Moiz Ahmed Khan

Abstract

INTRODUCTION: Three patients who underwent angioplasty procedure at a cardiac tertiary care hospital between 29th December 2024 to 30th January 2025, developed high-grade fever with chills within 12 hours of the procedure. Blood culture from these patients yielded growth of pan-sensitive Pseudomonas aeruginosa.

METHODS: A comprehensive outbreak investigation was undertaken by the Infection control department of a cardiac tertiary care center in Karachi, Pakistan in February 2025. We followed established outbreak protocols incorporating environmental assessment and collection of surface samples from catheterization laboratories along with culturing intravenous infusates used during procedures.

RESULTS: Environmental and surface samples from the catheterization laboratories were negative. However, culture from contrast dye bottles used during the procedures yielded growth of P. aeruginosa exhibiting identical antimicrobial susceptibility pattern to the outbreak strain, establishing a direct microbiological link. Hence, all the lots of the respective contrast dye were immediately retracted from further used on 13th February 2025, after which no further cases were identified. Our investigation indicated the contaminated contrast dye as the source of this outbreak considering the temporal relationship between infection onset and dye administration, concordance between the outbreak strains and those isolated from the contaminated contrast, and cessation of new cases following discontinuation of the contrast.

CONCLUSION: We report a successful investigation of a Pseudomonas aeruginosa outbreak in patients who underwent angioplasty procedure at a cardiac tertiary care hospital. A comprehensive investigation into the outbreak source should include a thorough assessment of the environment, collection of surface samples and microbiological assessment of intravenous fluids.