An unusual case of seronegative, 16S PCR positive infection.

Introduction: is a zoonotic infection commonly diagnosed by isolation of the organism from blood culture or positive serological testing. It is an uncommon cause of a pyrexia of unknown origin in the United Kingdom.

Case Presentation: We describe the case of a 14-year-old girl with no history of travel who presented with pyrexia, weight loss, arthralgia, multiple splenic abscesses and a subsequent pleural effusion, the latter of which isolated a species on 16S rRNA PCR. The patient responded well to initiation of treatment for brucellosis and on repeat imaging, after 3 months, the splenic abscesses had resolved.

Conclusion: This unique case demonstrates uncommon complications of brucellosis and the challenges of diagnosing the organism, the latter of which can be alleviated by the utilization of molecularbased technologies. This patient had a negative serology result for brucellosis, which highlights the need to interpret serology results with caution in non-endemic regions for brucellosis.