Recent progress in im/m therapy and the post-Tx management have led to improving both graft and recipient survivalin pediatric kidney transplantation.
COMPLICATIONS OF PEDIATRIC RENAL TRANSPLANTATION
Abbreviations:
o
Ac Rj: acute rejection
o
ACR: Acute
cellular rejection
o
AKI: acute kidney injury
o
AMR: acute antibody-mediated
o
CNI: Calcineurin inhibitor
o
CIN: Calcineurin inhibitor nephrotoxicity
o
CAI: Chronic allograft injury
o
Csp: Cyclosporine.
o
CVS: cardiovascular disease.
o
DM: diabetes mellitus
o
DGF: delayed
graft function
o
FSGS: focal segmental glomerulosclerosis.
o
aHUS: atypical hemolytic uremic syndrome
o
HT: hypertension,
o
im/m: immunosuppressive.
o
KTx: Kidney transplantation.
o
MPGN: membranoproliferative glomerulonephritis.
o
SCr: serum creatinine
o
Tac: Tacrolimus
o
TR: transplant recipients.
o
Tx: transplantation
o
PNp: pyelonephritis
Recent progress
in im/m therapy and the post-Tx
management have led to improving both graft and ptn survival in pediatric KTx TR. However, long-term benefits have been limited by the sequelae related
to im/m, rejection, and recurrence of the original kidney disease. Several complications of KTx appear as graft dysfunction. Etiology of kidney graft dysfunction will
be varied with the timing after Tx.
The timing periods can be categorized as:
o
immediate (0-one week post-operative),
o
Early (1-12 weeks
post-operative),
o
Late acute (after 3 mo), & late
chronic (years).
● Etiology of DGF (immediate renal failure that persists after Tx) include:
o
Post-ischemic AKI,
thrombosed renal artery/vein,
o
Urologic sequelae (i.e., urine
leak or obstructive uropathy) &
o
Hyperacute Rj,
rare.
● Ptns with initial graft function who develop early kidney
insufficiency (i.e., 1-12
weeks post-Tx), the major causes of
graft dysfunction include:
o
Ac graft Rj,
o
Ac Rj toxicity,
o
Obstructive uropathy
o
Infectious episodes,
o
Fluid deprivation and hypovolemia, &
o
Recurrence of the native disease.
● Kidney allograft dysfunction acutely observed > 3 mo after Tx
is mostly due to:
o
Ac allograft Rj,
o
CNI toxicity,
o
Obstructive uropathy
o
Hypovolemic states, PNp,
&
o
Recurrence/de novo native renal disease.
● Slowly progressing renal diseases that observed over years post- KTx most commonly induced by:
o
Viral infection,
o
Chronic allograft injury,
o
CNI nephrotoxicity,
o
HT nephrosclerotic
kidney disease, &
o
Recurrent or de novo renal disease.
● Etiology of DGF that seen after KTx may include:
o
Hyperacute Rj.
o
Post-ischemic AKI,
o
Renal artery/vein thrombosis,
o
Urinary leakage or obstructive uropathy,
o
Etiology of graft dysfunction from 1 to 12 weeks post- KTx include:
1. CIN,
2. Ac Rj,
3. Obstructive
uropathy
4. Infectious
episodes,
5. Hypovolemic
states, &
6. Recurrence
of the original disease.
o
Causes of graft dysfunction that develop
acutely > 3 mo after Tx include:
1. Ac Rj,
2. CIN,
3. urinary
obstruction,
4. hypovolemia,
&
5. Recurrent
and de novo kidney disease.
o
Causes of allograft dysfunction that slowly
developed over years include:
1. CAI
2. CIN,
3. HT nephrosclerotic kidney disease,
4. Viral
infection, &
5. Recurrent
or de novo renal disease.
● Ac Rj can be expected with an acute rise in the SCr level and can be confirmed histologically via allograft biopsy with the finding of AMR & ACR. So, SCr should be regularly monitored for the early diagnosis of Ac Rj.
● Despite that CAI (chronic
allograft injury) is the most commonly observed
etiology of graft loss after the 1st y after Tx, its underlying background still uncertain. The diagnosis can be
expected via:
o
Slowly elevated SCr,
o
Rising proteinuria, &
o
Worsened HT.
● CNI (Csp & Tac)
nephrotoxicity can be seen acutely that is highly
reversible after dose modification,
or may be progressing to CKD that is usually
irreversible.
● In pediatrics KTx,
recurrent native kidney diseases inducing allograft loss can be observed
in 5-15 % of ptns.
Primary pediatric native kidney disease with a high
rate of recurrence rate in the kidney allograft may include:
o
FSGS,
o
MPGN,
o
Primary hyperoxaluria
o
Genetic types of aHUS.
●Other
complications that can be observed with pediatric kidney TR may include
HT, CVS disease, infection, cancer, DM, anemia, and surgical sequelae (e.g.,
urological and vascular sequelae). These can be contributing to allograft injury/dysfunction.
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