Kidney failure in children is a serious condition where kidneys can no longer properly filter waste from the blood. These two bean-shaped organs, located just below the rib cage, remove waste products and excess fluid from the body, balancing water, salts, and minerals. This article explores the causes of kidney failure in children, from congenital conditions to those that develop over time or arise suddenly.
Understanding Pediatric Kidney Failure
Kidney failure occurs when the kidneys lose their ability to filter waste from the blood. This condition can manifest in two forms: Acute Kidney Injury (AKI) and Chronic Kidney Disease (CKD). AKI involves a sudden, often temporary, loss of kidney function, developing over hours or days. While AKI can be severe and often requires hospitalization, it is treatable, and kidneys may recover.
Chronic Kidney Disease (CKD) represents a progressive, long-term decline in kidney function that worsens slowly over at least three months. CKD signifies kidney damage preventing them from performing their filtering and balancing roles. Both AKI and CKD can lead to kidney failure in children, where kidney function is severely impaired, requiring dialysis or a transplant. An episode of AKI can also increase the risk of developing CKD later in life.
Causes Present at Birth
Kidney failure in children can stem from congenital (present at birth) or genetic (inherited) conditions. A major category is Congenital Anomalies of the Kidney and Urinary Tract (CAKUT). These are structural issues affecting kidney or urinary tract formation and function. Examples include kidney agenesis (failure to develop) or kidney dysplasia (abnormal development and function).
Hydronephrosis, another CAKUT condition, can result from blockages like posterior urethral valves (PUV). PUV are tissue flaps in the urethra that obstruct urine flow, causing urine backup and potential kidney damage.
Beyond structural anomalies, inherited genetic disorders can impair kidney function from birth or early childhood. Polycystic Kidney Disease (PKD) is one such disorder, characterized by numerous fluid-filled cysts within the kidneys, interfering with filtration.
Other genetic conditions include Alport Syndrome (progressive kidney damage) and Nephropathic Cystinosis (amino acid cystine accumulation in kidney cells, causing dysfunction). These conditions can lead to a gradual decline in kidney function, often progressing to CKD.
Causes Developing Over Time
Beyond congenital conditions, kidney failure in children can arise from acquired conditions that gradually diminish kidney function, often leading to CKD. Autoimmune diseases are a group where the immune system attacks the kidneys. Lupus Nephritis, for instance, is kidney inflammation caused by systemic lupus erythematosus. Henoch-Schönlein Purpura Nephritis is another autoimmune condition that can damage kidney filters.
Primary glomerular diseases, affecting the tiny filtering units (glomeruli) within the kidneys, also contribute to kidney function decline. Focal Segmental Glomerulosclerosis (FSGS) causes scarring in these filters, leading to protein leakage and impaired function. IgA Nephropathy involves immune deposits in the glomeruli, causing inflammation. Minimal Change Disease can sometimes progress to kidney failure despite being manageable. These acquired conditions can slowly damage the kidneys over months or years, ultimately resulting in CKD.
Acute and Sudden Causes
Acute Kidney Injury (AKI) in children can result from factors causing a rapid loss of kidney function. Severe infections are a significant cause, such as Hemolytic Uremic Syndrome (HUS), often triggered by certain E. coli strains. HUS destroys red blood cells, blocking the kidney’s filtering system and leading to sudden damage. Severe dehydration or shock is another common trigger, drastically reducing blood flow to the kidneys and depriving them of oxygen.
Certain nephrotoxic medications can also cause acute kidney damage. Examples include some antibiotics or non-steroidal anti-inflammatory drugs (NSAIDs), especially if a child is dehydrated. Exposure to toxins like antifreeze can severely harm kidney cells. Severe trauma, like a major injury or surgery, can lead to substantial blood loss or a sudden drop in blood pressure, impacting kidney blood flow and causing AKI. These acute causes often require immediate medical attention, and prompt treatment can sometimes reverse the damage.