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Toxic anterior segment syndrome following penetrating keratoplasty
Philip Maier1, Florian Birnbaum, Daniel Böhringer
1University Eye Hospital, Freiburg, Germany. philip.maier@uniklinik-freiburg.de
Objectives:
To describe an outbreak of toxic anterior segment syndrome (TASS) following penetrating keratoplasty (PK) and to examine its possible causes.
Methods:
Owing to a series of TASS following PK between June 6, 2007, and October 2, 2007, we reviewed the records of all patients who had undergone PK during that time. In addition to routine microbial tests on organ culture media, we looked for specific pathogens and endotoxins in all of the materials used for organ culture or PK. Furthermore, we analyzed all of the perioperative products and instrument processing.
Results:
Of the 94 patients who underwent PK, we observed 24 cases of postoperative sterile keratitis. Causal research revealed that the accumulation of cleaning substances or heat-stable endotoxins on the surface of the routinely used guided trephine system was most likely responsible for the TASS.
Conclusions:
To our knowledge, this is the first report on TASS following PK. Suboptimal reprocessing of surgical instruments may be an important cause of TASS as in this series the TASS-like symptoms resolved after modified instrument-cleaning procedures. The standardization of protocols for processing reusable trephine systems might prevent outbreaks of TASS following PK.
Insights
An outbreak of toxic anterior segment syndrome (TASS) after penetrating keratoplasty (PK) was linked to contaminated surgical instruments. Improving instrument cleaning protocols resolved TASS symptoms, suggesting a need for standardized reprocessing to prevent future cases.
Area of Science:
- Ophthalmology
- Microbiology
- Surgical Science
Background:
- Toxic anterior segment syndrome (TASS) is a serious postoperative complication.
- Penetrating keratoplasty (PK) is a common corneal transplant procedure.
- Outbreaks of TASS can significantly impact patient outcomes.
Purpose of the Study:
- To investigate an outbreak of TASS following PK.
- To identify the causative agents and contributing factors of TASS.
- To propose preventive measures for TASS after PK.
Main Methods:
- Retrospective review of patients undergoing PK during a specific period.
- Microbial and endotoxin testing of surgical materials and instruments.
- Analysis of perioperative products and instrument reprocessing procedures.
Main Results:
- 24 cases of TASS-like sterile keratitis were observed in 94 PK patients.
- Contaminated guided trephine systems with cleaning substances or endotoxins were identified as the likely cause.
- TASS symptoms resolved after implementing modified instrument-cleaning procedures.
Conclusions:
- This is the first reported outbreak of TASS following PK.
- Suboptimal surgical instrument reprocessing is a significant risk factor for TASS.
- Standardizing trephine system reprocessing protocols can prevent TASS outbreaks after PK.
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