade
funcao renal reduz 30% apos doacao
minimum criteria for listing for kidney transplant
- initiation of dialysis
- GFR < 20 ml/min (time starts at time of eval and consent given to list)
what is a nonstand kidney?
- higher kidney donor profile index (KDPI) score (higher = worse)
- cardiac death donor (longer CIT)
- “higher-risk” donors
- HBV and/or HCV donors
thymoglobulin MOA
depletes T cells
preparacao com anticorpos policlonais com grande numero de especificidade antigenica que incuem antigeno de superficie de linfocitos t e b, cels nk , plasmocitos e moleculas relacionadas a adesao celular
thymoglobulin adverse effects
- leukopenia
- thrombocytopenia
- fever
- flu-like symptoms
basiliximab MOA
blocks IL-2 receptors in T cells
CNI MOA
binds FK-binding protein thus inhibiting response to IL-2
CNI adverse effects
- Afferent arteriole vasoconstriction
- hyperkalemia
- metabolic acidosis
- hypomagnesemia
- hyperglycemia and HLD by blocking beta cells in pancreas
- renal fibrosis (long-term)
azathioprine and MMF adverse effects
- leukopenia
- MMF can cause diarrhea
obs os niveis de aza e micofenolato nao se correlacionam bem com a toxicidade
use of azathioprine and allopurinol is
contraindicated
A combinação de azatioprina e alopurinol aumenta o risco de um indivíduo desenvolver mielotoxicidade grave. Se houver necessidade da prescrição do alopurinol, a dose da azatioprina deverá ser reduzida em dois terços. [carece de fontes] Além disso, contagens hematológicas deverão ser realizadas com freqüência.
sirolimus MOA
mTOR inhibitor; blocks FK-binding protein thus inhibiting IL-2 response
adverse effect of sirolimus
- poor wound healing
- proteinuria
belatacept MOA
blocks accessory pathway of T cell stimulation
advantage of using belatacept avoid CNI nephrotoxicity






















