Typically, a healthy adult kidney weighs approximately 100-150 grams. However, Zhang, a patient treated in Hangzhou, had a right kidney as large as a basketball—ten times the size of his left kidney.
The urology department's associate chief physician explained that in healthy adults, kidneys typically shrink gradually with age. Zhang Xiaozhang's right kidney had a severely narrowed connection to the ureter. Urine produced in the kidney couldn't pass through the constricted outlet, leading to increasingly severe hydronephrosis. Acute hydronephrosis often causes intense lower back pain and a sensation of fullness, while chronic cases may only present with a feeling of fullness or even no symptoms at all.
Clinically, causes of hydronephrosis include:
1. Ureteral twists, adhesions, bands, or valve-like structures—congenital or acquired—commonly occurring at the ureteropelvic junction or lumbar ureter segment, affecting nearly two-thirds of children and infants.
2. Segmental dysfunction: Due to segmental muscle absence, hypoplasia, or anatomical disruption at the ureteropelvic junction or upper ureter, normal peristalsis is impaired, causing dynamic obstruction.When this defect occurs at the ureterovesical junction, it results in congenital megaureter, leading to renal and ureteral dilatation and hydronephrosis.
3. Vascular compression accounts for approximately one-third of cases, primarily due to ectopic renal portal vessels located anterior to the pyeloureteric junction. Other causes include horseshoe kidney and impaired renal rotation during embryonic development.
Lifestyle Habits Associated with Hydronephrosis
1. Chronic Urine Retention
Holding urine obstructs drainage from the renal pelvis, predisposing to hydronephrosis.
2. Frequent Overtime Work and Late Nights
Excessive fatigue weakens immunity. Prolonged overtime reduces physical activity, increasing renal strain.
3. Skipping breakfast
Chronic breakfast omission not only triggers hydronephrosis but also predisposes to other diseases.
Clinical manifestations of hydronephrosis
Patients often remain asymptomatic for extended periods, only noticing when an abdominal mass or lumbar distension develops. The mass is usually discovered incidentally and typically presents with a cystic sensation. Pain is generally mild or even absent.
However, in cases of intermittent hydronephrosis (caused by vascular compression or renal ptosis), renal colic may occur. This presents as severe pain radiating along the costal margin and ureteral course, often accompanied by nausea, vomiting, abdominal distension, and oliguria. Symptoms typically resolve within minutes to hours, followed by copious urine output.Examination may reveal an enlarged kidney. In cases of massive hydronephrosis, the tension may not be particularly high.
If infection complicates hydronephrosis, pyuria and systemic toxic symptoms such as chills, fever, headache, and gastrointestinal dysfunction may occur. Some patients present with urinary tract infection as the initial symptom. For patients unresponsive to urinary tract infection treatment, the presence of an obstruction must be considered.In severe obstruction, inflammatory exudate cannot be excreted via urine, resulting in urine without white blood cells. However, local pain and tenderness are more pronounced in such cases. An enlarged hydronephrotic kidney is more susceptible to trauma; even minor injury may cause rupture and bleeding. Urine entering the retroperitoneal space or peritoneal cavity triggers severe reactions, including pain, tenderness, and systemic symptoms.
How should patients with hydronephrosis manage daily care?
1. Dietary Management
Maintain a healthy dietary structure, avoiding excessive protein intake to prevent overburdening the kidneys and hindering recovery. Patients with unilateral hydronephrosis need not restrict fluid intake, whereas those with renal impairment should limit daily water consumption.
2. Medication Management
Daily medication is essential, particularly before urinary obstruction resolves. To prevent infection and protect renal function, antibacterial drugs like erythromycin may be used under medical supervision. Traditional Chinese medicine can also be employed for its heat-clearing and toxin-eliminating effects.