Many renal (kidney) diseases have no symptom or sign. Renal failure impairs the normal function of the other organs of the body. It may progress to end-stage renal failure, which is fatal if not supported with dialysis treatment or kidney transplant. Currently, there are more than 10,000 patients with end-stage renal failure in Hong Kong on dialysis treatment or with a kidney transplant.
What is Chronic Renal Failure？
The main functions of kidneys are to remove the wastes products from metabolism and regulate water, electrolyte, acid base and blood pressure in the body, produce erythropoietin (a hormone needed for producing red blood cells) and help to produce vitamin D. With progressive impairment of the renal function, there is accumulation of waste products and body fluid inside the body, causing impairment of the body function - a state known as Chronic Renal Failure.
Chronic Renal Failure can be divided into the following stages:
- Impaired renal function: 51% - 80% of normal kidney function
- Renal failure: only 25% - 50% of kidney function
- Severe renal failure: only 15% - 25% of kidney function
- End-stage renal failure: less than 10-15% of kidney function
When reaching end-stage renal failure, a patient will need some form of dialysis treatment or a kidney transplant to survive, otherwise may die.
Who are more susceptible to Chronic Renal Failure？
Patients suffering from the following diseases are more susceptible to chronic renal failure:
- Diabetes Mellitus
- Glomerulonephritis (a condition where the small structures inside the kidneys, known as glomeruli, become inflammed), including lupus nephritis (inflammation of the Renal caused by Systemic Lupus Erythematosus (SLE), a disease of the immune system)
- Family history of kidney disease (hereditary kidney disease)
How to prevent Chronic Renal Failure？
Some suggestions to prevent or to reduce the progression of kidney failure:
- Drink adequate water to keep good urine output (can help prevent kidney stone and urinary tract infection).
- Attention to personal hygiene to prevent urinary tract infection. Female and children are more susceptible to urinary tract infection (short urethra).
- Appropriate diet control - avoid the intake of excessive salt and meat, avoid the intake of high calcium and oxalate food for patient with kidney stone.
- Do not abuse drugs, e.g. painkiller for rheumatism and antibiotics.
- Prevent complications from underlying diseases, e.g. diabetes mellitus, hypertension, etc. Blood sugar and blood pressure should be controlled properly.
- Remove the cause of urinary tract obstruction, e.g. remove kidney stones and try to correct the underlying cause.
- Regular body check up, including testing the urine can discover kidney diseases in the early stage. If the patient has hematuria (blood in urine) or albuminuria (albumin in urine), he/she should undergo investigation as soon as possible.
- To receive treatment for kidney diseases, e.g. nephritis as soon as possible.
What are the causes of Chronic Renal Failure？
The cause of new case of end-stage chronic renal failure in Hong Kong in 2016 are:
- Diabetes Mellitus 49%
- Glomerulonephritis 22%
- Hypertension 11%
- Unknown reason 9%
- Others 3%
- Genetic (e.g. polycystic Renal disease, a disorder in which clusters of cysts develop primarily within the kidneys) 3%
- Urinary tract infection 3%
(Source from: Hong Kong Hospital Authority Renal Registry - Causes of new Cases of End-stage Renal Failure 2016)
Can symptoms of Chronic Renal Failure be recognized easily？
The symptoms of kidney disease and chronic renal failure are not obvious during the early stage. They can include：
- Blood in urine / tea or dark color urine (hematuria)
- Frothy urine (albuminuria)
- Turbid urine (urinary infection)
- Pain on passing urine
- Difficulties in urination (not smooth in passing urine)
- Sand / stone in the urine
- Significant increase or decrease urine output, nocturia (have to pass urine frequently during the night)
- Loin / abdomen pain
- Swelling of ankles or eyelid, puffy face
When the kidney function deteriorates to the stage of severe renal failure (less than 25% of the normal function), there may be symptoms of uraemia:
- Frequent passing of urine at night, decreased urine output
- Loss of appetite, nausea, vomiting
- Fatigue, pale looking (anemia)
- Itchy skin
- Shortness of breath
- Edema (swelling ankle or eyelid)
- Drowsy, unconscious, convulsions, coma
How to investigate and make diagnosis for Chronic Renal Failure?
Those who have suspected symptoms should consult a family doctor. Since the symptoms of kidney disease and chronic renal failure are not obvious, a patient may need to undergoing various tests including:
- Urine test: to see if there is red blood cell, white blood cell and protein
- Blood test for kidney function:
‧ Blood: urea, creatinine, protein and albumin level
‧ 24 hours urine for creatinine concentration, protein
- X rays, scanning test:
‧ Ultrasound scan (which can show the shape and structure of kidney to detect whether any obstruction)
‧ intravenous pyelogram (a radiological procedure for detecting abnormalities in the urinary system)
- Renal biopsy: using needle to take a small sample of kidney tissue under local anesthesia and examine the tissue under microscope. This can diagnosis inflammation of the kidney.
What are the treatments for Chronic Renal Failure？
Chronic renal failure cannot be cured, thus the goal of treatment is to slow down the progress of failure, reduce complications and control the symptoms. It is most important to control the underlying diseases, e.g. diabetes mellitus, hypertension, nephritis, etc. Patient should have regular follow-up; to strictly follow the medical advice with respect to diet, exercise and medications to control the condition.
It is important for patients with chronic renal failure to follow appropriate diet control. Appropriately reduce the intake of protein can help to slow down the progress of renal failure. Patient should also limit the intake of potassium, phosphorus, sodium and water and control the cholesterol level.
Common medications include:
- Drugs to control blood pressure: e.g. Angiotensin-converting enzyme (ACE) inhibitors) or Angiotensin II receptor blockers to protect kidney function.
- Erythropoietin to promote the formation of red blood cells.
- Vitamin D to support bone metabolism.
- Phosphate binder to lower the Phosphorus concentration in blood.
Renal replacement treatment
A patient cannot remove the accumulated waste products and excess water in the body when reaching end-stage of renal failure (only 10% to 15% capacity of kidney function left). Some form of kidney replacement treatment is required to survive, otherwise it may be fatal.
Kidney replacement treatments include：
Dialysis: currently, hemodialysis and peritoneal dialysis are the two main kinds of dialysis treatment.
Hemodialysis - known as "cleansing of blood", is making use of a dialyser (artificial kidney) to remove excess water, electrolytes and the waste products from the blood. Blood is taken off the patient's body via a vascular access such as arteriovenous fistula (a connection made between an artery and a vein at the forearm) or a venous catheter inserted into a main blood vessel in the neck. The blood is circulated by a dialysis machine at around 200cc/min, passing through the artificial kidney to filter off the waste products and the excess fluid. The "cleansed" blood is then return to the patient. A patient may need 2 to 3 haemodialysis treatment per week and each treatment takes 4 to 6 hours. Hemodialysis can be performed at a dialysis centre or at home (in the evening) for those who are able to do so.
Advantages: quick, effective, only 2 to 3 treatments per week, an intermittent therapy.
Disadvantages: needs to go to dialysis center for the treatment, the treatment is only intermittently and is costly.
Centers where Hemodialysis services are provided:
- Renal Units of the Hospital Authority (for those who are not suitable for peritoneal dialysis)
- "Nocturnal haemodialysis at home support program" provided by the Hospital Authority together with Hong Kong Kidney Foundation Limited
- Haemodialysis centers organized by charitable organizations
- Haemodialysis centers of private hospital
ii) Peritoneal dialysis
Peritoneal dialysis - known as "cleansing the abdomen" is making use of the blood vessel on the peritoneum (a thin membrane that lines the inside of the abdomen and surrounds and supports the abdominal organs) which allows a dialysis process.
A peritoneal dialysis catheter is implanted into the patient's abdomen as a channel where the dialysis fluid can pass in and out. The infused dialysis fluid allow waste product to be diffused out from the body into the dialysis fluid and to remove the excess water from the body.
Peritoneal dialysis is performed at home and can be continuous or intermittent:
- Continuous Ambulatory Peritoneal Dialysis - CAPD
About 90% of patients in Hong Kong is making use of this method.
The dialysis treatment (exchange of the dialysis fluid) is performed at home. The dialysis fluid is instilled into the abdomen through an implanted catheter and the dialysis fluid is allowed to dwell inside the abdomen for 4 to 10 hours. During this time, the waste products diffuse into dialysis fluid. The dialysis fluid is then drained out from the body (with the waste product) after 4-10 hours and a new bag of dialysis fluid is then instilled into the abdomen again. This process is repeated 3-4 times per day.
Advantages: removing waste product and excess water continuously, less burden on the heart and the patient can have normal activity during the dialysis process.
Disadvantages: risk of peritonitis (inflammation of the peritoneum) from the fluid exchange, but this complication is low if the dialysis process is performed carefully.
- Automated Peritoneal Dialysis
The dialysis treatment is performed during sleep overnight by connecting up to an automated peritoneal dialysis machine before going to bed every night. The machine will automatically exchange the dialysis fluid every hour or so through out the night (for 10 to 12 hours).
The advantages of peritoneal dialysis are that the patient can take care of himself/herself and the levels of toxin and water remain stable. Patient can maintain relatively normal social life and even work. There is an infection risk but this is low if the dialysis process is carried out carefully.
iii) Kidney transplant
It is a surgical transplant of a kidney from a donor to renal failure patient. The donor kidney could be from a dead (brain-stem dead) person or donated from a living person (family member). In 2016, 78 people underwent kidney transplant in Hong Kong (60 people with Renal from the dead and 18 people with kidney from living donors). There are about 2000 patients waiting for kidney transplant.
Kidney transplant is very successful:
Survival rate of patient in 1 year and 5 years: Kidney transplant from dead person- 95% and 89%; kidney transplant from living donors - 96% and 95%
Survival rate of kidney transplant in 1year and 5 years: Kidney transplant from dead body - 92% and 84%; kidney transplant from living donors - 94% and 89%
Kidney transplant surgery can cause complications, of which the most concerned one is "rejection". Patient has to take various medicines and be attentive to various nursing skills.
What are the complications of Chronic Renal Failure?
Chronic renal failure affects almost every part of the body. The main complications include：
- Cardiovascular disease
- Bone disease and fracture
How to take care of Chronic Renal Failure patients?
- Understand the condition and method of treatment
- Control the kidney disease by following the medical advice - including treatment and self-care skills, e.g. diet therapy, medications and dialysis, etc.
- Regular follow-up to monitor the progress of the disease.