Infectious endocarditis by Bartonella species: report of two cases / Endocarditis infecciosa por Bartonella: descripción de dos casos en Chile

ABSTRACT Infectious endocarditis (IE) by Bartonella species is an emerging problem worldwide. We report two cases of native valve Bartonella-associated IE events, both affecting adult male patients with a history of alcohol abuse and a low socioeconomic status. Admissions were due to pancytopenia and bleeding in one case and embolic stroke in the other. Blood cultures were negative and IgG indirect immunofluorescence assays (IFA) were positive for B. henselae/B. quintana in high titers (1/16,384-1/16,384, and 1/32,768 -1/16,384, respectively). Cases were classified as definitive IE events according to modified Duke criteria due to the presence of valve vegetations with at least three minor criteria. One patient required aortic mechanical valve replacement and survived, and the other died after a massive hemorrhagic transformation of his stroke. PCR amplification and sequencing of the 16S ribosomal bacterial DNA from a valve tissue sample obtained at surgery in the patient who survived, confirmed B. quintana as the etiological agent. Bartonella-associated IE is an emerging problem in Chile, present in disadvantaged populations. It should be suspected in patients with culture-negative IE. IFA does not discriminate between B. henselae and B. quintana infection, but high titers suggest IE. Complementary PCR techniques may help to elucidate the final causative agent.

La endocarditis infecciosa(EI) asociada a Bartonella es un problema emergente a nivel mundial. Publicamos los 2 primeros casos de EI en válvula nativa asociados a Bartonella en Chile, los que afectaron a pacientes masculinos con historia de consumo de alcohol y bajos ingresos. La hospitalización fue provocada por pancitopenia y hemorragias en un caso y por un evento cerebrovascular en el otro. Se solicitó serología para Bartonella por inmunofluorescencia indirecta (IFI) para ampliar el estudio ante hemocultivos negativos y en ambos casos se reportaron resultados intensamente positivos para B. henselae y B. quintana1/16.384-1/16.384 y 1/32.768 -1/16.384, respectivamente). Los casos se clasificaron como eventos definitivos de EI según los criterios modificados de Duke debido a la presencia de vegetaciones valvulares con al menos 3 criterios menores. Un paciente requirió reemplazo valvular aórtico y sobrevivió, y el otro falleció tras una transformación hemorrágica masiva del infarto cerebral. La amplificación del ADN ribosomal 16S por RCP y posterior secuenciación de una muestra de tejido valvular confirmó la presencia de B. quintana. La EI por Bartonella sp. es un problema emergente en Chile, probablemente asociada a poblaciones desfavorecidas, la que debe ser sospechada en pacientes con cultivos negativos. La IFI no permite discriminar infecciones por B. henselae o B. quintana pero los títulos altos sugieren EI. Técnicas complementarias por RCP pueden ayudar a dilucidar el diagnóstico.

Bartonella presenting as branch retinal artery occlusion in a child.

Branch retinal artery occlusion (BRAO) is rare in children. Bartonella is a known cause of branch retinal artery occlusion in adults, but it is typically not considered in the differential diagnosis for pediatric BRAO. We present the case of a 12-year old boy with a BRAO caused by a Bartonella henselae infection. This is the youngest such case reported in the literature. Although rare, Bartonella infection may be an important and underrecognized cause of pediatric BRAO.

Infectious endocarditis by Bartonella species. Report of two cases.

Infectious endocarditis (IE) by Bartonella species is an emerging problem worldwide. We report two cases of native valve Bartonella-associated IE events, both affecting adult male patients with a history of alcohol abuse and a low socioeconomic status. Admissions were due to pancytopenia and bleeding in one case and embolic stroke in the other. Blood cultures were negative and IgG indirect immunofluorescence assays (IFA) were positive for B. henselae/B. quintana in high titers (1/16,384-1/16,384, and 1/32,768 -1/16,384, respectively). Cases were classified as definitive IE events according to modified Duke criteria due to the presence of valve vegetations with at least three minor criteria. One patient required aortic mechanical valve replacement and survived, and the other died after a massive hemorrhagic transformation of his stroke. PCR amplification and sequencing of the 16S ribosomal bacterial DNA from a valve tissue sample obtained at surgery in the patient who survived, confirmed B. quintana as the etiological agent. Bartonella-associated IE is an emerging problem in Chile, present in disadvantaged populations. It should be suspected in patients with culture-negative IE. IFA does not discriminate between B. henselae and B. quintana infection, but high titers suggest IE. Complementary PCR techniques may help to elucidate the final causative agent.

Role of Whole-Body MR with DWIBS in child's Bartonellosis.

Cat-scratch disease (CSD) is a zoonosis in children, result of infection by Bartonella henselae, a gram-negative bacillus. Infection is generally characterized by regional and self-limited lymphadenopathy after exposure to a scratch or bite from a cat. Rarely, B. henselae is cause of fever of unknown origin (FUO), with dissemination to various organs, most often involving the reticuloendothelial system (liver, spleen, bone marrow), mimicking an inflammatory rather than a lymphoproliferative disease. Whole-body Magnetic Resonance Imaging (WBMRI), in association with diffusion-weighted imaging (DWIBS), allows a comprehensive evaluation of pediatric patients, without the risks inherent to ionizing radiation. It is a rapid and sensitive method for detecting and monitoring multifocal lesions such as proliferative or inflammatory and infectious processes. We report a case of systemic CDS in an immunocompetent young boy with fever of unknown origin, without history of cat contact, investigated by WBMRI.

Expressive aphasia as a presentation of encephalitis with Bartonella henselae infection in an immunocompetent adult.

OBJECTIVE: To show the first clinically reported case of Cat Scratch Disease (CSD) presenting as a focal neurologic deficit in an immunocompetent adult. PATIENT: 59-year-old male with a history of a previous stroke. RESULTS: Examination showed an expressive aphasia, word substitution errors, and impaired repetition. A head CT and MRI showed no acute changes. The EEG findings were non-focal and did not show any epileptiform activity. The patient had a history of contact with stray kittens and previous axillary lymphadenopathy. Bartonella henselae serology titers were IgG positive 1:1024 (< 64) and IgM positive 1:20 (< 16). After antibiotic administration, the patient's symptoms and aphasia resolved. CONCLUSIONS: Focal presentations concerning for stroke or partial seizure activity may have underlying infectious etiology. We recommend consideration of CSD in the differential diagnosis of any adult with a history of lymphadenopathy, fever, and recent contact with a cat who presents with neurologic complications.

Cat-scratch disease presenting as a solitary tumour in the breast: report of three cases.

Cat-scratch disease (CSD) may appear as a solitary mass in the breast and give the impression of a breast carcinoma. In this case, further clinical and laboratory investigation is required to rule out malignancy. We present three cases of CSD of the breast in women of 64, 31 and 61 years old. Each presented with enlarged lymph-nodes in the breast, which were clinically mistaken for solitary tumours. In the first two patients, the mammography was negative. The third patient had a mammogram which indicated a well-defined solid mass in the parenchyma without calcifications. We discuss the clinical, histological and histochemical findings, analyze the differential diagnosis and review the literature.

[Bartonella endocarditis on native valves. Apropos of 2 cases]. / Endocardite a Bartonella sur valve native. A propos de 2 cas.

The authors report two cases of Bartonella endocarditis in native valves. The first case was a 15 year old North African Girl who lived in poor social conditions and was admitted to hospital with pyrexia and congestive heart failure. Investigations revealed massive mitral regurgitation due to ruptured chordae tendinae, vegetations on the pulmonary valve with severe pulmonary hypertension due to persistent ductus arteriosus. After antibiotic therapy, the patient underwent surgery for mitral valve replacement, pulmonary valvuloplasty and closure of the patent ductus arteriosus. The second case was a 39 year old man with no fixed abode with a history of alcoholism who presented with a recurrent ischaemic stroke in a context of infection with a murmur of aortic regurgitation. Echocardiography showed a vegetation on the aortic valve with grade III/IV regurgitation requiring aortic valve replacement with a homograft after antibiotic therapy. The aetiological diagnosis was made a posteriori by the finding of high antibody titres and specific genetic amplification of Bartonella. In patients with negative blood cultures, Bartonella infection should be looked for systematically especially in those living under poor social conditions. The practical diagnostic investigation of endocarditis with negative blood cultures is reviewed.

Bartonella-associated infections in HIV-infected patients.

AIDS: Two species of the gram-negative bacilli Bartonella, B. henselae and B. quintana, cause disease in HIV-infected patients. If untreated, infection can be fatal. Manifestations include bacillary angiomatosis (BA), bacillary peliosis hepatis (BP), bacteremia, or a combination of these. BA and BP present as lesions, but bacteremia may be subacute and persist for months without diagnosis. Additionally, patients may acquire cat scratch disease (CSD), but this is more common in immunocompetent patients. BA lesions are usually vascular, friable, and bleed profusely when traumatized. They may be confused with Kaposi's sarcoma (KS), pyogenic granuloma, lymphoma and various subcutaneous tumors and infections. Lesions may affect almost any organ, and appear as angiomatous papules, dry scaling lesions, subcutaneous nodules, cellulitic plaques or deep, highly vascularized, soft tissue masses. Patients may have osseus BA lesions (frequently affecting the long bones); hepatic and/or splenic lesions; bacteremia; or endocarditis. To diagnose infection, lesions should be biopsied and examined. Hematoxylin and eosin staining reveal histopathologic changes; darkly staining organisms are evident after Warthin-Starry silver staining; and electron microscopy allows visualization of the bacillus. An indirect immunofluorescence antibody test (IFA) detects bartonella-specific IgG antibodies. Treatment with erythromycin for at least three months is recommended, or with doxycycline if erythromycin is not well-tolerated. Severely ill patients should receive IV doxycycline with either gentamicin or rifampin for at least four months. To prevent infection, HIV-infected people should avoid traumatic cat contact and exposure to the body louse.^ieng