Lecture name:-Renal failure and Renal transplantation.
By Dr.Salam Abd ELameer Yihya. (F.I.B.M.S.URO)
Time:-1 hr.
Aims of the lecture:At the end of the lecture , the student should be able to :
1- diagnose and differentiate acute and chronic renal failure.
2-Recognize which patients are suitable for renal transplantation and
those who are not.
3-Identify the main steps in choosing and preparing the donor and the
recipient.
4-Identify the main complications of renal transplant and how to
manage these complications.
Contents:
*Acute and chronic renal failure:
*Indications and contraindications of renal transplant:
*Steps of renal transplant:
*Complications:
Renal failure:
A) Acute R.F.: it ccc. by sudden and usually reversible decline in the
renal function.
Causes:
:1) Prerenal causes of acute renal failure include
.hypovolaemia •
.blood loss •
.sepsis •
.cardiogenic shock •
.anaesthesia •
.hypoxia •
2) Renal causes: which either renal parenchymal dis or renal vascular
diseases as:
a. Glomerulonephritis
b. Interstitial nephritis
c. Toxin, drug or dye-induced
d. Hemolytic uremic syndrome
e. Acute tubular necrosis
g. thromboembolism of micro vasculature of the kidneys.
C) Postrenal
.Calculus in patients with solitary kidney .
.Bilateral ureteral obstruction .
.Outlet obstruction .
Dx. and treatment:
By history and examination conc. On the fallowings:
*symptoms include: oliguria or anuria ,nausea, vomiting ,generalize
malaise or s.t. deterioration in the level of consciousness.
*signs as: differ according to the cause as dehydration and
hypotension(prerenal), fever and loin pain(renal and post renal)
*Ix. Include: renal function tests, urinalysis, hematological tests,
ultrasonography.
Patients with renal failure have elevated blood urea (n=3.5-7.5 mmol/l)
and serum creatinine(n=64-124 mmol/l).
*Treatment:
A)The cornerstone in the treatment is to treat underlying cause as
.correction of hypovolemia , blood loss or hypotension.
.withdrawal nephrotoxic drugs or toxins.
.By pass obstruction by Foley catheter ,double-J stent or nephrostomy.
B) I.V. fluid and diuretics(frusamide).
c) s.t. few cessions of hemodialysis in critically ill patients.
B)Chronic R.F.(End stage R.F.)
It ccc. By gradual decline in the renal function .
It differ from acute R.F. by the followings:
1.Irreversible.
2.Usually ass. With anemia.
3. Renal parenchyma either thin or loss of cortico medullary ddx.
Etiology:
1. D.M.
2. Hypertension. 3. Renal vascular diseases.
4. Chronic pyelonephritis.
5. Glomerulonephritis.
6. some cases of acute R.F. can progress into chronic form.
Clinical features:
.Patient with chronic R.F. may be asymptomatic (azotemia).
.Non specific signs and symptoms as nausea,vomiting,generalize
maliaze, lassitude , anemia and /or hypertension.
. In late cases,peripheral neuropathy and/or renal osteodystrophy.
Tretment:
A) General measures: as control of hypertension , decrease salt and
protein in the diet , treatment of anemia and hypocalcemia.
B) Definitive treatment: by renal replacement therapy. which include:
1-Dialysis: peritoneal or haemodialysis.
2-Renal transplant.
Most patients with end-staged renal diseases (ESRD) are suitable for
renal transplantation.
RENAL TRANSPLANTATIOIN:
*Indications and contraindications:
It is indicated in patients with ESRD which may occur as a result of:
1. Chronic pyelonephritis.
2. Chronic glomerulonephritis.
3. Congenital renal diseases as polycystic diseases.
4. Others: as gauty nephritis, diabetic nephropathy.
Absolute contraindications for renal transplant are:
1- Active infection.
2-Sever vasculopathy.
3- Cancer any where in the body.
4- Metabolic disease likely to recur (cystinosis).
Steps of renal transplant:1) Selection of donor:
A- Living donors:
1. Living related kidney donors:
An identical twins or immediate relative (brother, sister, father,
mother, son or daughter) can be a donor kidney.
2. Living unrelated donors:
Include any person who is competent, willing to donate and found to
be medically and psychosocially suitable may be a living kidney donor.
B- Cadaveric (Deceased) donors:
Most kidneys used for transplantation comes from peoples have
been diagnosed as brain death.
The standard criteria for deceased donors are: brain death from 5-60
yr. person with normal renal functions with no history of systemic or
infectious diseases.
2) Compatibility:The principle histocompatibility antigens in human are :
Major Histocompatibility Complex (MHC) and ABO blood group
system.
*ABO blood group system: Any pt. who is able to give blood to a
recipient, he may be able to give a kidney to that recipient.
*MHC:
.MHC describes a region of genes located on chm. 6 which encodes
proteins responsible for rejection of tissues.
.In human, the cell surface markers of MHC are called Human
Leukocyte Antigens (HLA) which detected on the surface of all
nucleated cells.
.There are 6 HLA antigens constitute the individual tissue type.
.A cross-match against both donor T and B lymphocytes is performed
and transplant is not done if anti-HLA antibodies are present.
.Mixed Leukocyte (Lymphocyte) Culture (MLC) measure the direct cell
to cell reactions of lymphocytes from the donor and recipient.
MLC takes 5 days (while HLA tissue typing takes 12 hr.) so not used in
emergency situations in cadaveric kidneys.
Pretransplant blood transfusion generally should be avoided and
anemia of renal failure should be treated with recombinant
erythropoietin.
3) Donor nephrectomy for transplantation:
.The living donor nephrectomy is performed in an operating theater
adjacent to the transplant surgeon theater who prepared the recipient
to receive the kidney.
.The donor is all ways left with the better kidney.
.If the tow kidneys are of equal function, the left kidney is preferred for
transplant?
4) Extra corporeal renal preservation:
a- Simple hypothermic storage and flush solution:
Once removed, kidneys are flushed and stored in hyperosmolar
,hyperkalemic , hyponatraemic solution at (4-10 C).
This is sufficient for 24 hr. of preservation.
b- Pulsatile perfusion:
Alternative method for preservation which have many advantages but
it is costly and require a technologist.
5) The Recipient operation:
*Generally preoperative recipient blood transfusion should be
avoided?,and anaemia of CRF. Is effectively treated with recombinant
erythropoietin.
*Preoperative nephrectomy of the recipient indicated in:
a- PCKD.: when reach big size that make no place for the transplanted
kidney.
b- Resistant hypertension due to renin secretion.
c- Recurrent infections.
d- tumor of the recipient kidney
6)The standard renal transplant surgery:
.Either iliac fossa are suitable for the transplant but the right iliac fossa
is preferred .Why?
.The renal vein is usually anastomose to the external iliac vein first.
.The renal artery is usually anastomose to the internal iliac artery.
.The ureter is usually implanted to the bladder .
Immediate post operative care :
1.Immediatly after transplant, it is advisable to obtain baseline duplex
Doppler ultrasound to confirm patency of the renal vessels .
2. Monitor urine out put and c.v.p. (urine out put of 1cc/kg/hr.) is
desirable.
3- I.V.fluid replacement at cc/cc of urine is usually sufficient.
4- Immune suppression therapy:
.Few days before and then after operation we give
immunosuppressant drugs to reduce as much as possible the rejection
Theses drugs are:
a- Azathioprine (Imuran): 6-mercaptopurine derivatives.
b- Cyclosporine: It is a potent metabolite of a soil fungus. Serum
level should be monitored because it is nephrotoxic.
c- Mycophenolate Mofitel: Now it replace azathioprine as
antimetabolite with less immune suppression.
d- Steroids : prevent and treat renal transplant rejection.
e- Antilymphocytic drugs: as tacrolimus.
Complications:
1) Renal graft rejection : 3 types of rejections can occur these are:
1. Hyper acute rejection: Occur immediately after revascularization of
the kidney when preformed anti-HLA anti bodies are present.
It leads to graft thrombosis and the transplanted kidney should be
removed.
2. Acute rejection: It can occur at any time after transplantation
(mostly with in the first 3 monthes) and ccc. By fever, chills,
hypertension, diminish urine out put, swelling and pain of the graft.
Most episodes of acute rejection are reversible.
3. Chronic rejection: Process of gradual progressive decline in renal
function over time.
Treatment is often in effective and another transplant may be needed.
2) Surgical technical cx.: as
1. Vascular : as haemorrhage or stenosis or thrombosis of the vessels.
2. Urinary leakage:
3. Urinary tract obstruction:
3) Medical complications: as
1. Urinary tract infections: (bacterial, viral or fungal).
2. Post transplant D.M.:
3. Post transplant cancer .
Introduction:-