Work

Mycobacterium bovisin Captive Siberian Tiger

Year: 2003

Type: article

Abstract: We report the first case of pulmonary tuberculosis caused by Mycobacterium bovis subsp.caprae in a captive Siberian tiger, an endangered feline.The pathogen was isolated from a tracheal aspirate obtained by bronchoscopy.This procedure provided a reliable in vivo diagnostic method in conjunction with conventional and molecular tests for the detection of mycobacteria.M ycobacterium bovis, a member of the M. tuberculosis complex (MTBC), can cause tuberculosis in a wide range of domestic and wild animals and also in humans (1,2).Routine differentiation of M. bovis is based on a number of phenotypic characteristics and biochemical tests (2).M. bovis shows dysgonic growth on Löwenstein-Jensen (LJ) medium and has been described as negative for nitrate reduction and niacin accumulation (2).As a further criterion for the differentiation of M. bovis, intrinsic resistance to pyrazinamide (PZA) has been described (2).However, more recently, PZA-susceptible strains of M. bovis were found in Spain and Germany; these strains were also characterized by specific molecular techniques (3-5).As a consequence, M. bovis was split into two subspecies: M. bovis subsp.bovis, which showed resistance to PZA, and M. bovis subsp.caprae, which was sensitive to PZA (6,7).M. bovis subsp.caprae was initially isolated from sheep and goats in Spain (3,4,7); however, further studies confirm its infectivity in humans, cattle, and red deer (6,8).We report the unusual case of a M. bovis subsp.caprae infection in a captive Siberian tiger. Case ReportAn 8-year-old male Siberian tiger at the Budapest Zoological and Botanical Garden had episodes of coughing in October 2001.Because the coughing did not stop in 6 to 7 days, an expectorant (Bisolvon; Boehringer Ingelheim Vetmed Gmbh., Ingelheim am Rhein, Germany) was given for 10 days.His condition showed a temporary improvement; however, after a few weeks, the animal started coughing again, and his appetite decreased.Amoxicillin plus clavulanic acid (Amoksiklav; Lek Animal Health, Ljubljana, Slovenia) and ketoprophen (Ketofen, Merial, Lyon, France) therapy was given for 7 days.The tiger's condition did not show any notable improvement.In addition, in May 2002, the animal's respiratory rate became elevated, he became dyspneic and emaciated, and his daily activity substantially decreased.Further antibacterial treatment was administered (cefatroxil, Cefa-cure; Intervet, Boxmeer, the Netherlands) during that month without clinical effect.At that point, the animal was anesthetized, and tracheoscopy was performed with a flexible 56-cm bronchoscope (Olympus B3R; Tokyo, Japan (Figure 1).The examination found a large amount of purulent mucus in the trachea.Therefore, several tracheal washings were taken for microbiologic tests by using a commercially available tracheal suction set (Medinorm Medizintechnik GmbH, Quierschied, Germany (Figure 1).A chest radiograph showed a severe and extensive bronchointerstitial pattern with cavernous lesions in both lungs.Nine days after the specimens were taken, cultures for mycobacteria showed growth in the broth-based MGIT 960 system (Becton-Dickinson Microbiology Systems, Sparks, MD).The acid-fast organism that was isolated was identified as MTBC by the AccuProbe TB assay (Gen-Probe Inc., San Diego, CA).Since the tiger had stopped eating and his condition had dramatically deteriorated, the animal was euthanized and

Source: Emerging infectious diseases

DOI: 10.3201/eid0911.030297