Why did the kidney cyst disappear after one year?

In general, the disappearance of a renal cyst after one year may be related to natural regression of congenital renal cysts, spontaneous absorption of the cyst, drainage of cystic fluid, self-healing of renal tubular diverticula after infection, or infectious cystic nephritis. If discomfort symptoms occur, it is recommended to seek medical attention promptly and receive symptomatic treatment under the guidance of a qualified physician. Specific analyses are as follows:

1. Natural Regression of Congenital Renal Cysts

Congenital renal cysts are fluid-filled sac-like structures formed during kidney development. These cysts may gradually shrink or even disappear over time due to changes in internal pressure, fluid absorption, or natural atrophy of the cyst wall. In such cases, special treatment is usually unnecessary; regular monitoring is sufficient.

2. Spontaneous Absorption of Cysts

In asymptomatic cases with cysts smaller than 3 cm in diameter, some renal cysts may resolve spontaneously, with gradual atrophy of the cyst wall leading to disappearance of the cyst. Typically, there are no obvious accompanying symptoms. Maintaining healthy lifestyle habits, including a balanced diet and moderate exercise, is recommended.

3. Drainage of Cystic Fluid

When the internal pressure within a cyst exceeds a certain level, the fluid may be expelled from the body through the kidney's excretory system, resulting in cyst shrinkage or disappearance. This condition generally does not require specific treatment, but patients should undergo regular follow-up examinations to ensure the cyst does not recur or lead to other complications.

4. Self-Healing of Renal Tubular Diverticula After Infection

Renal tubular diverticula refer to localized weak areas in the renal tubule wall caused by urinary tract infections or other factors. Once the infection is controlled, the diverticula may naturally shrink or disappear as inflammatory reactions subside. Patients may experience symptoms such as frequent urination, urgency, and dysuria. It is recommended to follow medical advice and use medications such as amoxicillin capsules, levofloxacin tablets, or ceftriaxone sodium for injection.

5. Infectious Cystic Nephritis

This condition involves an inflammatory response in the kidneys caused by bacteria, fungi, or other pathogens, leading to local tissue necrosis and cystic expansion. Once the immune system successfully eliminates the pathogen, the cystic lesions may shrink or resolve. Common symptoms include fever, flank pain, and hematuria. Patients should follow medical instructions and take medications such as captopril tablets, irbesartan tablets, or Jinshuibao capsules.

During recovery, a low-protein, low-sodium, and low-fat diet is recommended, along with adequate sleep and avoidance of heavy physical labor, all of which help maintain kidney health.