Brucellosis Reactivation after 28 Years

To the Editor: Approximately 10% of patients with brucellosis experience a relapse, 90% of which occur within a year after discontinuation of antimicrobial drug therapy (1,2). Here we report a patient who had brucel-losis in a disease-endemic area, immigrated to a brucellosis-free region, and experienced focal reactivation in her gallbladder 28 years later. To our knowledge, this interval is among the longest reported asymptomatic intervals between a fi rst brucellosis episode and reactivation. The case suggests that physicians should not disregard remote histories of brucellosis and past residence in brucellosis-endemic areas when confronted with possible reactivation disease. A woman, born in 1955, had prolonged fever without focal symptoms in 1981 and had received a diagnosis of brucellosis while living near Valencia, Spain. The brucellosis was attributed to an episode of eating unpasteurized cheese from the local dairy and was successfully treated. She immigrated to Switzerland in 1990 and was well until March 2009, when malaise and right upper quadrant pain developed, without fever. She was otherwise healthy and did not take any medication. Computed tomography (CT) scan showed a mass contiguous with the gallbladder, extending intrahe-patically, with concentric calcifi ca-tions and multiple gallstones (Figure). Gallbladder cancer was suspected, but when a laparotomy was performed, an acutely infl amed gallbladder with a surrounding infl ammatory mass was found and excised. Gallbladder cultures on standard media (Columbia agar with 5% sheep's blood, chocolate agar, Brucella blood agar, and brain-heart infusion broth) were discarded when they remained sterile after 5 days of incubation. Histopathologic examination showed granulomatous cholecystitis, and the patient was referred for infectious disease consultation. Formalin-fi xed gallbladder tissue was negative for Mycobacterium tuberculosis complex DNA but positive for Brucella melitensis by PCR (3). Blood cultures (BACTEC Plus Aerobic/F and Anaerobic/F [Becton Dickinson, Allschwil, Switzerland], incubated for 10 days) remained sterile. No Brucella DNA was detected in blood and serum (1,2), and a rose bengal serum agglutination test was negative for anti-Brucella antibodies. Because of the rarity of the manifestation (late reactivation) and location (gallbladder), plus a residual abscess shown on CT scan 8 weeks after surgery , prolonged treatment with doxy-cycline and rifampin was administered for 3 months, with gentamicin added during the initial 2 weeks (4). Nine months after antimicrobial drug therapy was discontinued, the patient remains well. Switzerland reported the elimination of animal brucellosis in 1963 (5) and has offi cially been brucellosis-free The last case of B. …