Chronic Kidney Diseases In Children

Introduction:

Chronic kidney disease has been an emerging medical condition in children in the past 20 years. In chronic kidney disease, the kidneys are permanently damaged. It can affect the health of the child in many ways and can also be a life-threatening condition. This may eventually lead to kidney failure. There are several factors that contribute to kidney diseases. In chronic kidney disease, there is an underdevelopment of the kidneys and urinary tract, and this is the most common cause of chronic kidney disease in pediatric patients. It may cause discomfort in children during urination. These children are highly susceptible to urinary tract infections.

What Is the Role of Kidneys in the Human Body?

• They are essential for overall health. Their main work is filtration and excretion of water and other waste from the blood.

• They play a vital role in salt and mineral balance, such as sodium and potassium, and produce hormones for maintaining blood pressure.

• They are involved in red blood cell production, thus helping in preventing anemia through the mechanism of erythropoiesis. They produce mature, hemoglobin-rich red blood cells and also carry oxygen to the tissues.

• They filter about 120 to 150 quarts of blood every day and produce 1 to 2 quarts of urine that are expelled from the body.

What Are the Types of Renal Disease?

Renal diseases are categorized into two main types depending on the onset of the disease. They are:

1. Acute Renal Diseases: They have an abrupt onset of the disease condition, and they are mostly reversible.

2. Chronic Renal Disease: They take several months to present the disease symptoms. They are irreversible and can also be life-threatening.

What Are the Causes of Chronic Kidney Diseases in Children?

The most common causes in children are:

• Birth defects.

• Presence of hereditary disorders.

• Infections.

• Trauma.

• Obstruction of the urinary tract.

• Presence of any systemic disease.

• Birth Defects: They are caused due to any disturbances during growth and development that affects the kidneys in the intrauterine stage. It causes developmental disorders of the kidneys, such as:

• Renal Agenesis: Only one kidney is present.

• Renal Dysplasia: Both kidneys are present, but they are non-functional.

• Ectopic Kidneys: The kidneys are present in some other location.

• Hereditary Conditions: They are inherited from their parents.

• Polycystic Kidney Disease: In this condition, the kidney has several fluid-filled cysts that destroy the tissues of the kidney and affect their functions.

• Alport Syndrome: This is a genetic condition due to a gene mutation that affects the production of collagen that forms the glomeruli, which are the filtering apparatus of the kidneys.

• Infections:

• Hemolytic Uremic Syndrome: This is a bacterial infection caused due to the bacteria Escherichia coli (E. coli). It may cause kidney failure in some children.

• Post-Streptococcal Glomerulonephritis: This is seen after any skin or throat infections. It does not directly cause kidney dysfunction, but it triggers the immune system and produces antibodies that destroy the kidneys.

• Nephrotic Syndrome: They are a group of symptoms denoting kidney damage. The conditions included in nephrotic syndrome are:

• Albuminuria: The presence of too much albumin in the urine.

• Hyperlipidemia: Elevated levels of cholesterol in the blood.

• Edema: Swelling caused due to excess fluid trapped within the body tissues.

• Hypoalbuminemia: Reduced albumin levels in the body that causes fluid retention.

• Systemic Diseases:

• Lupus Nephritis: It is an autoimmune condition that produces autoantibodies affecting the kidneys.

• Diabetic Kidneys: Kidney disease due to diabetes. It is not commonly seen in children but common in adults.

• Trauma: There are several traumatic conditions that cause damage to the kidneys and alter their function, such as burns, dehydration, injuries, etc.

What Are the Symptoms of Chronic Kidney Disease in Children?

About 80 % of children with chronic kidney diseases are often asymptomatic. Symptoms appear only during the end stages. The common presentation includes:

• Fatigue and lethargy.

• Inability to focus on things and mental distractions.

• Restless leg syndrome and insomnia.

• Fever and weight loss due to poor appetite.

• Swelling of the eyes and feet also known as edema.

• Frequent urination, especially during the nighttime.

• Frequent bedwetting is seen in children above five years of age.

• Severe headaches due to increased blood pressure.

What Are the Possible Complications?

• Children may develop high blood pressure.

• Anemia is due to the low production of red blood cells.

• Growth failure and malnourishment.

What Is the Glomerular Filtration Rate?

The glomerular filtration rate (GFR) shows how well the kidneys are functioning and filtering the waste from the blood. The GFR varies in men and women and also depends on the person’s age.

• In Males: 100 to 130 ml/min.

• In Females: 90 to 120ml/min.

What Are the Stages of Kidney Disease?

Chronic kidney diseases in children are divided into five stages depending on the glomerular filtration rate (GFR) and the efficiency of the kidney in blood filtration. These include.

• Stage 1: Kidney damage with a normal glomerular filtration rate of more than 90.

• Stage 2: Kidney damage with mild reduction of GFR (60 - 89).

• Stage 3: GFR moderately reduced (30 - 59).

• Stage 4: Severely reduced GFR (15 - 29)

• Stage 5: Renal failure.

How Is Chronic Kidney Disease Diagnosed?

Chronic kidney disease in children is diagnosed by a physical examination and a medical history. The clinician looks for the signs and symptoms encountered in the child. If chronic kidney disease is suspected, then several diagnostic tests may be required to confirm the diagnosis.

Laboratory Tests:

• Dipstick Test for Albumin: This test detects the presence of albumin content in the urine. Generally, albumin in the urine indicates kidney damage.

• Albumin Creatinine Ratio: This is more accurate than the dip test. Here, the ratio of albumin and creatine are measures that denote the extent of kidney damage in the affected children.

• Blood Tests: The blood test helps to determine the filtering capacity of the kidney. The ability of the kidneys to filter blood per minute is measured by blood tests.

Imaging Tests:

• Kidney Biopsy: A small sample of the kidney tissue is taken, and a microscopic examination is done. This shows any tissue damage or abnormalities that are seen in the kidney, and the cause of kidney damage can be assessed.

• Kidney Ultrasound: They use sound waves to examine the kidney, detect the damage to the organ and evaluate any obstruction present in the urinary tracts

• Voiding Cystourethrogram: It is another imaging test that uses a small flexible tube and is inserted into the urethra of the child. The urethra is a tube that connects the urinary bladder and the kidneys. A contrast medium is injected into the bladder, and an X-ray is taken. This contrast medium shows the areas of abnormalities.

How Is Chronic Kidney Disease Managed?

The treatment of chronic kidney disease varies in each individual according to the cause and depending on the stage of the disease. For mild to moderate chronic kidney disease (stage 1 to stage 3), the children are often asymptomatic, but kidney dysfunction is seen. This causes several other complications.

The goals of the treatment plan are as follows:

• To identify the condition that causes chronic kidney diseases.

• To manage the symptoms and provide relief to the child.

• Proper dietary and lifestyle modifications to control the progression of the disease.

• Kidney transplantation and dialysis are recommended for end-stage renal diseases.

1. Acidosis: Kidney dysfunction results in the imbalance of the acid-base levels and results in a condition called acidosis. So they are treated by oral therapy with bicarbonates. This cures the acidosis condition.

2. Anti-Hypertensive Therapy: Children with chronic kidney disease will have elevated blood pressure levels. So medications such as angiotensin-converting enzyme inhibitors and angiotensin receptor blockers are prescribed. They relax the blood vessels and make the pumping action of the heart more efficient.

3. Diuretics: They help to increase urine output in children.

4. Anemia: Another major complication encountered in children with chronic kidney disease is anemia. They are treated by supplementing the erythropoietin hormone. They stimulate the bone marrow, where the red blood cells are produced.

5. Dietary Modifications: Changes in the diet are done to treat loss of appetite. Along with dietary modifications, other lifestyle changes and growth hormone supplementation are also introduced.

6. Growth Hormone Therapy: As growth is impaired in the affected children, growth hormone therapy is initiated. The growth hormones are recommended daily, and the parents can inject their children with the hormone.

7. Treatment of Birth Defects: Defects such as renal agenesis and dysplasia generally require no treatment unless there is any discomfort to the child in voiding urine. If there is any kidney damage that interferes with the function, then surgery may be an option.

8. Polycystic Kidneys: These children are highly susceptible to urinary tract infections. Hence antibiotic therapy is given to fight bacterial infections.

In patients with end-stage renal diseases, kidney transplantation is the only option.

1. Kidney Transplantation: This is the final option for end-stage renal diseases. This improves the quality of life and increases the life expectancy of the child. Generally, for kidney transplantation, siblings or family members with two healthily functioning kidneys are chosen as donors. The family members are preferred as they have the same human leukocyte antigen. This prevents the rejection of the transplanted new organ. Soon after the surgery, the child is prescribed immunosuppressive medications to prevent organ rejection.

2. Hemodialysis: In some cases, if there is no proper donor available for kidney transplantation, then an alternate procedure called dialysis is recommended. In dialysis, a machine is used to purify the blood of the child. In end-stage renal disease, dialysis is recommended three to four times a week. This procedure is continued until a suitable donor is available for kidney transplantation.

Conclusion:

Although chronic kidney disease is a severe health condition that affects the growth of the child, appropriate treatment can improve their quality of life and extend their life expectancy. It not only creates stress for the child but also for the parents. With dietary modifications and lifestyle changes, the progression of the disease can be controlled in mild and moderate cases. Surgery is recommended only for end-stage disease, and regular follow-ups may be required.