Use ‘fingerprints’ to quickly detect infection in dialysis patients

"Infection is the biggest obstacle for any dialysis patient as it can seriously hamper their treatment and their chances of leading a normal life," says Nicholas Topley. "Through my own experience as a transplant patient, my research in dialysis patients over the past 25 years and in talking to patient groups, I observed that conventional tests just aren't quick enough and are often inconclusive, which can be a fatal shortcoming. (Credit: "dialysis patient" via Shutterstock)

Scientists may have found a way to speed up the detection of bacterial infection in dialysis patients by using the patient’s immune system to identify the pathogen.

Dialysis patients with chronic kidney disease need fast and accurate diagnosis of infection so doctors can administer the correct antibiotic treatment to ensure a fair chance of recovery. Nicholas Topley and Matthias Eberl from Cardiff University’s School of Medicine have shown proof-of-concept that a patient’s unique immune response to infection can be used to accurately detect within hours which organism is causing infection.

Together with commercial partners, the group is using these new insights, which they call “immune-fingerprints,” to inform the development of a point-of-care test.

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“Infection is the biggest obstacle for any dialysis patient as it can seriously hamper their treatment and their chances of leading a normal life,” says Topley. “Through my own experience as a transplant patient, my research in dialysis patients over the past 25 years and in talking to patient groups, I observed that conventional tests just aren’t quick enough and are often inconclusive, which can be a fatal shortcoming.

Topley says they decided that more needed to be done to give patients every chance for a successful recovery and began looking to the body’s own natural defenses for inspiration.

“The immune system is capable of rapid, sensitive, and specific detection of a broad spectrum of microbes, which has been optimized over millions of years of evolution,” explains Matthias Eberl from Cardiff’s Institute of Infection and Immunity.

“A patient’s early immune response is therefore likely to provide a far better insight into the true nature and severity of microbial infections than current tests, which are based on the microbiological identification of the potential pathogen—a concept introduced by Robert Koch more than a century ago.”

Distinct immune signature

To test this theory, scientists performed a detailed immunological and microbiological analysis of samples obtained from peritoneal dialysis patients with acute infection/peritonitis (a condition in which the thin tissue that lines the inner wall of the abdomen becomes inflamed). Laboratory tests revealed that each bacterial infection leaves a distinct immune signature and robustly discriminates between different types of infection.

This is the first time that scientists have attempted—or succeeded—to distinguish soluble and cellular components in defining responses to specific germs in an infected human and to translate the idea of immune fingerprints into a potential diagnostic tool. The research findings are published in the Journal of the American Society of Nephrology.

The data provide proof-of-concept that using immune fingerprints to inform the design of point-of-care tests will help target antibiotic prescriptions and improve patient management. With the immune fingerprint test, doctors would be able to differentiate rapidly between serious and benign infections and be able to prescribe suitable and accurate treatments.

A Baxter Healthcare’s Renal Discoveries Extramural Grant, the National Institute for Social Care and Health Research, and the Welsh Government funded the research.

Source: Cardiff University