For Unknown Causes of Kidney Disease, Genetic Testing Holds Promise

For 2 years, Kevin Mott’s doctors couldn’t figure out why his blood pressure medications weren’t working. They assumed that diet and lifestyle factors were the underlying cause of his hypertension. Eventually, after seeing many healthcare practitioners, Kevin was diagnosed with a rare kidney disease called focal segmental glomerulosclerosis. Once he reached kidney failure, a friend donated a kidney and he underwent lifesaving transplant surgery.

LaVarne Burton
President, CEO
American Kidney Fund

Silas Norman, MD, MPH, Board Chair, American Kidney Fund, Co-Medical Director, Kidney and Pancreas Transplantation, University of Michigan

_{Images courtesy of AKF}

After receiving his transplant, he took a DNA test and learned that he had a genetic condition known as APOL1-mediated kidney disease. Recent studies have uncovered that a genetic variation or mutation in the APOL-1 genes, which can be present among people of African and Caribbean descent, may be linked to an increased risk of kidney disease among this population.

Looking back, Kevin believes that if genetic testing was an earlier part his kidney health journey, his healthcare team could have managed his condition more appropriately.

Missed opportunities

Kevin is not alone in being unaware of the underlying cause of his kidney disease. While kidney failure is most often caused by diabetes and/or hypertension, a recent American Kidney Fund survey¹ of 300 clinicians in primary care, nephrology and endocrinology found that an estimated 15% of their patients had kidney disease with no known cause. This can have dire consequences, such as delayed treatment or inadequate disease management. It can also lead to additional comorbidities and even the loss of a transplanted kidney due to an undiagnosed rare disease that could be attacking the new kidney.

In many of these cases of kidney disease with unknown cause, there could be a genetic reason, like there was for Kevin, which can have critical implications. A recent study in the journal Nature² points to the impact that genetic testing in kidney disease could have in improving early identification of certain genes or gene variants that may increase a person's risk for kidney disease. This early detection could help drive earlier interventions and targeted therapies, and potentially prevent or slow kidney disease progression. Having an improved understanding of one’s underlying genetic condition also presents an opportunity to participate in clinical trials, manage any disease-specific comorbidities, and help improve the health outcomes of one’s family members if they also are at risk for developing kidney disease.

Genetic testing and other diagnostics, such as kidney imaging, hold significant promise to improve the accuracy and earlier detection of a kidney disease diagnosis—but there are systemic barriers we must tackle to make this promise a reality for more Americans.

One of the primary barriers is cost. There is insufficient public and private insurance coverage for genetic testing. We need more widespread and equitable coverage, not only for genetic testing, but also for access to a genetic counselor. The ability to speak with a genetic counselor is a vital step in the process because these specialists are trained to appropriately interpret test results, understand which mutations or variants are pathogenic in driving disease, help guide therapy and medical decision-making, and to counsel patients on psychosocial issues about what their results mean to them and to their families.

Through the Unknown Causes of Kidney Disease (UCKD) Coalition, the American Kidney Fund is working to improve access to this gap in care by advocating for federal legislation that will allow direct Medicare reimbursement to genetic counselors. The coalition also supports recommendations for annual kidney screening for higher risk populations, which is under active consideration by the US Preventive Services Task Force.

HCPs need, want guidance

Our survey also found that most doctors do desire more information about genetic testing and clearer diagnostic guidelines to support their patients with chronic kidney disease. This highlights our need for comprehensive guidelines for genetic screening and testing in kidney disease care. Such guidelines will help ensure high quality care is consistently provided to all patients, regardless of where they live or seek treatment. Additionally, increased education for doctors, such as more diagnostic training on genetic or rare disorders for primary care physicians and nephrologists, can raise awareness of the role genetic testing plays in arriving at an accurate diagnosis and ensure practitioners feel informed about the latest standards in patient care.

And finally, engaging patients in their care and helping them advocate for themselves is an important aspect of this work. For patients of color, who are disproportionately impacted by kidney failure, culturally relevant outreach is necessary to educate them on the options available for reaching an accurate diagnosis. Developing accessible and culturally competent resources and support systems for all patients will arm them and their caregivers with the right information to seek and fully understand a kidney disease diagnosis as well as improve patient-provider communication.

As the science advances and we learn more about the nuances of kidney disease and its various causes, we need policymakers, regulators, medical societies, insurance providers and others within the healthcare system to support the need for increased genetic testing and help drive much needed change to improve kidney care for all.

1. American kidney fund survey underscores need to expand testing for chronic kidney disease and increase awareness of rare kidney diseases. News release. American Kidney Fund. April 7, 2022. Accessed June 21, 2023.
2. Khan A, Turchin, M. C., Patki, A.,et al. Genome-wide polygenic score to predict chronic kidney disease across ancestries. Nature Med. 2022;28: 1412–1420. doi: 10.1038/s41591-022-01869-1