Point-of-care PCR may help guide antibiotic choice and improve pneumonia treatment

A study published in PLOS ONE has concluded that using respiratory POC does not appear to be effective in reducing antibiotic use in a setting with low antimicrobial resistance and already prudent antibiotic use. However, it may help ensure targeted and appropriate treatment in a restrictive antibiotic setting and support a restrictive strategy. The COVID-19 pandemic and low transmission of common respiratory viruses during the study period may have impacted the results.

We need rapid and accurate detection of pathogens in community-acquired pneumonia (CAP) to use appropriate antibiotics and slow down antibiotic resistance development. The study aimed to compare the effect of adding point-of-care (POC) polymerase chain reaction (PCR) detection of respiratory pathogens to standard care with standard care only (SCO) on antibiotic prescriptions after acute hospital admission.

They conducted an open-label, multicenter, parallel-group, superiority RCT at three Danish medical emergency departments from March 2021 to February 2022. Adults with suspected CAP during daytime weekdays were included and randomly assigned (1:1) to POC-PCR or SCO analysis of respiratory samples. Two hundred ninety-four patients with collected samples were randomly assigned to POC-PCR (n = 148, 50.4%) or SCO (n = 146, 49.6%). The study used logistic regression and Huber–White clustered standard errors for the prescription of antibiotic treatment. The study included intention-to-treat and per-protocol analysis.

Key findings from the study are:

• Loss to follow-up comprises three patients in the POC-PCR and none in the SCO group.
• There was no difference in the primary outcome of prescriptions of no or narrow-spectrum antibiotics four hours after admission for the POC-PCR and SCO.
• The prescriptions were more targeted at four h (OR 5.68) and 48 h (OR 4.20)and more adequate at 48 h (OR 2.11) and on day 5 in the POC-PCR group (OR 1.40).
• There was no difference between the groups about intensive care unit (ICU) admissions, readmission within 30 days, length of stay, 30-day mortality and in-hospital mortality.

· The POC-group patients showed a non-statistically significant shortening of hospital stay by approximately one day.

· The POC group treated more patients with targeted antibiotics within 48 hours and five days after admission.

Antimicrobial resistance is low in Denmark, and most Haemophilus influenzae and Streptococcus pneumoniae are susceptible to benzylpenicillin. Danish guidelines recommend narrow-spectrum penicillin for milder CAP cases and broad-spectrum antibiotics for severe cases. CAP diagnosis is based on clinical symptoms and unspecific diagnostic tools like auscultation, chest radiography, blood tests, and microbiological analysis of sputum samples.

They said that in a setting with limited antibiotic use, point-of-care - polymerase chain reaction (POC-PCR) did not increase the number of patients treated with narrow-spectrum or without antibiotics. However, it showed potential for more targeted and appropriate antibiotic use. A study limitation was the COVID-19 pandemic, which led to low respiratory virus transmission.

Reference:

: Cartuliares MB et al. Evaluation of point-of-care multiplex polymerase chain reaction in guiding antibiotic treatment of patients acutely admitted with suspected community-acquired pneumonia in Denmark: A multicentre randomized controlled trial. PLoS Med 20(11): e1004314. https://doi.org/10.1371/journal.pmed.1004314