Granulomatous hepatitis due to Bartonella henselae infection in an immunocompetent patient

<p>Abstract</p> <p>Background</p> <p><it>Bartonella henselae </it>(<it>B. henselae</it>) is considered a rare cause of granulomatous hepatitis. Due to the fastidious growth characteristics of the bacteria, the limited sensitivity of histopathological stains, and the non-specific histological findings on liver biopsy, the diagnosis of hepatic bartonellosis can be difficult to establish. Furthermore, the optimal treatment of established hepatic bartonellosis remains controversial.</p> <p>Case presentation</p> <p>We present a case of hepatic bartonellosis in an immunocompetent woman who presented with right upper quadrant pain and a five cm right hepatic lobe mass on CT scan. The patient underwent a right hepatic lobectomy. Surgical pathology revealed florid necrotizing granulomatous hepatitis, favoring an infectious etiology. Despite extensive histological and serological evaluation a definitive diagnosis was not established initially. Thirteen months after initial presentation, hepatic bartonellosis was diagnosed by PCR studies from surgically excised liver tissue. Interestingly, the hepatic granulomas persisted and <it>Bartonella henselae </it>was isolated from the patient's enriched blood culture after several courses of antibiotic therapy.</p> <p>Conclusion</p> <p>The diagnosis of hepatic bartonellosis is exceedingly difficult to establish and requires a high degree of clinical suspicion. Recently developed, PCR-based approaches may be required in select patients to make the diagnosis. The optimal antimicrobial therapy for hepatic bartonellosis has not been established, and close follow-up is needed to ensure successful eradication of the infection.</p

Comparative microbiological features of Bartonella henselae infection in a dog with fever of unknown origin and granulomatous lymphadenitis

International audienceWe report the first documented case of Bartonella henselae infection in a dog from France and the first isolation of B. henselae from a dog with fever of unknown origin. This observation contributes to the "One Health" concept focusing on zoonotic pathogens emerging from companion animals. A 1-year-old female German shepherd dog was referred for evaluation of fever of unknown origin of 1 month duration. Diagnostic investigations confirmed diffuse pyogranulomatous lymphadenitis. The dog became afebrile, and lymph node size normalized in response to a 6-week course of doxycycline. Retrospectively, Bartonella DNA was amplified from an EDTA-anticoagulated blood sample obtained before antimicrobial therapy, with the gtlA fragment sharing 99 % identity with the 350-bp gtlA fragment of the B. henselae Houston-1 strain. The same strain was isolated in the blood of three healthy cats from the household. Two months after discontinuation of doxycycline, the dog experienced a febrile relapse. Bartonella DNA was again amplified from blood prior to and immediately after administration of a 6-week course azithromycin therapy. However, without administration of additional medications, PCR was negative 9 months after azithromycin therapy and the dog remains clinically healthy 12 months following the second course of antibiotics. The medical management of this case raises several clinically relevant comparative infectious disease issues, including the extent to which Bartonella spp. contribute to fever of unknown origin and pyogranulomatous inflammatory diseases in dogs and humans, and the potential of doxycycline and azithromycin treatment failures. The possibility that dogs could constitute an underestimated reservoir for B. henselae transmission to people is also discussed