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CHRONIC RENAL FAILURE

Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

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The lecture has been given on Dec. 5th, 9th & 11th, 2010 by Dr. Kawa Husain.

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Page 1: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

CHRONIC RENAL FAILURE

Page 2: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

CHRONIC RENAL FAILURE

Chronic renal failure (CRF) refers to an irreversible deterioration in renal function which classically develops over a period of years .

Page 3: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

• Initially, CRF manifest only as a biochemical abnormality.

• Eventually, loss of the excretory, metabolic and endocrine functions of the kidney leads to the development of the clinical symptoms and signs of renal failure, which are referred to as uraemia.

• End stage renal disease (ESRD):renal failure which need renal replacement therapy.

• When death is likely without renal replacement therapy, it is called end-stage renal failure (ESRF).

Page 4: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Aetiology of CRF

• CRF may be caused by any condition which destroys the normal structure and function of the kidney.

• Patients often have bilateral small kidneys at presentation, and in such a situation renal biopsy is usually inadvisable because of the difficulty in making a histological diagnosis in severely damaged kidneys and the fact that treatment is unlikely to improve renal function significantly.

Page 5: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Common causes of Chronic Renal Failure

• Diabetes Mellitus • Hypertension • Glomerulonephritis• Chronic pylonephritis/reflux 10%• Polycystic kidney disease• Interstitial nephritis• Obstruction• Unknown

Page 6: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Hypertension

Chronic Glomerulonephritis

Diabetes (most common cause)

Polycystic Kidney Disease

Page 7: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Pathogenesis of CRF

• Disturbances in water, electrolyte and acid-base balance contribute to the clinical picture in patients with CRF, but the exact pathogenesis of the clinical syndrome of uraemia is unknown.

• Many substances present in abnormal concentration in the plasma have been suspected as being 'uraemic toxins', and uraemia is probably caused by the accumulation of various intermediary products of metabolism.

Page 8: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Clinical Features of CRF

Page 9: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Major manifestations of Uremic Syndrome

The Uremic Syndrome:Gastrointestinal -Anorexia , Nausea , Vomiting , Disturbance of taste , Gastritis

Peptic ulcer , GI bleeding.Cardiovascular - Cardiomegally , arrhythmias , pericarditis , accelerated

atherosclerosis.Pulmonary -Pneumonitis , pleuritis, pleural effusion , non-cardiogenic

pulmonary oedema.Haematologic - Anaemia , bleeding disorders , leukocyte dysfunction.

Page 10: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Skin -Pruritus , yellow pigmentation , earthy colour face.Musculoskeletal -Muscle weakness , gout & pseudogout , renal osteodystrophy .Endocrine / Metabolic -Hyperparathyroidism , amenorrhea , impotence , hyperlipidemia increased

insulin resistance.

Acid base / Electrolytes -Acidosis , hyperkalemia , fluid overload , hypocalcemia , hyperphosphatemia ,

hypermagnesemia.

Nervous system -Central : irritability , insomnia , lethargy , seizures , coma. -Peripheral : glove-and stocking sensory loss , restless leg , foot drop or

wrist drop.

Page 11: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Clinical assessment

• Renal failure may present as a raised blood urea and creatinine found during routine examination, often accompanied by hypertension, proteinuria or anaemia.

• When renal function deteriorates slowly, patients may remain asymptomatic until GFR falls below 20 - 30 ml/minute( normal range 80 – 120 mL/ min ).

• Nocturia, due to the loss of concentrating ability and increased osmotic load per nephron, is often an early symptom.

• Thereafter, due to the widespread effects of renal failure, symptoms and signs may develop that are related to almost every body system .

Page 12: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

• Patients may present with complaints which are not obviously renal in origin, such as tiredness or breathlessness.

• In ESRF (stage 5) patients appear ill and anaemic.

• There may be unusually deep respiration related to metabolic acidosis (Kussmaul's respiration), anorexia and nausea.

• Later, hiccoughs, pruritus, vomiting, muscular twitching, fits, drowsiness and coma ensue.

Page 13: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

• Specific manifestations of Uremia

Page 14: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Specific manifestations of Uremia

• Gastrointestinal manifestations

• Are common at low GFRs, including: • anorexia followed by nausea, and vomiting is commonly seen. • There is a higher incidence of peptic ulcer disease in uraemic

patients.

Page 15: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Anaemia

• Anaemia is common in CRF; it usually correlates with the severity of renal failure and contributes to many of the non-specific symptoms of CRF.

• Several mechanisms are implicated(causes of anaemia inCRF): 1- Relative deficiency of erythropoietin 2- Diminished erythropoiesis due to toxic effects of uraemia on

marrow precursor cells 3- Reduced red cell survival 4- Increased blood loss due to capillary fragility and poor platelet

function 5- Reduced dietary intake and absorption of iron and other

haematinics.

Page 16: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

• Plasma erythropoietin is usually within the normal range and thus inappropriately low for the degree of anaemia.

• In patients with polycystic kidneys, anaemia is often less severe or absent, while in some interstitial disorders it appears disproportionately severe for the degree of renal failure. This is probably because of the effects of these disorders on the interstitial fibroblasts that secrete erythropoietin

Page 17: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Acidosis

Declining renal function is associated with metabolic acidosis , which is often asymptomatic. There may be unusually deep respiration related to metabolic acidosis (Kussmaul's respiration).

Effects of metabolic acidosis :• Sustained acidosis results in protons being buffered in

bone in place of calcium, thus aggravating metabolic bone disease.

• Acidosis may also contribute to reduced renal function and increased tissue catabolism.

Page 18: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Cardiovascular disease and lipids

• CRF is an independent risk factor for occlusive cardiovascular disease.

• Hypertension develops in approximately 80% of patients with CRF.

In part, this is caused by sodium retention. Chronically diseased kidneys also tend to hypersecrete renin, leading to

high circulating concentrations of renin, angiotensin II and aldosterone.

This is exaggerated if there is renal under-perfusion related to renal vascular disease.

Hypertension must be controlled, as it causes further vascular and glomerular damage and worsening of renal failure

• Atherosclerosis is common and may be accelerated by hypertension.

Page 19: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

• Pericarditis is common in untreated or inadequately treated ESRF.

It may lead to pericardial tamponade and, later, constrictive pericarditis.

• Hypercholesterolaemia is almost universal in patients with significant proteinuria, and

increased triglyceride levels are also common in patients with CRF.

It has been suggested that as well as influencing the development of vascular disease, this may accelerate the

progression of chronic renal disease.

Page 20: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Renal osteodystrophy

• This metabolic bone disease which accompanies CRF consists of a mixture of osteomalacia, hyperparathyroid bone disease (osteitis fibrosa), osteoporosis and osteosclerosis .

Osteomalacia • Results from diminished activity of the renal 1α-

hydroxylase enzyme, with failure to convert cholecalciferol to its active metabolite, 1,25-dihydroxycholecalciferol.

• A deficiency of the latter leads to diminished intestinal absorption of calcium, hypocalcaemia and reduction in the calcification of osteoid in bone.

Page 21: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

• Osteitis fibrosa results from this secondary hyperparathyroidism .

• The parathyroid glands are stimulated by the low plasma calcium, and also by hyperphosphataemia.

• In some patients tertiary or autonomous hyperparathyroidism with hypercalcaemia develops.

• Osteoporosis occurs in many patients , possibly related to malnutrition.

• Osteosclerosis is seen mainly in the sacral area, at the base of the skull and in the vertebrae; the cause of this unusual reaction is not known.

Page 22: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Myopathy

• Generalised myopathy is due to a combination of poor nutrition, hyperparathyroidism, vitamin D deficiency and disorders of electrolyte metabolism.

• Muscle cramps are common, and quinine sulphate may

be helpful.

• The 'restless leg syndrome', in which the patient's legs are jumpy during the night, may be troublesome and is often improved by clonazepam

Page 23: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Neuropathy• Neuropathy results from demyelination of medullated fibres, with

the longer fibres being involved at an earlier stage.

• Sensory neuropathy may cause paraesthesiae. Amitriptyline and gabapentin may provide some symptom relief.

• Motor neuropathy may present as foot drop.

• Uraemic autonomic neuropathy may cause delayed gastric empty-ing, diarrhoea and postural hypotension.

• Clinical manifestations of neuropathy appear late in the course of CRF but may improve or even resolve once dialysis is established.

Page 24: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Endocrine Function

A number of hormonal abnormalities may be present of which the most important are hyperprolactinaemia & hyperparathyroidism .

• In both sexes there is loss of libido and sexual function, related at least in part to hyperprolactinaemia .

In women amenorrhoea is common.• The half-life of insulin is prolonged in CRF due to reduced

tubular metabolism of insulin; insulin requirements may therefore decline in diabetic patients in end-stage CRF.

• However, there is also a post-receptor defect in insulin action, leading to relative insulin resistance.

• This latter abnormality is improved by dialysis treatment.

Page 25: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Bleeding

• There is an increased bleeding tendency in renal failure which manifests in patients with advanced disease as cutaneous ecchymoses and mucosal bleeds.

• Platelet function is impaired and bleeding time prolonged.

• Adequate dialysis treatment partially corrects the bleeding tendency.

Page 26: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Infection

• Cellular and humoral immunity are impaired, with increased susceptibility to infection.

• Infections are the second most common cause of death in dialysis patients, after cardiovascular disease; they must be recognised and treated promptly.

Page 27: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Acute or Chronic?

• History• Previous renal function test.• Small kidneys on u/s• Anaemia.• Bone changes.

Page 28: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Acute or Chronic Renal failure?

• History• Previous renal function test.• Small kidneys on u/s• Anaemia.• Bone changes.

Page 29: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

• Investigations and management of CRF

Page 30: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Investigations and management of CRF

• There are several aspects to the management of CRF:

• Identify the underlying renal disease. • Look for reversible factors which are making renal

function worse . • Attempt to prevent further renal damage. • Attempt to limit the adverse effects of the loss of renal

function. • Institute renal replacement therapy (dialysis or

transplantation)

Page 31: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

.At presentation the nature of the underlying disease should be determined, if possible, by

history, examination, testing of biochemistry, immunology, radiology and biopsy .

• The degree of renal failure is assessed and complications are documented.

Page 32: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Investigations

-Blood urea & serum creatinine : increased- Serum electrolytes .serum calcium :decreased .serum potassium : increased ( risky ) .serum uric acid : increased(but rarely cause gout ) .serum phosphate : increasedGeneral urine examination: for: protein , RBC , features of UTI ( may

need urine culture ) , cast ( waxy broad cast is characteristic for CRF)Complete blood picture: usually there is anaemia. PH of blood : metabolic acidosis.Viral markers : HBsAg , Anti-HCV Ab & HIV test (if dialysis is needed)

(vaccination against hepatitis B if no previous infection; isolation of dialysis machine if positive) .

Page 33: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

ECG: look for -Features of hyperkalemia (hyperacute T- wave ,then prolongation

of PR- interval & QRS ,then loss of P-wave , & if not managed may cause asystole )

-Features of pericardial effusion( low voltage ECG ). -Features of IHD.Echocardiography: look for any evidence of pericardial effusion or cardiomyopathy ( DCMP).CXR: look for features of pulmonary oedema , pleural effusion , chest

infection , enlarged cardiac shadow.Abdominal Ultrasoud : look for the size & ecchogenecity of the

kidneys & if there is ascitis. In CRF , usually bilateral small kidneys (except polycystic kidney

disease , amyloidosis , hydronephrosis , diabetic nephropathy )

Page 34: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

X- ray of bone : for evidence of renal osteodystrophy.

Renal biopsy : only indicated in CRF with normal size kidneys ( not indicated in CRF with small size kidneys ).

• GFR• If diagnosis is not known further investigation needed as :• Immunoglobulins and protein electrophoresis • Urinary Bence Jones protein • Complement • ANA: and dsDNA if ANA is positive • Rheumatoid factor • ANCA: in all possible inflammatory renal disease • Anti-GBM: in all possible inflammatory renal disease • Cryoglobulins: if cryoglobulinaemia is clinically suspected

Page 35: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Hyperkalemia & EKG• K > 5.5 -6• Tall, peaked T’s• Wide QRS• Prolong PR• Diminished P• Prolonged QT• QRS-T merge – sine

wave

Page 36: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)
Page 37: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Stage Description GFR (ml/min/1.73 m2)

1 Kidney damage with normal or GFR

90

2 Kidney damage with mild GFR 60-89

3 Moderate GFR 30-59

4 Severe GFR 15-29

5 Kidney failure < 15 (or dialysis)

Chronic Kidney Disease Staging

Page 38: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Retarding the progression of CRF

• Unless dialysis or transplantation is provided , CRF is eventually fatal.

• Once the plasma creatinine exceeds about 300 μmol/l (3.4 mg/dl), there is usually progressive deterioration in renal function, irrespective of aetiology.

• The rate of deterioration is very variable between patients but is relatively constant for an individual patient.

Page 39: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

REVERSIBLE FACTORS IN CHRONIC RENAL FAILURE

1- Hypertension 2- Reduced renal perfusion

– Renal artery stenosis – Hypotension due to drug treatment – Sodium and water depletion – Poor cardiac function

3- Urinary tract obstruction 4- Urinary tract infection 5- Other infections: increased catabolism and urea production 6- Nephrotoxic medications

• CRF is usually irreversable , by controlling the reversable factors we may delay the progression of renal impairement to ESRD.

Page 40: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Control of blood pressure

In many types of renal disease, particularly in diseases affecting glomeruli (particularly those associated with heavy proteinuria), control of blood pressure may retard deterioration of GFR & delay the progression to ESRD.

The target blood pressures is 130/85 mmHg for CRF alone, & lowered to 125/75 mmHg for those with proteinuria > 1 g/day.

Drugs can be used :ACE inhibitors like captopril Angiotensin II receptor antagonists like valsartan calcium channel blockers like diltizem

Page 41: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

• ACE inhibitors like captopril have been shown to be more effective at retarding the progression of renal failure , because they reduce glomerular perfusion pressure by dilating the efferent arteriole & reduce proteinuria

• ACE inhibitors should be used, where tolerated (check creatinine and potassium), in all patients with diabetic nephropathy or protein-uria > 1 g/day independent of the presence of hypertension.

• Using ACE inhibitors need monitoring of serum potassium. • ACE inhibitors should not be used when there is renal artery

stenosis

Page 42: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Diet

Dietary proteinFor patients on renal replacement therapy , severe protein

restriction is not recommended because carry a risk of inducing malnutrition.

Moderate restriction (to 60 g protein per day) should be accompanied by an adequate intake of calories calories(30-35kcal/kg/d) to prevent malnutrition.

Anorexia and muscle loss may indicate a need to commence dialysis treatment.

Page 43: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Treatment of Anaemia of CRF

Recombinant human erythropoietin (Eprex ) is effective in correcting the anaemia of CRF .

dose : 50 Iu / kg once or twice wk.ly route : subcutaneously (or IV for patients on haemodialysis ). The target haemoglobin is usually between 10 and 12 g/dl.

Complications of treatment include increased blood pressure, and adjustment of antihypertensive medication is often necessary. There is also an increase in blood coagulability and an increased incidence of thrombosis of the arteriovenous fistulae used for haemodialysis.

Page 44: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Erythropoietin is less effective in the presence of :iron deficiency, active inflammation or malignancy, or in patients with

aluminium overload which may occur in dialysis. Causes of Erythropoietin resistant• Iron deficiency• Active inflamation• Malignancy• Secondary hyperparathyroid• Aluminum overload• Pure red cell aplasia

These factors should be sought and, if possible, corrected before treatment.

Iron supplementation should be used to keep ferritin > 100 μg/l and transferrin saturation > 20%.

Page 45: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Fluid and electrolyte balance• Due to the reduced ability of the failing kidney to concentrate the

urine, a relatively high urine volume is needed to excrete products of metabolism and a fluid intake of around 3 litres/day is desirable

( when there is no fluid overload “ no oedema “ ) fluid retention sometimes lead to episodic pulmonary oedema .

• Fluid intake:urine volume +500ml

.Limitation of potassium intake (e.g. 70 mmol/day) and sodium intake (e.g. 100 mmol/day) may be required in late CRF if

there is evidence of accumulation.Low phosphate diet(600-1000mg/d)

Page 46: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Hyperkalemia Treatment• Calcium gluconate • Sodium Bicarbonate• Insulin/glucose• Sodium bicarbonate• Frusemide• Salbutamol• Hemodialysis

Page 47: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

• Some patients with so-called salt-wasting' disease may require a high sodium and water intake, including supplements of sodium salts, to prevent fluid depletion and worsening of renal function.

• This is most often seen in patients with renal cystic disease, obstructive uropathy, reflux nephropathy or other tubulo-interstitial diseases, and is not seen in patients with glomerular disease.

Page 48: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Treatment of Acidosis

• The plasma bicarbonate should be maintained above 22

mmol/l by giving sodium bicarbonate supplements (starting dose of 1 g 8-hourly, increasing as required).

• The increased sodium intake may induce hypertension or oedema.

• calcium carbonate (up to 3 g daily) is an alternative that is also used to bind dietary phosphate.

Page 49: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Treatment of Hypercholesterolaemia

• Statin ( as simvastatin ) achieve substantial reductions in lipids in chronic renal disease.

• Hyperlipidemia is more if the CRF is due to glomerular diseases due to the increased hepatic lipoprotein synthesis that is triggered by reduced oncotic pressure

Page 50: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Treatment of Bleeding

• Adequate dialysis treatment partially corrects the bleeding

tendency.

Page 51: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Renal osteodystrophy

• To minimise the effects of CRF on bone, plasma calcium and phosphate should be kept as near to normal as possible.

• Treatment of Hypocalcaemia • is corrected by giving 1α-hydroxylated synthetic analogues of

vitamin D. The dose is adjusted to avoid hypercalcaemia. This will usually prevent or control osteomalacia.

• .

Page 52: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

• Treatment of Hyperphosphataemia • Is controlled by dietary restriction of foods with high

phosphate content (milk, cheese, eggs)• The use of phosphate-binding drugs administered with

food. • These agents form insoluble complexes with dietary

phosphate and prevent its absorption (e.g. calcium carbonate 500 mg with each meal and aluminium hydroxide 300 – 600 mg before each meal).we should avoid aluminium toxicity.

• Secondary hyperparathyroidism is usually prevented or controlled by these measures but, in severe bone disease with autonomous parathyroid function, parathyroidectomy may become necessary

Page 53: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Treatment of renal osteodystropy Vitamin D (0.25ug/d for prophylactic, 0.5ug/d

for symptomatic, pulse therapy 2-4ug/d for severe cases)

Low phosphate diet Calcium carbonate (1-6g/d) parathyroidectomy

Page 54: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Treatment of Myopathy

• Muscle cramps are common, and quinine sulphate may be helpful.

• The 'restless leg syndrome', in which the patient's legs are jumpy during the night, may be troublesome and is often improved by clonazepam

Page 55: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Treatment of Neuropathy

• Clinical manifestations of neuropathy appear late in the course of CRF but may improve or even resolve once dialysis is established.

• Sensory neuropathy may cause paraesthesiae. Amitriptyline

and gabapentin may provide some symptom relief.

Page 56: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Treatment of Endocrine disorders

• Treatment with dopamine agonists is sometimes useful

for amenorrhoea or galactorrhoea in women

• Insulin requirements usually decline in diabetic patients in end-stage CRF ( CRF patients are liable for hypoglycemia ).

• insulin resistance is improved by dialysis treatment.

Page 57: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Gastrointestinal manifestations

• Are common at low GFRs, including anorexia followed by nausea, and vomiting is commonly seen & improve by dialysis.

• There is a higher incidence of peptic ulcer disease in uraemic patients and H2-receptor antagonists or proton pump inhibitors are commonly used.

Page 58: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Depression

• Depression is common in patients on or approaching renal replacement therapy and support should be provided for both them and their relatives

Page 59: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

• RENAL REPLACEMENT THERAPY

Page 60: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

RENAL REPLACEMENT THERAPY

• Dialysis ( Haemodialysis , Peritoneal ).• Renal transplantation.

Page 61: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

RENAL REPLACEMENT THERAPY

• The facility to replace some functions of the kidney artificially by dialysis has been available since the 1960s.

• Such treatment is now routine in patients with acute or chronic renal failure.

• It does not replace the endocrine and metabolic functions of the kidney, but aims to maintain the plasma biochemistry (uraemic toxins, electrolytes and acid-base status) at acceptable levels.

• Dialysis can also remove fluid from the circulation (ultrafiltration) to maintain euvolaemia.

Page 62: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Haemodialysis• Haemodialysis is started when the patient has symptomatic advanced

renal failure but before the development of serious complications, often with a plasma creatinine of 600-800 μmol/l (6.8-9.0 mg/dl).

• Vascular access is required; an arteriovenous fistula should be formed, usually in the forearm, when the patient reaches stage 4 kidney disease, so that the fistula has time to develop.

• After 4-6 weeks, increased pressure in the vein leading from the fistula causes distension and thickening of the vessel wall (arterialisation).

• Large-bore needles can then be inserted into the vein to provide access for each haemodialysis treatment

• If this access is not possible, plastic cannulae in central veins can be used for short-term access

Page 63: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

• Haemodialysis is usually carried out for 3-5 hours, three times weekly.

• Most patients notice an improvement in symptoms during the first 6 weeks of treatment.

• Plasma urea and creatinine are lowered by each treatment but do not return to normal.

• Many patients lead normal and active lives, and patient survival for more than 20 years is commonplace in young patients without extrarenal disease.

Page 64: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Hemodialysis• 3-4 times a week• Takes 3-5 hours • Machine filters blood and returns it to body

Page 65: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

AV Fistula & Graft

Page 66: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Temporary Catheter

Page 67: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Hemodialysis

Page 68: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Hemodialysis

AV Fistula CommunicationAV Fistula Communication

AV Graph AccessAV Graph Access

Page 69: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Hemodialysis

Hemodialysis MachineHemodialysis MachineHemodialysis CircuitHemodialysis Circuit

Page 70: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

PROBLEMS WITH HAEMODIALYSIS

• Hypotension during dialysis • Cardiac arrhythmias • Haemorrhage Blood loss (overt or occult), ↓BP• Air embolism Circulatory collapse, cardiac arrest • Dialyser hypersensitivity Acute circulatory collapse , may be due to Allergic reaction to

dialysis membrane or sterilisant

• Other Emergencies conditions • Pulmonary oedema ,Systemic sepsis, Breathlessness ,Rigors, fever.

Page 71: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Hemo Advantages & Disadvantages

Rapid fluid removalRapid removal of

urea & creatinineEffective K+ removalLess protein lossHome dialysis

possibleTemporary access at

the bedside

Rapid fluid removalRapid removal of

urea & creatinineEffective K+ removalLess protein lossHome dialysis

possibleTemporary access at

the bedside

Vascular access problems

Dietary & fluid restrictions

HeparinizationExtensive equipmentHypotensionAdded blood lostTrained specialist

Vascular access problems

Dietary & fluid restrictions

HeparinizationExtensive equipmentHypotensionAdded blood lostTrained specialist

AdvantagesAdvantages DisadvantagesDisadvantages

Page 72: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Contraindications of HD

• Shoke• Severe caidiac complications• Severe bleeding• malignency , sepsis• poor condition in vascular system

Page 73: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Peritoneal dialysis

• Peritoneal dialysis uses peritoneum as a semi-permeable dialysis membrane.

• Solutes move down a concentration gradient, and water down an osmotic gradient achieved by using an osmolar compound (typically glucose) in the dialysis fluid.

Page 74: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

PD Advantages and Disadvantages

Immediate initiationLess complicatedPortable (CAPD)Fewer dietary

restrictionsShort training timeLess cardio stressChoice for diabetics

Immediate initiationLess complicatedPortable (CAPD)Fewer dietary

restrictionsShort training timeLess cardio stressChoice for diabetics

Bacterial/chemical periotonitis

Protein lossExit site of catheterHyperglycemiaSurgical placement of

catheterMultiple abdominal

surgery

Bacterial/chemical periotonitis

Protein lossExit site of catheterHyperglycemiaSurgical placement of

catheterMultiple abdominal

surgery

AdvantagesAdvantages DisadvantagesDisadvantages

Page 75: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Continuous ambulatory peritoneal dialysis (CAPD)

• CAPD is a form of long-term dialysis involving insertion of a permanent Silastic catheter into the peritoneal cavity.

• Two litres of sterile, isotonic dialysis fluid are introduced and left in place for approximately 6 hours.

• During this time, metabolic waste products diffuse from peritoneal capillaries into the dialysis fluid down a concentration gradient.

• The fluid is then drained and fresh dialysis fluid introduced. • This cycle is repeated four times daily, during which time the patient is

mobile and able to undertake normal daily activities.• CAPD is particularly useful in young children, and in elderly patients with

cardiovascular instability.• Its long-term use may be limited by episodes of bacterial peritonitis and

damage to the peritoneal membrane, but patients have been treated successfully for more than 10 years.

Page 76: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Automated peritoneal dialysis (APD)

• The use of automated peritoneal dialysis (APD) is now widespread.

• This system is similar to CAPD but uses a mechanical device to perform the fluid exchanges during the night, leaving the patient free, or with only a single exchange to perform, during the day.

Page 77: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

PROBLEMS WITH CONTINUOUS AMBULATORY PERITONEAL DIALYSIS (CAPD)

• peritonitis Cloudy drainage fluid; abdominal pain and systemic sepsis are

variable Usually entry of skin contaminants via catheter; bowel organisms less common

• Catheter exit site infection Erythema and pus around exit site Ultrafiltration failure Fluid overload ,Damage to peritoneal membrane, leading to rapid

transport of glucose and loss of osmotic gradient Peritoneal membrane failure Inadequate clearance of urea etc. Scarring/damage to peritoneal

membrane.

Page 78: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Choice of HD or CAPD

poorbetterEcnomic situation

poorgoodVascular condition

BleedingNo bleedingBlood

yesnoCardiovascular disease

eldlyyoungAge

PDHD

Page 79: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Renal transplantation

Renal transplantation offers the best chance of long-term survival in patients with end-stage renal disease.

It can restore normal kidney function and correct all the metabolic abnormalities of CRF.

All patients should be considered for transplantation unless there are active contraindications

Page 80: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

• Kidney grafts may be taken from a cadaver or from a living donor. • matching of a donor to a specific recipient is strongly influenced by

immunological factors, since graft rejection is the major cause of failure of the transplant.

• ABO (blood group) compatibility between donor and recipient is essential, and the degree of matching for major histocompatability (MHC) antigens-particularly HLA-DR-influences the incidence of rejection.

• In the transplant operation, the donor vessels are anastomosed to the recipient iliac artery and vein, and the donor ureter to the bladder

• Peri-operative problems include: Fluid balance. Careful matching of input to output is required.

• Primary graft non-function. Causes include hypovolaemia, acute tubular necrosis or other pre-existing renal damage, hyperacute rejection, vascular occlusion and urinary tract obstruction.

• Sepsis (related to immunosuppression).

Page 81: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

CONTRAINDICATIONS TO RENAL TRANSPLANTATION

• Absolute• Active malignancy-a period of at least 2 years of complete remission

is recommended for most tumours prior to transplantation • Active vasculitis or anti-GBM disease, with positive serology-at least

1 year of remission is recommended prior to transplantation • Severe ischaemic heart disease • Severe occlusive aorto-iliac vascular disease • Relative • Age-while practice varies, transplants are not routinely offered to

very young children (< 1 year) or older people (> 75 years) • High risk of disease recurrence in the transplant kidney • Disease of the lower urinary tract-in patients with impaired bladder

function, an ileal conduit may be considered • Significant comorbidity

Page 82: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

• Once the graft begins to function, normal or near-normal biochemistry is usually achieved within a few days.

• All transplant patients require regular life-long clinic follow-up to monitor renal function and immunosuppression.

• Management after transplantation• Immunosuppressive therapy is required to prevent rejection. • Different therapeutic regimens are used; a commonly used

one is triple therapy consisting of prednisolone, plus ciclosporin or tacrolimus and azathioprine. Newer immunosuppressive drugs such as mycophenolate mofetil and rapamycin are increasing in use

• ..

Page 83: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

• Immunosuppression, which must usually be taken throughout the life of the transplant, is associated with an increased incidence of infection, particularly opportunistic infections such as cytomegalovirus and Pneumocystis carinii .

• There is also an increased risk of malignancy, especially of the skin.• Approximately 50% of white patients develop skin malignancy by 15 years

post-transplant.• Lymphomas are rare but may occur early and are often related to

infection with herpes viruses, especially Epstein.

Quality of life studies indicate that transplantation offers the best hope of complete rehabilitation and is the most cost-effective treatment for end-stage CRF.

Page 84: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Complications Post Transplant

InfectionRejectionHypertensionMalignancies (lip, skin, lymphomas, cervical)Recurrence of renal diseaseRetroperiotneal bleedArterial stenosisUrine leakage

InfectionRejectionHypertensionMalignancies (lip, skin, lymphomas, cervical)Recurrence of renal diseaseRetroperiotneal bleedArterial stenosisUrine leakage

Page 85: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Complications Post Transplant

Rejection is a major problem

Hyperacute rejection: occurs within minutes to hours after transplantation

Renal vessels thrombosis occurs and the kidney dies

There is no treatment and the transplanted kidney is removed

Rejection is a major problem

Hyperacute rejection: occurs within minutes to hours after transplantation

Renal vessels thrombosis occurs and the kidney dies

There is no treatment and the transplanted kidney is removed

Page 86: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Complications Post Transplant

Acute Rejection: occurs 4 days to 4 months after transplantation

It is not uncommon to have at least one rejection episode

Episodes are usually reversible with additional immunosuppressive therapy (Corticosteroids, ALG, or ATG)

Signs: increasing serum creatinine, elevated BUN, fever , decrease output, increasing BP, tenderness over the transplanted kidneys

Acute Rejection: occurs 4 days to 4 months after transplantation

It is not uncommon to have at least one rejection episode

Episodes are usually reversible with additional immunosuppressive therapy (Corticosteroids, ALG, or ATG)

Signs: increasing serum creatinine, elevated BUN, fever , decrease output, increasing BP, tenderness over the transplanted kidneys

Page 87: Medicine 5th year, 3rd, 4th & 5th lectures (Dr. Kawa Husain)

Complications Post Transplant

Chronic Rejection: occurs over months or years and is irreversible.

The kidney is infiltrated with large numbers of T and B cells characteristic of an ongoing , low grade immunological mediated injury

Gradual occlusion renal blood vessels

Signs: proteinuria, HTN, increase serum creatinine levels

Supportive treatment, difficult to manage

Replace on transplant list

Chronic Rejection: occurs over months or years and is irreversible.

The kidney is infiltrated with large numbers of T and B cells characteristic of an ongoing , low grade immunological mediated injury

Gradual occlusion renal blood vessels

Signs: proteinuria, HTN, increase serum creatinine levels

Supportive treatment, difficult to manage

Replace on transplant list