A positive pneumococcal urinary antigen test promotes narrow spectrum antibiotic use in patients with non-invasive pneumococcal pneumonia

Diagn Microbiol Infect Dis. 2020 Feb;96(2):114897. doi: 10.1016/j.diagmicrobio.2019.114897. Epub 2019 Oct 5.

Abstract

Background: We compared changes in antibiotics in patients diagnosed with noninvasive pneumococcal pneumonia (NPP) by pneumoccocal urinary antigen tests or respiratory cultures.

Methods: We compared patients diagnosed by pneumococcal urinary antigen tests or respiratory cultures that grew Streptococcus pneumoniae. We assessed the time from sample receipt to final result and antibiotic regimens, including an Antibiotic Spectrum Index (ASI).

Results: Seventy-two cases of NPP were diagnosed by pneumococcal urinary antigen and 87 by respiratory cultures, with a median time from sample receipt to final result of 0.21 days (interquartile range (IQR) 0.17-1.17) and 3.21 days (IQR 3.17-4.21 days), respectively. Among 123 cases without antibiotic allergies, between days 0 and 2, the ASI decreased in 36% (18/50) of cases diagnosed by urinary antigen compared to 10% (7/73) of cases diagnosed by respiratory culture (P < 0.01).

Conclusions: Positive pneumococcal urinary antigen tests lead to early deescalation of antibiotics more frequently than respiratory cultures.

Keywords: Antimicrobial stewardship; Noninvasive pneumococcal pneumonia; Rapid diagnostic tests; Streptococcus pneumoniae; Veterans Affairs.

MeSH terms

  • Aged
  • Anti-Bacterial Agents / pharmacology
  • Anti-Bacterial Agents / therapeutic use
  • Antigens, Bacterial / immunology*
  • Antigens, Bacterial / urine
  • Female
  • Humans
  • Immunoassay* / methods
  • Male
  • Middle Aged
  • Pneumococcal Infections / diagnosis*
  • Pneumococcal Infections / drug therapy
  • Pneumococcal Infections / immunology*
  • Pneumococcal Infections / urine
  • Streptococcus pneumoniae / immunology*
  • Treatment Outcome
  • Urinalysis

Substances

  • Anti-Bacterial Agents
  • Antigens, Bacterial