Title : A rare case of brucellosis relapse
Abstract:
Introduction: Brucellosis is a zoonotic infection transmitted through unpasteurized food or direct contact with infected animals. With over 500,000 cases annually, relapses are rare, occurring in 5-30% of cases, typically within six months and in immunocompromised individuals or those with inadequate treatment. This report highlights an uncommon brucellosis relapse in a non-endemic area, occurring more than a year after the initial treatment.
Case Presentation: The patient is a 56-year-old male with a medical history of heart failure, hypertension, and a prior history of brucellosis requiring prolonged antibiotic treatment a year ago. He presented with sudden-onset episodic fever, headache, arthralgia, and myalgia. His labs were unremarkable except for mild leukocytosis and hypokalemia. Blood cultures and serum lactate were normal. He initially denied any history of contact with animals or animal products but later endorsed a history of recent contact with feral pigs. Brucella IgM and IgG, as well as antibody agglutination tests, were sent. In the meantime, he was empirically treated with doxycycline, rifampin, and gentamicin, given his prior history of brucellosis and recent contact with pigs. The patient showed significant improvement in symptoms over his 8-day hospital stay. He was discharged with a 6-week course of rifampin and doxycycline. Within a few days post-discharge, the patient's Brucella antibody tests returned positive, thus confirming our suspicions.
Discussion: Brucellosis, also known as "Undulant fever", "Mediterranean fever" or "Malta fever" is a highly common zoonotic disease worldwide. It is also an important public health concern that can have a widespread economic impact on the livestock industry in endemic areas. Clinical features of brucellosis classically include fever, malaise, night sweats, arthralgia, myalgia, hepatosplenomegaly, and/or lymphadenopathy. The physical examination is most often normal, although lymphadenopathy, splenomegaly, and hepatomegaly are sometimes present. A CBC typically shows neutropenia and anemia, but sometimes thrombocytopenia secondary to hepatosplenomegaly is also seen. A definitive diagnosis is made by culturing blood, body fluids or tissue, or by a greater than four-fold rise in brucella antibody titers between acute and convalescent-phase serum specimens obtained >2 weeks apart. However, in common practice, a presumptive diagnosis may be made by antibody titer >1:160 via agglutination test or by PCR detection of Brucella DNA in a clinical specimen. Brucellosis should be suspected in patients with relevant signs and symptoms, in the setting of relevant epidemiological exposure including consumption of unpasteurized dairy products, animal exposure in an endemic/non-endemic area, occupational exposure, or history of prior brucellosis infection. Although rare, suspected cases of brucellosis relapse should be treated empirically with a standard antibiotic regimen of Doxycycline plus Gentamycin, Streptomycin, or Rifampin. Early treatment is key in preventing complications such as endocarditis or meningitis.
Conclusion: This case is an excellent representation of the fact that although brucellosis relapse is rare, it is appropriate and imperative to empirically treat patients with brucellosis-like symptoms and/or a history of prior brucellosis with standard antibiotic regimens, even if microbiological confirmation is pending.
