Septic arthritis caused by Brucella melitensis - An orthopedic chal-lenge (11194)

ABSTRACT

Introduction The zoonotic infection with Brucella melitensis can be acquired by inges-tion of unpasteurized goat's or sheep's milk. The infection is common in Eastern Mediterranean countries (EMC), but rare in western Europe (6 cases in Switzerland, 2021). When evaluating patients with symptoms of septic arthritis, brucellosis is not the foremost differential diagnosis. How-ever, with the increasing population of people from EMC in western Eu-rope, the incidence may be rising. We present a patient who was initially suspected to suffer from Long-COVID-Syndrome (LCS), which underscores the relevance of this case in a pandemic situation. Methods/Results A 58-year-old male patient was admitted to the emergency department with a painful right knee effusion after a minor trauma. Additionally, he suffered from fatigue, subfebrile temperatures, back pain and myalgias for more than two months. He was suspected to suffer from LCS after a mild COVID-19 three months earlier. The culture of the arthrocentesis (14.400 cells/mul with 61% polynuclear cells) unexpectedly turned positive for B. melitensis. The patient declared that he had been drinking three liters of unpasteurized goat's milk to cure the presumptive LCS. To ensure staff safety, arthroscopic lavage was postponed until brucella-active antibiotics had been administered for at least 24 hours. Surgery was performed under strict infection control measures to avoid generating aerosols. According to Duke, one major (continuous bacteremia over 14 days) and 2 minor criteria (fever, most probably septic embolic gonarthritis) were fulfilled. Therefore, possible endocarditis had to be assumed although transesophageal echocardiography was normal. Antibiotic treatment was escalated to a quadruple regimen (intravenous gentamicin for three weeks;as well as oral doxycycline, trimethoprim/sulfomethoxazole and rifampin for at least 3 months). The clinical recovery - still under treatment - is protracted with slowly improving knee pain and normalizing signs of inflammation. Conclusion Although B. melitensis is a rare pathogen in Switzerland, orthopedic sur-geons, rheumatologists and infectious disease specialists need to be aware of diseases with low incidence and non-specific symptoms espe-cially in times of a global pandemia. A high index of suspicion is needed in patients related to EMC. When brucellosis is confirmed, strict infection control measures to protect staff involved in aerosol generating proce-dures must be adopted.