New York, Dec 23 (IANS): Covid-19 patients with a secondary blood infection were significantly sicker upon hospital admission, had longer hospital stays and poorer outcomes, new research has found.

A bloodstream infection (BSI) is defined as one or more positive blood cultures associated with systemic signs of infection such as fevers, chills, and/or hypotension, according to the International Society for Infectious Diseases.

While primary BSIs occur without another defined nidus of infection, secondary BSIs develop from a detectable area of infection as the source of the bacteremia, it said.

In the study, published in the journal Clinical Infectious Diseases, the researchers looked at 375 patients diagnosed with severe Covid-19 from March to May 2020.

Of that group, they sampled 128 cases who had secondary bloodstream infections, 92 per cent of which were bacterial infections.

"These patients were more likely to have altered mental status, lower per cent oxygen saturation, septic shock and to be admitted to the intensive care unit compared to those without bloodstream infections," said co-lead author Pinki Bhatt, Assistant Professor at Rutgers Robert Wood Johnson Medical School in New Jersey, US.

The researchers also found that patients who needed more advanced types of supplemental oxygen upon hospital admission had higher odds of secondary bloodstream infections.

The in-hospital mortality rate for these patients was more than 50 per cent, but the study reported these deaths were associated with, not caused by, the condition.

According to the study, infections in Covid-19 patients may have contributed to the severity of illness or it may reflect other underlying physiological and immunological complications of Covid-19.

The study showed that the most common cause of secondary bloodstream infections was unknown or not determined.

The study found that 80 per cent of all the patients in the study received antimicrobials at some point during hospitalisation, including those who did not have bloodstream infections.

"This likely reflects clinicians' inclination to administer antimicrobials given the limited information on the natural course of this novel disease," Bhatt said.

She noted that further studies are needed to better understand when to suspect and treat empirically for secondary bloodstream infections in severe Covid-19.