Identifying Pneumonia With DNA Test Can Aid in Faster COVID-19 Treatment

Causative organism details in patients with ICU-acquired infections has had limited reporting.

Investigators from the University of Cambridge and Cambridge University Hospitals NHS Foundation Trust have developed a DNA test that rapidly identifies secondary infections in patients with the coronavirus disease 2019 (COVID-19). The results were published in the journal Critical Care.

Patients who are hospitalized with COVID-19 and have secondary infections have double the risks of developing pneumonia while on ventilation when compared to those who do not have the virus. Mechanical ventilation is often the only way to keep those with a severe form of the disease alive, but it makes them more susceptible to other infections from bacteria and fungi.

Investigators developed the method using a high throughput DNA test that is able to give physicians information they need to start treatment in a few short hours rather than days that current tests require. The ability for quicker results offers the chance for better treatments for infections.

"Early on in the pandemic we noticed that COVID-19 patients appeared to be particularly at risk of developing secondary pneumonia, and started using a rapid diagnostic test that we had developed for just such a situation," Andrew Conway Morris, a co-author on the study said. "Using this test, we found that patients with COVID-19 were twice as likely to develop secondary pneumonia as other patients in the same intensive care unit."

The test employs a multiple polymerase chain reaction (PCR) that detects bacterial DNA which can be completed in around 4 hours, creating a shorter window for the bacteria to grow. The technology runs multiple PCR reactions in parallel, which allows the test to simultaneously detect 52 different pathogens, most importantly ones that can infect the lungs.

For the first time, the test has been used in routine clinical practice and has been approved by hospitals. The investigators believe that similar approaches can provide a benefit if applied more broadly.

"We found that although patients with COVID-19 were more likely to develop secondary pneumonia, the bacteria that caused these infections were similar to those in ICU patients without COVID-19," Mailis Maes, the lead author on the study said. "This means that standard antibiotic protocols can be applied to COVID-19 patients."