Positron Emission Tomography Imaging with 2-[18F]F- p-Aminobenzoic Acid Detects Staphylococcus aureus Infections and Monitors Drug Response

ACS Infect Dis. 2018 Nov 9;4(11):1635-1644. doi: 10.1021/acsinfecdis.8b00182. Epub 2018 Aug 17.


Staphylococcus aureus is the leading cause of life-threatening infections, frequently originating from unknown or deep-seated foci. Source control and institution of appropriate antibiotics remain challenges, especially with infections due to methicillin-resistant S. aureus (MRSA). In this study, we developed a radiofluorinated analog of para-aminobenzoic acid (2-[18F]F-PABA) and demonstrate that it is an efficient alternative substrate for the S. aureus dihydropteroate synthase (DHPS). 2-[18F]F-PABA rapidly accumulated in vitro within laboratory and clinical (including MRSA) strains of S. aureus but not in mammalian cells. Biodistribution in murine and rat models demonstrated localization at infection sites and rapid renal elimination. In a rat model, 2-[18F]F-PABA positron emission tomography (PET) rapidly differentiated S. aureus infection from sterile inflammation and could also detect therapeutic failures associated with MRSA. These data suggest that 2-[18F]F-PABA has the potential for translation to humans as a rapid, noninvasive diagnostic tool to identify, localize, and monitor S. aureus infections.

Keywords: MRSA; PET; bacteria; folate; imaging; infection.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • 4-Aminobenzoic Acid / pharmacology*
  • Animals
  • Cross Infection / diagnosis
  • Cross Infection / diagnostic imaging
  • Cross Infection / microbiology
  • Female
  • Methicillin-Resistant Staphylococcus aureus / drug effects
  • Methicillin-Resistant Staphylococcus aureus / isolation & purification*
  • Mice
  • Mice, Inbred CBA
  • Positron Emission Tomography Computed Tomography*
  • Rats
  • Rats, Sprague-Dawley
  • Staphylococcal Infections / diagnosis*
  • Staphylococcal Infections / diagnostic imaging*


  • 4-Aminobenzoic Acid