Q.670. How could patient survival after renal transplantation be affected?
Solid-organ transplant (SOT) TR are immunocompromised and may be at higher risk for severe COVID-19 disease as compared to general population. Two large observational studies of SOT recipients with COVID-19, about 80-90 % of ptns required hospitalization; of those, nearly 40 % required intensive care & 30 % required mechanical ventilation. At one month, mortality (MR) exceeds > 20 %. These findings suggest: TR are at a higher risk for poor outcomes, multivariate analyses in both studies reported that age & chronic co-morbidities were the primary drivers of MR rather than immunosuppression.
KIDNEY TRANSPLANT
I.
General topics.
II.
Infection.
III.
Drugs of transplantation.
IV.
Rejection after transplantation.
V.
Complications of transplantation.
VI.
Recrrence.
VII.
Xenotransplantation.
VIII.
Stem cell transplantation.
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﴾﴾ I. General Topics. ﴿﴿
Q.670. How could patient survival
after renal transplantation be affected?
A. Kidney
Tx.
is ➳ ttt of choice for selected ptn é ESRD. It confers the highest survival benefit
among all different RRT. Survival
benefit hs bn obs. in: [diabetics, African-Americans, obese ptn.s & in ptn
in all age groups, as well as in those who’re recip. of marginal
kidneys] . Reasons are unclear. Despite survival benefit
conferred by Tx. comp. to DX., R. recip. still have a high M.R. comp. é controls. Survival
rates vary based é
source of allograft, age &
pres. &
degree of severity of comorbid dis.. Other factors:[Gender, race
& degree of im/m.].
C.V.S. dis. leading
cause of death for adult R. allograft recip.. De novo H.F.
is common after R.Tx. & associated é poor
survival. Among ptn. requiring intervention for CAD after
Tx.,“myocardial
revascularization” is associated é
acceptable immediate & long-term survival & similar outcomes in percutaneous & surgical techniques. Survival
of diabetics after R.Tx. is lower thn tht for nondiabetics due to
pres. of PVD.. However,
survival é Tx. diabetics is still markedly better thn tht é DX. .
Infections🠞leading cause of mortality é early post Tx. period
& are related to the level of overall im/m. rather thn
the use of a sp. im/m. agent. Particular causes of death hs changed over time
& varies é age. Single center
study: % of deaths due to: cardiac dis., cancer & stroke appear to hv increased.
Q.671. How could a living unrelated donor share in R.Tx.?
A. Trials
to increase No. of available kidney allografts including the use of living kidney
donors. This including: kidney donation by biologically unrelated persons.
Ethical considerations é
living unrelated organ donation in U.S. are somewhat similar to those
involved in living related organ donation. So far, living unrelated kidney
donation has been based upon altruistic ideals and has not been driven by economic
incentives. Basic medical evaluation🠞same as living
related donors. A major concern é living
donors 🠞long-term impact of having a solitary
kidney.
Outcomes fr. HLA-mismatched
pairing are similar to haploidentical
relatives. One-y. values are comparable to living-related
donors & better than é deceased
donor kid.. Multiple efforts to expand living unrelated donor
pool, e.g. paired-kidney-exchange
program & non-directed live-kidney donor (altruistic donors or "good samaritan"
donors) 🠞to
donate a kidney, but do not identify sp. recipient. Incr. living
donation rates, related/unrelated, needs to improve
ptn. education.
Q.672. How could you evaluate a living kidney donor?
A.Thorough
medical, surgical & psychosocial evaluation of prospective donor is
performed. In U.S.,“Independent Living Donor Advocate” is mandated: a separate person é clear understanding of
Tx. to promote the best interest of the potential donor, advocate for his
rights & assist the donor to obtain &
understanding information regarding: [consent
& evaluation, surgical procedure]. “Purpose of evaluation”🠞ensure
donor is in good health, has normal kid. function,
structure & not a risk to dis. transmission. So, large No. of
clinical tests us. performed for donor evaluation. Donor may be accepted,
excluded, or require more assessment. There’re a signif. No. of generally
accepted absolute C.I.. There’s also inter-center variability in relative exclusion criteria
for donation. Decision-making is a nuanced one & incorporates donor
autonomy (D.A.), which’s determined by donor’s risk understanding,
relationship to recip. & benefit of donation.
Since black & Hispanic donors are more likely
to develop CKD, H.T.& D.M. after donation comp.to white donors, African-American & Hispanics should be
counseled regarding these findings by living donor advocate. Also, African-American
or Hispanic ethnicity, we recommend utilizing the most
conservative assessment of GFR, 24-h. ambulatory B.P.
monitoring & glucose tolerance
testing. Women of child -bearing age underwent nephrectomy adverse effect
upon future pregnancies: [fetal
loss, gestational D.M., gestational H.T. & pre-eclampsia] é pregnancy after kid. donation. So,
it’s recommended: women should have completed planned child-bearing prior to donation. Nevertheless,
the generally good outcomes should not exclude donors who have not
completed child-bearing.
Q.673. What are the absolute contraindications for kidney donation " What are the“relative contraindications”?
A. Absolute contraindications
including:
1) Proteinuria and/or
hematuria.
2) Impaired renal function (defined
as
GFR <80 mL/min/1.73
m2).
3) Markedly abn. urologic & renal vascular abn.
4) Active infection.
5) Ch. active viral infec. (HIV, HTLV, Hepatitis B & C virus)
6) Active malignancy.
7) Hist. of malignancy: lung, breast, R., urologic, G.I., melanoma, etc.
8) Ch. illness: Pulm., liver, autoimmune, neurologic,
or cardiac dis.
9) Clinically significant H.T..
10)
D.M.
11)
Nephrocalcinosis, bilateral kid. stones, or
recurrent nephrolithiasis
12)
Poorly controlled psychosis.
13)
Active substance abuse.
14)
Pregnancy.
15)
Diso. requiring anticoagulation .
- Relative
C.I. to kid. donation, incl. the foll.:
1) Active peptic ulcer dis..
2) History
of nephrolithiasis
3) Urological abnormals (eg, multiple renal vessels)
4) Morbid obesity, most commonly defined as
B.M.I.>35 y.
5) Age
>65 or
<18 y.s
6) Strong
F.H. of D.M. or H.T.
7) F.H.
of renal cell cancer.
8) ABO or HLA incompatibility, wch may
allow for Dsz.
Exclusion criteria: older age; borderline/mild H.T., borderline/ low
GFRØ variable. Risk of D.M.: F.H. of D.M.,
gestational D.M., FBS strictly observed. Exclusion
criteria based upon FBS or OGTT. varies by Tx. center.
Obtaining H.B. A1C or a formal OGTT
may also be used to assess presenseor risk for D.M. . " Age: Previously, older
donors, (50 y), were not
considered suitable. However, kidn. fr. such donors are now commonly used
if these individuals are in good physiccal & mental condition
& hv adequate kid. function. In
U.S. almost 60 %
of centers hd No upper age limit for kid.
donors. As regard lower age limit, most centers report: an age < 18 y. is an absolute
exclusion criterion. " Renal function: Most
centers recomm. GFR of at least 80 mL/min. If
R. function Eval-uated via a cr.cl., adequacy of 24 h. urine collection shd be carefully
assessed. Furthermore, dietary intake of protein should be at least 1 g of protein/kg/B.W.,
since a low protein diet may Cr.Cl.
by as much as 10
mL/min.
Difficulties to get accur-ate Cr.Cl., incl. variability in urine collections spurious results.
Some centers use estimated GFR e.g.
MDRD equation for
initial screen. Donors é
GFR< 80 mL/min by initiallyisotopic scan.
DRD-epi🠞GFR more accurately thn MDRD equation
among those é true GFR > 60 mL/min. How ever, equations are
frequently inaccurate. Ideally, protein excretion should be on ¸ 24 h. collection. Some
centers use spot ur. protein/cr. ratio or microalbumin/Cr. ratio.
Most centers exclude ptn é 300 mg/d.,
while
others hv lower threshold of >150 mg/d.
Definition of hematuria vary
é each center. In U.S., some centers
define hematuria as at least 10 RBC/hpf, while others: 3 RBC/hpf. Others
only accept donor é
hematuria if urologic evaluation & R. biopsy are -ve. H.T.: Alth. florid
H.T. is clearly a C.I. for donation, precise risk to donors é border-line H.T. & those é F.H. of H.T. is less clear. Larger Tx.
centers tend to use such donors é
greater frequency thn those é
smaller programs. History
of nephrolithiasis: In U.S., majority of Tx. centers
accept a donor é P.H.
of nephrolithiasis if evaluation reveals abs. of stones & Normal
metabolic studies.
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