Kidney cysts in HIV patients while taking medication should be judged according to the type and grade of kidney cysts. Renal cysts are categorized as simple or complex. Simple renal cysts are commonly found in normal kidneys and their incidence increases with age. These cysts are asymptomatic benign lesions and generally do not require treatment. However, complex cysts may require imaging follow-up, biopsy, or surgical resection for diagnosis. The investigators developed the Bosniak renal cyst grading system to assist in the management of simple and complex renal cysts. Renal cystic masses are categorized into 5 grades based on morphologic and enhancement features on plain and enhanced CT. 1.Bosniak Grade I and II cysts do not require further evaluation. If it is not possible to differentiate between grade II and IIF cysts, follow-up imaging is required. 2. For grade IIF cysts, it is recommended that previous results be obtained as much as possible for comparison. If previous findings cannot be obtained, an additional imaging study (e.g., contrast-enhanced MRI) is recommended to further characterize the lesion. If no clear distinction can be made between grade IIF and grade III cysts, they are treated as grade III. 3. Management of grade III and IV cysts varies depending on physician and patient factors. Options include continuous active surveillance with regular imaging, fine needle aspiration biopsy (which may require ablation), or partial nephrectomy when feasible. The approach taken usually depends on the lesion presentation as well as the patient’s comorbidities and life expectancy. In general, surgery is preferred for those who are suitable for surgery. Patients who are not suitable for surgery or who choose to be monitored will undergo CT or MRI at 6 months and CT or ultrasound once a year thereafter.