Study Highlights Risk of Proteinuria in Patients Receiving Immune Checkpoint Inhibitors

"Proteinuria may develop during immune checkpoint inhibitor therapy. Regular urinalysis monitoring is recommended, particularly for patients who have undergone multiple cycles of ICI treatment and those with comorbid liver cirrhosis," the researchers wrote.

Proteinuria, a condition where excess protein is found in the urine, can be an early indicator of kidney dysfunction, and its emergence during ICI therapy may signal potential renal complications. ICIs are a class of cancer therapies that enhance the body's immune system to recognize and attack cancer cells. These drugs have revolutionized cancer treatment, offering significant survival benefits for patients with various cancers, including melanoma, lung cancer, and renal cell carcinoma. However, their use is not without risk, as they can also cause immune-related adverse events, affecting various organs, including the kidneys.

Against the above background, Qiongqiong Yang, Department of Nephrology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China, and colleagues aimed to investigate the incidence of proteinuria and the factors associated with its development during immune checkpoint inhibitor therapy.

For this purpose, the researchers conducted a case-control observational study involving cancer patients treated with immune checkpoint inhibitors (ICIs). Clinical and laboratory data were collected at baseline and throughout the follow-up period. Patients who developed proteinuria during ICI treatment were classified into the proteinuria group.

The study led to the following findings:

• A total of 440 patients were included in the study between March 2019 and August 2022.
• Forty-eight patients (10.9%) developed proteinuria after receiving immune checkpoint inhibitors.
• There was no significant difference in the occurrence of acute kidney injury between the proteinuria group and the control group (2.1% versus 2.3%).
• Multivariable logistic analysis revealed that the cumulative number of ICI cycles (OR 1.079) and the presence of comorbid liver cirrhosis (OR 2.198) were independently associated with the development of proteinuria following ICI treatment.

Despite some limitations in the study, such as the lack of kidney biopsies in most proteinuric cases and the retrospective design, which may restrict the generalizability of the findings, the authors concluded that proteinuria can develop during immune checkpoint inhibitor (ICI) therapy. Therefore, regular urinalysis monitoring is essential.

"The study also identified that the cumulative number of ICI cycles and comorbid liver cirrhosis were independently associated with the occurrence of proteinuria during treatment. Further prospective studies with more comprehensive diagnostic approaches could strengthen these findings," the researchers concluded.

Reference:

Su, J., Bi, Z., Chen, P. et al. Proteinuria following administration of immune check point inhibitor: a case-control observational study. BMC Nephrol 25, 429 (2024). https://doi.org/10.1186/s12882-024-03868-5