# Pyogenic liver abscess and sepsis caused by mixed anaerobic bacteria in an immunocompetent adult: a case report

## TL;DR

A healthy 64-year-old woman developed a rare liver infection and sepsis caused by multiple gut-origin anaerobic bacteria, successfully treated with antibiotics.

## Contribution

Reports a rare case of pyogenic liver abscess and sepsis from mixed anaerobic bacteria in an immunocompetent adult.

## Key findings

- mNGS identified four anaerobic bacteria in blood and abscess fluid.
- Three bacteria were confirmed by culture.
- Treatment with meropenem and metronidazole led to recovery.

## Abstract

Anaerobic bacterial communities in the digestive tract play an important role in digestive tract infections and aspiration pneumonia. However, ectopic infections originating from these communities are uncommon.

We present a rare case of a 64-year-old immunocompetent female was admitted with no significant medical history who developed a pyogenic liver abscess and sepsis caused by multiple anaerobic bacteria of digestive tract origin. Metagenomic next-generation sequencing (mNGS) detected four types of anaerobic bacteria in both peripheral blood and abscess puncture fluid. Culture confirmed the presence of three of these microorganisms. Treatment with a combination of meropenem and metronidazole resulted in the patient’s subsequent recovery and discharge.

This report highlights the occurrence of ectopic infections caused by multiple anaerobic bacteria leading to pyogenic liver abscess and sepsis, underscoring the importance of considering anaerobic bacteria and conducting rapid comprehensive pathogen detection in clinical practice.