Pediatric nephrology is a medical subspecialty dedicated to diagnosing and treating disorders of the kidneys and urinary tract in infants, children, and adolescents. This field addresses a wide range of issues, from structural abnormalities present at birth to acquired diseases that develop later in life. Kidney issues in children are often different from those in adults; for example, adult kidney failure is frequently linked to long-standing diabetes or hypertension, while pediatric kidney disease is often rooted in congenital or genetic causes.
The Core Function and Scope
The kidneys perform several functions beyond filtering waste, and pediatric nephrologists manage these processes within the context of a developing child. They focus on maintaining the body’s delicate balance of fluids and electrolytes, which is susceptible to disruption in smaller patients. Regulation of sodium, potassium, calcium, and phosphorus is a primary responsibility of the kidneys, and imbalances can impact growth and nerve function.
Managing hypertension is another significant aspect, as kidney disease commonly causes elevated blood pressure in children. The specialty also addresses the kidneys’ role in producing hormones, such as erythropoietin (for red blood cell production) and calcitriol (for bone health). Nephrologists consider the impact of kidney dysfunction on a child’s overall growth, development, and nutritional status.
Conditions Managed
Pediatric nephrologists treat a spectrum of conditions, which are often grouped based on their origin, beginning with abnormalities present from birth. Congenital anomalies of the kidney and urinary tract (CAKUT) are the most frequent cause of chronic kidney disease (CKD) in children. These structural issues include renal dysplasia, where the kidney tissue does not develop properly, and obstructive uropathies, such as posterior urethral valves, which block the flow of urine.
Acquired diseases involve conditions that appear after birth, frequently triggered by infections or autoimmune responses. Glomerulonephritis describes a group of diseases that cause inflammation in the glomeruli, the kidney’s filtering units, which can lead to blood and protein leaking into the urine. Nephrotic syndrome is characterized by heavy protein loss in the urine, resulting in widespread swelling (edema) due to low protein levels in the blood. Acute kidney injury (AKI) is a sudden drop in kidney function, sometimes caused by severe dehydration, certain medications, or conditions like hemolytic uremic syndrome (HUS).
A significant part of the practice involves managing chronic conditions that require long-term care and monitoring. Chronic kidney disease (CKD) represents the progressive and irreversible loss of kidney function over months or years, requiring careful management to slow its progression. Inherited disorders, such as autosomal recessive polycystic kidney disease (ARPKD), involve the growth of numerous cysts that progressively impair function. Kidney stone disease (nephrolithiasis) is also managed, often involving metabolic evaluations to determine the underlying cause of stone formation.
They also manage systemic diseases, such as lupus nephritis, where systemic lupus erythematosus causes inflammation and damage to the kidneys. Nephrologists work to mitigate the effects of these conditions on a child’s bone density, growth trajectory, and overall quality of life.
Specialized Treatments and Interventions
Pediatric nephrologists employ specialized diagnostic and therapeutic procedures to manage these complex conditions. A renal biopsy, where a small tissue sample is taken from the kidney for microscopic analysis, is a standard procedure used to accurately diagnose the cause of conditions like glomerulonephritis. They also prescribe specialized pharmaceutical therapies, including immunosuppressive medications to treat autoimmune kidney diseases and specific blood pressure medications designed to protect the kidneys from further damage. For children with CKD, dietary management is a major focus, often involving limiting protein, phosphorus, and potassium intake, guided by a renal dietitian.
When kidney function declines to end-stage renal disease (ESRD), renal replacement therapy (RRT) becomes necessary. Dialysis is one form of RRT, delivered as hemodialysis or peritoneal dialysis. Hemodialysis uses a machine to filter the blood outside the body, typically performed several times a week in a specialized center. Peritoneal dialysis uses the child’s abdominal lining as a natural filter and can often be performed at home, frequently during the night, offering more flexibility for younger patients and their families.
Kidney transplantation represents the preferred long-term treatment for ESRD, offering the best chance for a return to a more normal life and improved growth. The pediatric nephrology team coordinates the entire process, from pre-transplant evaluation and finding a suitable donor to the intensive post-transplant care. Long-term management involves carefully monitoring the transplanted organ, adjusting immunosuppressive drugs to prevent rejection, and addressing side effects like growth retardation, sometimes through the use of growth hormone therapy.
When to Consult
A referral to a pediatric nephrologist is recommended when a child exhibits signs of persistent kidney or urinary tract dysfunction that requires specialized investigation. One of the most common reasons for consultation is the persistent presence of protein (proteinuria) or blood (hematuria) in the urine, especially when the cause is not immediately clear or if it is associated with other symptoms. These findings, often discovered incidentally during routine urine tests, can be the first indication of a filtering problem within the kidneys.
A referral is also indicated for several key symptoms:
- Unexplained or persistent high blood pressure, as the kidneys play a primary role in blood pressure regulation.
- Significant swelling (edema), particularly around the eyes, face, or ankles, that suggests the kidneys are failing to manage fluid balance effectively.
- Recurrent urinary tract infections (UTIs), especially those associated with fever or poor growth, signaling underlying structural or functional issues.
- Failure to thrive, delayed growth, or bone problems not explained by other causes, suggesting a chronic kidney issue interfering with metabolism.