# Management of an infection from NDM-1-producing Escherichia coli with susceptibility to aztreonam

## TL;DR

A patient with a severe infection caused by a drug-resistant bacteria was successfully treated using aztreonam, showing it could be an effective treatment option.

## Contribution

Demonstrates successful treatment of NDM-1-producing Escherichia coli infection using aztreonam-based therapy in a clinical case.

## Key findings

- A patient with NDM-1-producing Escherichia coli was successfully treated with aztreonam plus ceftazidime-avibactam.
- Aztreonam-based therapy may be effective for treating infections caused by ATM-susceptible NDM-producing bacteria.

## Abstract

Infections with New Delhi metallo-beta-lactamase (NDM)-producing Enterobacterales are increasingly reported in the United States, with some isolates being reported susceptible to aztreonam (ATM) alone. However, data for the use of ATM as monotherapy are lacking, and current guidelines recommend the use of cefiderocol (FDC) or ceftazidime-avibactam (CZA) plus ATM for severe infections due to concern for co-production of serine beta-lactamases.

Here, we report a case of necrotizing soft tissue and surgical hardware infection in an immunocompromised patient with NDM-1-producing Escherichia coli that was susceptible to ATM, who was successfully treated with ATM + CZA followed by transition to ATM and minocycline.

This case demonstrates the potential efficacy of ATM therapy, at least for part of the treatment course. Further studies are needed regarding treatment outcomes for ATM-susceptible NDM-producing Enterobacterales infections.