Can a renal cyst cause back pain?

From the Guidelines

Yes, a renal cyst can cause back pain, particularly when the cyst grows large enough to stretch the kidney capsule or press on surrounding structures, as suggested by the KDIGO 2025 clinical practice guideline for the evaluation, management, and treatment of autosomal dominant polycystic kidney disease (ADPKD) 1.

Key Points to Consider

• The pain typically occurs in the back, side, or upper abdomen and can worsen after prolonged periods of sitting or standing.
• Simple renal cysts often don't require treatment unless they cause symptoms or complications.
• If symptoms persist, healthcare providers may recommend pain relievers like acetaminophen or ibuprofen for temporary relief.
• Imaging tests such as ultrasound or CT scan may be suggested to evaluate the cyst.
• In cases where pain is severe or persistent, procedures to drain or remove the cyst might be considered, with options like spinal-cord stimulation providing significant pain relief in specific cases of moderate-to-severe refractory mechanical or visceral pain, as noted in the KDIGO guideline 1.

Clinical Approach

When evaluating back pain potentially caused by a renal cyst, it's essential to consider the size of the cyst and its impact on the kidney and surrounding structures.

• Longitudinal eGFR slope can aid in identifying pain caused by cyst enlargement, as indicated by the KDIGO 2025 guideline 1.
• Nephrectomy is typically reserved for severe intractable pain, usually with advanced kidney disease or after other treatments have failed.
• A thorough clinical assessment, including imaging studies, is crucial for determining the appropriate management strategy for renal cyst-related back pain.

From the Research

Renal Cysts and Back Pain

• Renal cysts are commonly encountered in clinical practice and can cause various symptoms, including pain 2, 3.
• Although most cysts are benign, some can cause pain, collecting system compression, hematuria, hypertension, and secondary infection 3.
• A study reported a case of a 70-year-old man with lower back pain who was found to have large renal cysts on bone scintigraphy, which were confirmed on CT images 4.
• The patient's symptoms improved after laparoscopic unroofing of the renal cysts, suggesting that back pain can be caused by urinary disorders, including renal cysts 4.
• The diagnosis and management of complex renal cysts can be challenging, and the ability to differentiate between benign and malignant cysts is crucial 5.

Symptoms and Diagnosis

• Renal cysts can cause a range of symptoms, including back pain, collecting system compression, and hematuria 3, 4.
• The diagnosis of renal cysts typically involves imaging studies, such as CT or ultrasound, and the Bosniak classification system is used to categorize the complexity of the cysts 5.
• In some cases, percutaneous biopsy may be necessary to determine the nature of the cyst 5.

Treatment and Management

• The treatment of renal cysts depends on the size, location, and complexity of the cyst, as well as the presence of symptoms 3, 5.
• Laparoscopic unroofing of renal cysts can be an effective treatment option for symptomatic patients 4.
• Physicians should be aware of the potential adverse renal effects of certain medications, such as acetaminophen, which has been associated with an increased risk of renal impairment 6.