# Case Report: Fatal Necrotizing Pneumonia by Exfoliative Toxin etE2-Producing Staphylococcus aureus Belonging to MLST ST152 in The Netherlands

## TL;DR

A deadly case of pneumonia caused by a rare strain of Staphylococcus aureus producing a new toxin is reported, highlighting its potential global threat.

## Contribution

Identification of a novel exfoliative toxin (etE2) in a specific S. aureus lineage linked to severe infections.

## Key findings

- The S. aureus isolate produced exfoliative toxin etE2 and belonged to the ST152 lineage.
- The etE2 gene was co-located with edinB, contributing to tissue destruction.
- This lineage is associated with severe infections and global spread.

## Abstract

We present a case of fatal necrotizing Staphylococcus aureus pneumonia with underlying influenza A (H3) infection. Next-generation-sequencing-based analysis revealed that the S. aureus isolate harbored the newly recognized exfoliative toxin etE2 gene. Molecular epidemiologic analysis showed that the isolate belonged to the MSSA ST152 lineage, harboring PVL genes and edinB co-located to etE2 as distinctive virulence factors. The etE2 gene is present in all isolates of this lineage co-located to the exotoxin gene edinB, both implicated in the destruction of tissue integrity. We alert as to the global emergence of this lineage causing serious infections in patients.