What Complications Can Hydronephrosis Cause?
Hydronephrosis, a condition characterized by the swelling of the kidney due to urine buildup, can lead to a range of health complications if left untreated. The severity and type of symptoms often depend on how quickly the condition develops and the extent of urinary blockage. While some individuals may experience mild discomfort, others can face serious, even life-threatening, consequences.
Common Symptoms of Hydronephrosis
One of the most frequently reported signs is pain, typically felt in the flank or lower back. This discomfort can vary from a dull, persistent ache to sudden, intense episodes known as renal colic—often described as one of the most severe types of pain, comparable to childbirth or a sharp knife-like sensation. These painful episodes usually occur when there's a sudden obstruction in the urinary tract, such as from kidney stones.
In addition to pain, many patients experience gastrointestinal symptoms like nausea and vomiting. These often accompany acute flare-ups and are the body's response to intense internal distress. Some individuals may also notice visible changes in their urination patterns, including decreased urine output or difficulty emptying the bladder completely.
Physical Signs and Detectable Abnormalities
In more advanced cases, hydronephrosis can cause noticeable physical changes. For instance, an enlarged kidney might be felt during a physical exam as a palpable mass in the abdomen. This swelling occurs because the kidney becomes distended with accumulated urine, leading to enlargement that healthcare providers can sometimes detect manually.
Blood in the urine, or hematuria, is another potential indicator. While not always visible to the naked eye, microscopic hematuria can be identified through lab testing. When visible, the urine may appear pink, red, or brownish, signaling possible damage to the kidney or urinary tract structures.
Risks of Infection and Systemic Illness
Urinary stasis—the inability to fully drain urine—creates an ideal environment for bacteria to grow, increasing the risk of urinary tract infections (UTIs) and, more seriously, pyelonephritis (kidney infection). Patients may develop fever, chills, and worsening flank pain. If the infection spreads into the bloodstream, it can lead to sepsis, a potentially fatal condition requiring immediate medical intervention.
Long-Term Consequences: Kidney Damage and Failure
Perhaps the most concerning outcome of chronic or severe hydronephrosis is irreversible kidney damage. Prolonged pressure from trapped urine can impair kidney function over time, reducing its ability to filter waste and regulate fluids. In extreme cases, this can progress to acute or chronic kidney failure, necessitating dialysis or even transplantation.
In the worst scenarios, untreated hydronephrosis can result in complete loss of kidney function and tissue necrosis—where parts of the kidney die due to lack of blood flow and ongoing pressure. Early diagnosis and treatment are critical to preserving kidney health and preventing long-term complications.
To reduce risks, individuals experiencing persistent back pain, changes in urination, or unexplained fever should seek prompt medical evaluation. Imaging tests like ultrasounds or CT scans are commonly used to confirm hydronephrosis and identify underlying causes such as kidney stones, tumors, or structural abnormalities.