What does left kidney hydronephrosis mean, and is it serious?

Left hydronephrosis refers to a pathological condition in which impaired urine drainage from the left kidney leads to increased intrarenal pressure, dilation of the renal pelvis and ureter, renal parenchymal atrophy, and decreased kidney function. Common causes include obstructive diseases of the upper urinary tract such as left kidney stones, left ureteral stones, left renal pelvic tumors, and left ureteral tumors. Left hydronephrosis may be accompanied by symptoms such as flank pain, abdominal mass, frequent urination, hematuria, nausea, and vomiting. The severity of left hydronephrosis depends on the degree and duration of fluid accumulation. Mild cases may present no obvious symptoms, but as the condition progresses, it can impair renal function and even lead to renal failure. Therefore, once left hydronephrosis is detected, prompt medical evaluation is essential to determine the underlying cause and initiate appropriate treatment.