CRF pdf - D. Dhyiaa - Muhadharaty

Fifth Stage

Internal Medicine

Dr. Dhyiaa – Lecture 6

Cronic Renal Failure

It is a progressive ,irreversible loss of renal function developed over a period of

years manifested initially as only biochemical abnormalities

((AZOTEMIA))

and

eventually development of the clinical signs and symptoms of chronic renal

failure

((URAEMIA))

Etiology

1. Hypertension

2. DM

3. GN.

4. Cystic kidney diseases

eg. PKD

5. Interstitial renal diseases

6. Congenital

7. Systemic inflammatory diseases

eg. SLE

8. Unknown

Clinical presentations:

Asymptomatic

and discovered during routine examination to have raised

blood urea and serum creatinine

Nocturia

often an early symptom

3. Often accompanied by

hypertension

protienuria, anemia

, tiredness, fatigue

and anorexia.

Cardiovascular

manifestations: hypertension, peripheral oedema, arrhythmia,

pericarditis and pericardial effusion

GIT symptoms

: may be too early in form of nausea, vomiting, hiccoughs &GI

bleeding

Hematological

; fatigue, anemia, bleeding tendency.

Neurological

complications : muscular twitching, confusion, drowsiness, fit,

restless leg and comma.

dermatological

: pruritus, earthy color.

acute exacerbations

(acute on chronic) presented with metabolic acidosis and

Kussmaul respiration.

10. features of the

underlying cause

Investigations

CBP

: anemia (N.N., hypochromic microcytic or macrocytic)

↑

B,urea ,

↑

S. cr. ,

↑

K ,

↑

phosphate,

↓

ca,

↓

bicarbonate

3. Blood

sugar

and

lipid

profile

hepatitis

and

HIV

serology for dialysis or transplantation

X- ray

of the bones may shows features of secondary hyperparathyroidism (

ostitis fibrosa cystica)

6. abdominal

Ultrasonography

will show small size kidneys or any evidence of

obstructive uropathy

Chest X- ray

……Heart size , pulmonary edema

ECG

……..arrhythmia, pericarditis, IHD, Hyperkalemia

Tissue typing

if transplantation is considered

10.

Specific investigations

to identify the underlying cause eg. ANA for SLE

Management

A. Treatment of the underlying cause if possible eg. GN

B. Look for reversible factors which are making renal function worse

- hypertension

: antihypertensive drugs with BP goal of 130\85 mmHg

Obstructive uropathy

….Relieve the obstruction

urinary tract infection

..Vigorous treatment

Nephrotoxic medication

should be avoided eg. Tetracycline, Nalidixic acid,

aspirin, sulphonylurea, spirinolactone and acetazolamide.

C. Retarding the progression of CRF:

When serum createnin

>3.5 mg\dL

. , progressive deterioration in renal function

irrespective of its etiology and the rate of deterioration is very variable

between patients but it is constant for an individual patient and changes in

the slop may be achieved by:

Blood pressure

control.

2. Moderate

protein restriction

to 60 gm\day should be accompanied by

adequate intake of calories.

specific treatment

of the underlying cause eg. Immunosuppressive therapy for

GN.

D. Limiting the adverse effect of CRF:

1. regulation of fluid and electrolytes;

- Solute and fluid intake must be restricted

as renal failure advanced but those

with salt wasting disease may require a high sodium and water intake eg. Cystic

kidney diseases and tubulointerstitial diseases while those with glomerular

disease require restriction of sodium and water intake to avoid volume overload.

Diuretics

may be necessary if the patient is unable to restrict the sodium intake

adequately

correction of acidosis

with sodium bicarbonate supplement or in form of calcium

carbonate which also used to bind dietary phosphate.

Limitation of potassium intake

- In patient who are unable to maintain their volume status by diet and diuretics

or if they are persistently hyperkalaemic or severely acidotic,

dialysis therapy

indicated.

2.Correction of anemia;

Anemia is common in those with CRF and it may be result from:

Relative deficiency of erythropoietin

. Bon marrow depression

reduced intake and absorption of iron

↓ red cell survival

↑ blood loss ( bleeding, dialysis, sampling)

loss of foliate in dialysis

So correction of anemia usually achieved by

Recombinant human erythropoietin

folate supplement

Iron supplement should be used to keep serum ferritin >100ug.\L.

Androgen may be used in resistant cases

blood transfusion in refractory anemia.

3. Bleeding:

it is mostly due to impaired platelet function and adequate dialysis

partially correct bleeding tendency.

4. Infection

should be recognized and treated promptly

5. Cardiovascular diseases and lipid:

hypertension

develops in about

80%

of patients with CRF and it must be

controlled as it cause farther vascular and glomerular damage and

worsening of renal failure.

Hyperlipidemia

commonly seen and anti Hyperlipidemia (statine group)

achieve substantial reduction of lipid in chronic renal diseases.

6. Renal osteodystrophy :

it consist of mixture of

osteomalacia

hyperparathyroid

bone disease (ostitis

fibrosa cystica ),

osteoporosis

and

osteosclerosis

Its treatment:

. dietary

restriction of food

with high phosphate content (milk , cheese ,egg )

. use of

phosphate binding drugs

eg. Calcium carbonate.

1α – hydroxylated vitamin D

. In severe bone disease with autonomous parathyroid function ,

parathyroidectomy

may be necessary

7. Myopathy:

a. muscle cramps are common and

quinine sulphate

may be helpful

b. restless leg syndrome often improved by

clonazepam.

8.other adverse effects

a. neuropathy

: usually appear late and may improve or even resolve once

dialysis is established

b. amenorrhea

treated by dopamine agonists

c. GIT symptoms

treated symptomatically and there is higher incidence of peptic

ulcer diseases so H2 –receptor antagonists or proton pump inhibitors are

commonly used

d. depression

is common and psychological support should be provided for both

the patients and their families

E. RENAL REPLACEMENT THERAPY:

1. Haemodialysis:

In which there's diffusion of solutes between plasma and dialysate across a

synthetic semi-permeable membrane fallowing a concentration gradient.

movement of solutes may be bidirectional and continuo as long as the

concentration gradient remain.

Fluid is removed by applying negative pressure to the dialysate side ((

ultrafiltration)).

Vascular access is required and arteriovenous fistula should be formed.

Haemodialysis usually carried out of

3-4 hours

three times per week

but

usually start with

1 hour

and increase the time gradually to prevent

(( disequilibrium Syndrome ))

- It is

preferred in

patients with obesity, hernia, COPD, back pain, abdominal wall

scars and Hypoalbuminemia.

Anticoagulan

t are usually required.

2. Haemofiltration

- It involve the movement of large volumes of fluid across extremely porous

membranes

- It is effective therapy to

critically ill

or who is

haemodynamically unstable

patients.

3.Peritoneal dialysis

;

- Uses the peritoneum as a semi permeable dialysis membrane.

- Solute move down a concentration gradient and water down an osmotic

gradient achieved by

using an osmolar compound

((typically glucose)) in

the dialysis fluid.

- It is

preferred in

young children and elderly patient with cardiovascular

instability.

Peritonitis

is the most common complication

4.Renal transplantation:

- It offer the

best chance

of long term survival in patient with ESRD.

All patients

should be considered for transplantation

unless

there's

contraindication for it.

In the transplant operation, the donor vessels are anastomosed to the recipient

iliac artery and vein and the donor ureter to the bladder.

Contraindications;

1. Malignancy

2. Severe ischemic heart disease

3. Active vasculitis or anti GBM disease

4. Age less than 1 year or more than 75 years.

5. Significant comorbidity

Complications

The most common complication is graft rejection which is of 3 types:

1.Hyperacute rejection:

it occurs within min-hours of transplantation ((

incompatibility )).

2. Acute rejection:

it occurs 2-8 weeks after transplantation.

3. Chronic rejection:

it is more indolent and poorly responsive to antirejection

therapy.

- Immunosuppressive therapy

is required to prevent rejection using;

- Cyclosporine or tacrolimus

- azathioprime

- predenselon

- sepsis

is an important complication.

GOOD LUCK

GOOD BYE