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1. CHRONIC RENAL FAILURE BY DR MAGDI AWAD SASI 2014 part 3 RF
CHRONIC RENAL FAILURE
Definition:
It is a long term decline in kidney function.
Acute on chronic renal failure—a patient with diagnosed or undiagnosed CRF
with some remaining RF & subjected to acute insult ie infection ,dehydration ,
obstruction …etc , causing rapid deteroration of RF with s&s of uremia.
CRITERIA FOR DIAGNOSIS:
The major criterion is a slow inexorable rise in the serum BUN and creatinine.
1. Most diseases that cause CRF usually appear as ARF.
A. A renal biopsy may be performed while the patient is examined at ARF.
B. When a chronic process is suspected or the creatinine level ˃5 micgm/dl ; a biopsy is
seldom helpful and show chronic GN/ diffuse scarring.
2. USS abdomen---- can examine renal size and estimate functional reserve --- small
scarred or contracted kidney.
3. Three stages of CRF may be identified.
I. Renal insufficiency---maliase ,nocturia ,anemia
II. Frank renal failure---- progressive acidosis ,hypocalcemia
,hyperphosphatemia , worsening anemia
III. Uremia or end stage renal disease
GFR ˃5cc/min + severe symptoms + require dialysis
MAJOR CAUSES OF CRF:
I. GLOMERULAR DISEASE----60%
1. Nephrotic causes:
GN- Glomerulonephritis—(( membranous ,membranoproliferative ,chronic non
specific)) ,Focal glomerulosclerosis
2. Nephritic causes:

2. CHRONIC RENAL FAILURE BY DR MAGDI AWAD SASI 2014 part 3 RF
Post infectious GN , crescentric GN ,IgA nephropathy ,Good Pasteurs syndrome ,
proliferative GN , secondary GN (( PAN , SLE ,amyloidosis , diabetic
glomerulosclerosis)).
II. CONGENITAL AND INHERITED DISEASES:
Polycystic kidney disease
Medullary cystic disease
Alports syndrome
Congenital hypoplasia
III. VASCULAR DISEASE:
Arteriosclerosis
Malignant HTN
Bilateral renal artery sclerosis
Diabetic nephropathy
Wegners granulomatosis
Polyarteritis nodosa
Fibromuscular hyperpalsia
IV. TUBULAR DISEASE ( interstitial ):
Heavy metal poisoning –lead ,cadmium
Chronic hypercalcemia --nephrocalcinosis , hypokalemia
Analgesic nephropathy
Uric acid nephropathy
Multiple myeloma
tuberculosis
Amyliodosis
Fanconis syndrome
V. INTRINSIC URINARY TRACT DISEASE:
Chronic pyelonephritis
Chronic urinary tract infection—stones ,clots ,pus ,tumours
Lower tract obstruction
VI. OBSTRUCTIVE UROPATHY:
Calculus
Retroperitoneal fibrosis
Prostatic hypertrophy
Pelvic tumour
VII. CAUSE OF ARF:
10-15% of cause of ARF advances to CRF & ESRD.

3. CHRONIC RENAL FAILURE BY DR MAGDI AWAD SASI 2014 part 3 RF
FACTORS THAT ACCELERATE END STAGE RENAL DISEASE:
Any patient with rapidly rising creatinine & BUN ; when the patient
previously had a slow defined rate of increase ; should be evaluated:
1. Urinary tract obstruction:
 Seen when obstruction was the orginal cause of CRF.
 Uremic pt may also have bladder neck dysfunction and obstructive urethral
edema after instrumentation.
 S & S are frequently absent.
2. Urinary tract infection:
100% CRF pt will be infected at sometime & universally after instrumentation.
3. Volume depletion:
Is a common problem in early renal insufficiency when the ability to conserve NA
may be lost.
NA loss----Diuretic ,Diarrhea ,Vomiting ,Fever , Exercise .
4. Hypokalemia:
More common in CRF
K-excreting ability is preserved until quite late in the course of CRF.
Hyperkalemia----sign of far advanced uremia
COMPLICATION OF CRF
A. ANEMIA:
Type – normoocytic normochromic ,microcytic hypochromic
Causes :
1. Decrease Erythropiotein production
2. Faster turnover of RBC
3. Uremic hemolytic effect
4. Decrease RBC life span
5. Toxic effect on bone marrow
6. Blood loss during dialysis
7. Bleeding tendency
Course ---usually early in the course of renal insufficiency w HCT 25-32% HCT
should be done. Serum iron and transferin levels which reveal peripheral block to iron
utilization . ferritin usually accumulate in CRF WITH LOW SERUM IRON .

4. CHRONIC RENAL FAILURE BY DR MAGDI AWAD SASI 2014 part 3 RF
Anemia can be caused by:
1. Clotting disorders
2. Platelet disorders
3. Occult bleeding
B. PLATELET AND CLOTTING DISORDERS:
1. CRF is often accompanied by:
I. Acquired von willebrands disorders
II. Factor III & platelet dysfunction
2. These problems are generally observed in advanced uremia , BUN ((
100—150 mg/dl)) + creatinine (˃10mg /dl)
3. They are aggravated by aspirin and infection
4. Antibiotics (cefamandole ,moxalactam) affecting VIT K dependent
factors should be avoided.
5. Diagnosis by:
Platelet count , bleeding time ,prothrombin ,partial thromboplastin
C. Peripheral neuropathy:
1. Occurs in advanced RF ,PARTIALLY REVERSIBLE BY DIALYSIS ,toxin related
2. Diagnosis by careful examination of vibration sense , touch sense ,
postion sense.
3. Nerve conduction studies confirm diagnosis.
D. Aluminium toxicity dementia:
1. It is degenerative disorder due to aluminium deposition in the CNS
2. May occur prior to dialysis in patient with advanced uremia if they are
consuming aluminium containing antacids for months –years.
3. Manifesting by suttering dysphagia that progress to aphasia, seizures,
disorientation.
Hem dialysis aggravates this.
4. It is difficult to get s.aluminium.
Be aware for: ---
Ca supplement

5. CHRONIC RENAL FAILURE BY DR MAGDI AWAD SASI 2014 part 3 RF
Look for the onset
Patient response to vit D metabolites
Aluminium supplements
Clinical diagnosis -- history and finding.
E. Metabolites complications:
1. Uremia patients develop peripheral insensitivity to insulin causing
glucose intolerance and hyperinsulinism.
2. Hyperlipidemic stat---( increase VLDL)--- is characterized of uremia due
to inhibition of lipoprotein lipase and hyperinsulinism .
3. Decrease dose of insulin in diabetic because of decrease renal clearance
F. Vascular complication:
1.HTN:
Difficult to control unless dialysis initiated
HTN in CRF is due to
I.Chronic volume overload
II.Increased peripheral vascular resistance B/C altered vascular tone.
2.Pericardial disease:
.ECHO may assist in the diagnosis of all pericardial disease.
.Pericardial disease common B/C haemodialysis and intermittent anticoagulant.
A. AUTE PARICARDITIS:
.Common complication of uremia
.Respond to dialysis
.Symptoms--- fever + pleuritic chest pain
. A TWO OR THREE component friction rub is present in all patients.
B. CARDIAC TEMPONADE:
I. May cause significant fall in BP during dialysis.
II. Distant heart sounds
Monophysiologically elevated neck veins
Pulsus paradoxus (( ˃15---20 mmhg )) 70%--80% of pt
III. Right heart catheterization :
Equalization of diastolic pressure in all chambers.

6. CHRONIC RENAL FAILURE BY DR MAGDI AWAD SASI 2014 part 3 RF
C. CHRONIC CONSTRICTIVE PERICARDITIS:
 NECK VEINS –elevated , kussmauls sign , inspiratory increase
 There may be a pericardial knock caused by ventricular
constriction at the end of diastole.
 Pulsus paradoxus is rarely present.
3.Atherosclerosis:
Results from :
 Glucose intolerance
 Poorly controlled HTN
 Hyperlipedemia
 High prevelance of smoking
G. INFECTION:
1.Uremia inhibit phagocytic ability and causes T cell deficiency predisposing
to bacterial and viral infection
2.fever is often suppressed in uremia
The most frequent serious side infections :
Staphylococcal septicemia
Staphylococcal abscess in urinary tract (( perinephric))
Osteomyelitis
Endocarditis
Hepatitis B
Herpes zoster
H. RENAL OSTEODYSTROPHY:
Patient with hypocalcemia and hyperphosphatemia , hand radiographs
should be obtained to screen for the onset of osteodystrophy.
Radioimmunoassay for N. terminal (( PTH)) may be obtained to
demonstrate 2ry hyperarathyrodism.
Degree and type of disease require above biopsy with special stains .
WHAT IS THE RECOMMENDED DIAGNOSTIC APPROACH?
Factors that accelerate CRF :
1. Urinary tract obstruction:
USS abdomen & pelvis is indicated if BUN & creatinine have suddenly increased.
2. Urinary tract infection:
Microscopic examination of urine for WBC , RBC and bacteria is imperative.

7. CHRONIC RENAL FAILURE BY DR MAGDI AWAD SASI 2014 part 3 RF
AS RF PROGRESS ; URINANALYSIS LESS HELPFUL.
3. Volume depletion:
Postural change in blood pressure and pulse may suggest volume depletion.
It is non specific finding in diabetic pt B/C of autonomic neuropathy.
NOTE:
IN A PATIENT WITH HTN OR DM OR RISK FOR RF, IF THE PATIENT
PRESENT WITH MULTISYSTEM SYMPTOMS , C.RENAL FAILURE SHOULD
BE EXCLUDED.
In CRF , THE FOLLOWING ARE MANDATORY FOR DX:
1. SYSTEMIC SYMPTOMS OF CHRONIC DURATION
2. ANEMIA
3. HYPERKALEMIA
4. HYPOCALCEMIA
5. HYPERPHOSPHATEMIA
6. USS ABDOMEN - SMALL SHRINKED SCARRED KIDNEYS EXCEPT PCKD
Emergency investigations:
Blood glucose
Renal function tests and electrolytes
Liver function test
Full blood count
Uss abdomen and pelvis
24 hour collection of urine for creatinine clearance
Lipid profile
Coagulation screen
Urine microscopy and culture
Blood culture
Chest x ray

8. CHRONIC RENAL FAILURE BY DR MAGDI AWAD SASI 2014 part 3 RF
Calcium and phosphate
ECG
Serology
The major complications:
1. Hypertensive crises:
Fluid over load
Diseases—TTP/HUS , glomerulonephritis
2. Metabolic emergencies:
Severe uremia
Hyperkalemia
Severe acidosis
Hyponatremia h
Hypocalcemia
Hyperphosphatemia.
3. Respiratory failure:
Pulmonary edema – fluid overload
Cardiogenic
ARDS
Pulmonary infection
Lung contusion
Flail chest
Pneumothoraces ,
Aspiration
Emboli –fat ,blood clots .
4. Shock :
Hypovolemia ,cardiogenic ,septic