Renal Transplant Flashcards
Indications for Renal Transplant
Contraindications to Renal Txp
Evaluation for transplant recipient workup, labs, imaging, additional tests?
HCG (F < 50 yo)
CBC
PT/PTT
UA
Urine protein/creatinine
CMV
EBV
Varicella Zoster
Hep b
Hep C
HIV
Syphilis
Quantiferon Gold Tb or PPD
ABO type and antibody type (prior to sx)
Baseline CT A/P or US (non-contrast outlines calcifications in vessels)
Cardiac screening (EKG)
Dobutamine Stress test when > 3 risk factors (>60 yo , smoking, HTN, HLD< DMII, prior CVD, > 1 year on dialysis, LVH)\
Malignancy evaluation (5 year wait for invasive/mets, 1 year localized/low grade)
GU evaluation prior to txp:
Evaluate voiding dysfunction: prostate scores, prostate US, UDS (not routine)
VUR → VCUG
CIC teaching
Asx urolithiasis generally not contraindication, may be risk for pyelo
Infective stones tx prior to txp
In renal txp with recurrent UTI or systemic symptoms, what is part of workup? DDx?
BK virus (can reduce immunosuppression), viruia, bacteria
anatomic assessment important
Uroflow/PVR
UDS
US or CT (obstruction, abscess, stones, cysts)
VCUG (if suspect VUR)
Risks of malignancy with immunosuppression?
Yes increased skin, lymphoma, kidney, bladder
ACKD → RCC (slight papillary predominance)
Why is kidney preservation necessary? How is it done?
Cold storage
Pulsatile preservation pump (reduce vascular spasm, extend preservation time, reduce need for HD of txp)
Renal tubular Na-K pump maintains high intracellular K dependent on ATP
Ischemia leads to depletion of ATP, loss of cellular K and Mg, increased Ca, anaerobic glycolysis and acidosis, activation of enzymes
Reperfusion, hypoxanthine (a product of ATP) → xanthine → free radicals and cell damage
What is ABO compatibility? Histocompatibility?
ABO blood groups are determined by cell surface carbohydrates on RBCs
Human major histocompatibility complex is a cluster of more than 200 genes on chromosome 6p21.31 responsible for HLA that are expressed as surface proteins on renal allograft
(most txp have some mismatch)
Discuss HLA classification:
HLA Class 1: expressed on nucleated cells HLA-A and HLA-B, class I antigens (as well as HLA-C) present endogenous antigens to cytotoxic T-cells
HLA Class II: expressed on cells of immune system
HLA-DR is class II antigen (aw well as HLA-DQ and HLA-DP)
Present antigen to helper T-cells
Live donor evaluations:
Healthy adults > 18 yo
no predisposing factors for CKD
w/o substance abuse or psych disorders
Normal surveillance screening (colonoscopy, PSA, mammogram, EKG)
Contrasted CT (size, shape, anatomic anomalies, number, length, location of arteries and veins)
Better kidney
Left with longer vein
Take kidney with fewer arteries
What can you get HLA antibodies from?
prior blood txf, transplants, pregnancy
Living donor operation key points:
low complication rate
hand-assisted Lap, full lap, robot (open rare)
ureter mobilized to point of crossing iliac
renal vessels ligated with stapler
extracted and placed in basin with iced saline
renal arteries cannulated
kidney flushed with ice-cold heparinized LR
Indications for pre-txp Nx? Timeframe?
chronic or recurrent acute bacteria pyelo
infected stones
heavy proteinuria
intractable HTN
PCKD with markedly enlarged kidneys
infected reflux
renal cystic dz with concern of malignancy
6 weeks prior to Txp
Significance of small bladder capacity in txp recipient?
Fibrosis or poor compliance may need pre-txp augment
small bladders may develop normal capacity and compliance post-txp unless fibrosis
Describe Hand-Assist Lap Donor Nx:
- NGT/Foley
- Lateral (donor side up)
- Camera trochar, additional under visualization
- Introduce hand port through lower midline
- Left Nx: mobilize descending colon, dissect ureter, open Gerota’s, dissect renal artery and vein, ligate adrenal vein and gonadal vein
- Right Nx: mobilize ascending colon, dissect ureter, open Gerota’s, dissect renal artery and vein
- Clip and cut ureter, staple artery and vein
- Remove kidney via hand port
- Flush with cold heparinized fluid
- Check for bleeding
- Close
How do you manage 2 renal arteries
side-to-side anastomosis (“pair of pants”)
on back table (txp surgeon)
For short allograft ureters, what are options:
Psoas hitch
Boari
Native UU
Native ureteropyelostomy
Pyelovesicostomy
Ileal ureter
Post op transplant recipient care:
UOP
change in GFR
Electrolytes
CBC
Foley 3 days or longer
Hydration
Advance diet in 1- days (extraperitoneal)
US (if suspicion of vascular compromise)
Immunosuppression 3 stages:
Work in synergy
Induction (lymphocyte depleting Ab or non-depleting Ab)
IV within 1 week of txp (Basiliximab)
Maintenance
3 categories (synergy) orally a few days after txp
Calcineurin-Inhibitor (tacrolimus, cyclosporin)
Antiproliferative agent (mycophenolic acid, azathioprine)
Co-stimulator blockade (Belatecept) MTOR (Sirolimus, Everolimus)
Corticosteroids (Prednisone)
Therapy for rejection
Rejection is lymphocyte mediated, can have Ab component
Corticosteroids
Lymphocyte depleting agents
If also Ab mediated (IVIG, Rituximab Bortezomib, Eculizumab, Plasmapheresis)
types of rejection for kidney txp:
- Hyperacute: immediately after revascularization due to pre-formed Ab → nx is required
- Acute rejection: weeks to months, before sxs, dec UOP and elevated Cr, confirm renal bx, cellular or Ab mediated (classification system)
- Chronic rejection (chronic allograph nephropathy): years, gradual decline in fx, bx → minimal mononuclear cell infiltration, fibrosis, vascular changes
Complications following Renal Txp:
Immediate vascular: impair perfusion to kidney or distal extremity
Restoration may require intimal flap repair, dissection, thrombectomy, bypass
Late RAS restored via angioplasty/stent
Fistula (calyceal-cutenous) or stricture
Necrosis of distal ureter at implantation site
Decline UOP, rising Cr, pain, swelling, leakage from incision
May require revision
Strictures (ischemia) → hydro, endourologic vs. redo anastomosis
Lymphocele (common)
Hydro, obstruction, iliac vein compression, DVT
IR drain, OR drain
AUR BPH (alpha blocker, 5ARI, sx - delay 1-2 mo)
Microhematuria
likely to be expected for 6 mo
after that time standard eval
Obstructing stones in allograft
PCN (with urosepsis or AKI)
4-5 mm conservative if GFR ok
Flexible URS superior to semi-rigid
1.5 cm PCNL (NO ESWL)
Medical Complications after Renal Txp:
Infections
Opportunistic
Viral → BK, CMV, EBC, HSV, Hep B/C
Bacterial → nocardia, listeria, Tb
Fungal → pneumocystis, aspergillus, cryptococcus
Parasitic → strongyloides, toxoplasma, leishmania, trypanosoma
Immunosuppression can be reduced if graft function stable
Life threatening infection → stop immunosuppression
COVID 19
UTI
Cancer
Skin cancer (SCC and basal cell, melanoma)
Lympoma/Leukemia
Kaposi’s sarcoma
Uterus/Cervix
Angogenital
Renal
Nephrotoxicity, HTN, DMII, Neurotoxicity
GI (diarrhea, n/v)
Bone marrow suppression
Osteoporosis
Cataracts
Immunosuppressant and side effects
25 yo F with IDDM s/p renal txp in right iliac fossa, on cyclosporine, mycophenolate, prednisone, with fever 1-2 and pain, 3 days after txp, decreased UOP, what labs? Imaging?
Labs:
UA, UCx
CBC
BMP
Cyclosporine
Imaging:
KUB (stent) Renal US (fluid, doppler)
Ddx of perinephric fluid collection and decreased UOP days after txp? Test? Tx?
Hemorrhage from arterial or venous anastomosis
Urinoma
Lymphocele
Put IR drain, send fluid
Cr
Culture/Stain
KOH (fungus)
CT cystogram or Contrast CT
Antegrade imaging via PCN (if not apparent)
Tx:
small leaks → foley +/- PCN or stent
persistent or large → anastomotic revision
type of of ureteral anastomotic revision for txp kidney if necrosis, leakage?
Reimplantation
Ureteropyelostomy to native ureter, nx of native kidney (planned)
Ureteroureterostomy to native ureter
Boari flap
Vesicopyelostomy (anastomosis with renal pelvis of txp)
Veiscocalycostomy
Ileal Ureter
