# A Case of Methicillin-Sensitive Staphylococcus aureus Septic Arthritis Causing Septic Pulmonary Emboli in a Healthy Young Adult

## TL;DR

A healthy young man developed a rare case of septic arthritis and lung infections caused by a common staph bacteria, highlighting the need to consider joint infections as a possible source.

## Contribution

This case report highlights an unusual presentation of disseminated MSSA infection in an immunocompetent adult without endocarditis.

## Key findings

- A 21-year-old healthy man developed MSSA septic arthritis and septic pulmonary emboli.
- No evidence of endocarditis was found, and the patient recovered after six weeks of IV cefazolin.
- The case suggests septic arthritis can be a primary source of disseminated infection in healthy individuals.

## Abstract

Disseminated Staphylococcus aureus (S. aureus) infection in healthy adults is uncommon and usually linked to endocarditis, intravenous (IV) drug use, or immunocompromise. I describe a 21-year-old man who presented with acute right hip pain, fever, and difficulty bearing weight. Evaluation revealed right hip septic arthritis complicated by bilateral septic pulmonary emboli (SPE) and right femoral vein thrombosis. Transthoracic and transesophageal echocardiograms showed no evidence of endocarditis. Blood and joint cultures grew methicillin-sensitive S. aureus (MSSA). He completed six weeks of continuous-infusion intravenous cefazolin with good clinical recovery. This case demonstrates that disseminated MSSA infection with septic emboli can arise in immunocompetent adults without endocarditis and emphasizes the need to consider septic arthritis as a potential primary source.