# Sonographic Evaluation of an Inguinal Bubo from Bartonella henselae: A Case Report

## TL;DR

This case report describes the use of ultrasound to identify a bubo caused by Bartonella henselae in an emergency department setting.

## Contribution

The paper provides a sonographic case of a Bartonella henselae bubo, expanding POCUS knowledge in rare soft tissue infections.

## Key findings

- POCUS identified a necrotic suppurative lymph node in a patient with a 20-pound weight loss.
- Serology confirmed Bartonella henselae infection, leading to azithromycin treatment and symptom improvement.
- The case highlights the importance of recognizing buboes via ultrasound for accurate diagnosis and management.

## Abstract

Emergency physicians can use point-of-care ultrasound (POCUS) to identify lymph nodes in certain clinical scenarios, and advanced users can determine significant information (such as concerns for malignancy or differentiating them from abscesses for incision and drainage) based on a large volume of literature and images associated with those pathologies.1 However, current literature does not contain a similar volume of images and cases of suppurative lymph nodes, or buboes, limiting the ability to make the diagnosis sonographically at the bedside.

We report on a man who presented to the emergency department (ED) with a worsening inguinal mass that changed size with positioning, as well as a 20-pound weight loss occurring over the course of a month. Point-of-care ultrasound of the mass was concerning for a necrotic suppurative lymph node, which was further evaluated with cross-sectional imaging. The patient was admitted for a biopsy to rule out malignancy. He was discharged with serologies for Bartonella henselae pending, which later returned positive. The patient was then switched to azithromycin with significant improvement of his symptoms.

As POCUS becomes the modality of choice for rapid assessment of soft tissue masses in the ED, familiarity with less common variants of soft tissue infections such as buboes can help with medical decision-making, risk stratification, and further workup. This sonographic description of a bubo caused by a common zoonotic infection will enable clinicians to familiarize themselves with their appearance.