[Human brucellosis: three faces of an insidious zoonosis]

Human brucellosis is a prevalent zoonotic disease in Tunisia, especially in rural areas with significant livestock activity. The disease can manifest as localized or systemic forms, and its clinical presentation is highly polymorphic. Here, we present three cases that illustrate this clinical diversity.

A 69-year-old diabetic man living in a rural area presented with a painful cervical swelling. Computed tomography revealed cervical cellulitis and pyomyositis. Culture of the pus from the cellulitis yielded positive results for Brucella spp., and the patient was treated with doxycycline and rifampicin for six weeks, along with surgical drainage. The outcome was favorable.

A 48-year-old male intravenous drug user was hospitalized due to a prolonged fever associated with a heart murmur. Echocardiography revealed tricuspid vegetation measuring 34×24 mm and moderate tricuspid regurgitation. A blood culture revealed Brucella spp., and treatment consisted of a combination of antibiotics, including doxycycline and rifampicin, as well as valve surgery. The outcome was favorable with this combined treatment.

A 50-year-old cirrhotic patient was admitted with febrile hepatic encephalopathy that did not improve with empirical antibiotic therapy. Blood cultures isolated Brucella spp., and appropriate treatment led to a marked clinical improvement.

Human brucellosis presents with a variety of clinical manifestations that complicate its diagnosis. In Tunisia, clinical vigilance is essential for the early diagnosis and appropriate management of the disease, particularly in at-risk patients. Prospective studies are needed to better define treatment protocols, especially for complex forms of the disease.