Complications of Acute Glomerulonephritis in Children: What Parents Need to Know

Acute glomerulonephritis (AGN) is a sudden inflammation of the glomeruli—the tiny filtering units in the kidneys—commonly affecting children following infections such as strep throat or skin infections. While many cases resolve with proper treatment, some children may develop serious complications that require immediate medical attention. Understanding these potential risks can help parents and caregivers respond quickly and support better health outcomes.

1. Severe Fluid Overload and Circulatory Congestion

One of the most common complications of acute glomerulonephritis in children is circulatory congestion caused by fluid and sodium retention. As kidney function declines temporarily, the body struggles to eliminate excess fluid, leading to volume overload. This condition mimics congestive heart failure and can present with alarming symptoms.

Key signs include rapid breathing, shortness of breath, crackling sounds in the lungs (rales), frothy or bubbly sputum, elevated heart rate, and visible swelling (edema). In more severe cases, children may experience hepatomegaly (enlarged liver) due to venous congestion and significantly reduced urine output (oliguria). Early detection and management with diuretics and fluid restriction are crucial to prevent respiratory distress or cardiac strain.

2. Hypertensive Encephalopathy: A Neurological Emergency

High blood pressure is a frequent finding in pediatric AGN, and when it escalates rapidly, it can lead to hypertensive encephalopathy—a dangerous neurological complication. This occurs when elevated blood pressure overwhelms the brain's autoregulatory mechanisms, causing cerebral edema and impaired function.

Symptoms to Watch For

Children may exhibit persistent headaches, nausea, and vomiting. In advanced stages, they might suffer seizures, altered mental status, temporary vision loss, or even fall into a coma. These neurological manifestations require urgent evaluation and aggressive blood pressure control to prevent permanent brain injury. Medications like intravenous labetalol or nicardipine are often used in hospital settings to safely lower blood pressure.

3. Acute Kidney Injury and Potential for Renal Failure

In severe cases of glomerulonephritis, kidney function can deteriorate to the point of acute renal failure. This happens when the glomerular filtration rate drops dramatically, resulting in the buildup of waste products such as blood urea nitrogen (BUN) and creatinine in the bloodstream.

Symptoms include little or no urine production, fatigue, confusion, swelling in the legs and face, and electrolyte imbalances. If kidney function does not recover promptly, temporary dialysis may be necessary to stabilize the child, remove toxins, and maintain fluid and electrolyte balance. Most children regain kidney function over time, but close monitoring is essential during recovery.

Prevention and Proactive Care

Early diagnosis and prompt treatment of underlying infections—especially group A streptococcal infections—are key to reducing the risk of developing acute glomerulonephritis. Parents should seek medical care if their child shows signs of dark urine, facial swelling, or unexplained fatigue after an illness.

With appropriate medical intervention, the majority of children make a full recovery. However, awareness of potential complications empowers families to act swiftly and supports optimal long-term outcomes.