Cat Scratch Disease and Bartonellaceae: The Known, the Unknown and the Curious.

Since the early 1900s, Bartonella species were known only to cause human disease resulting from very restricted geographic (bartonellosis) or environmental influences ("trench fever"). In the 1990s, and in parallel, cat scratch disease and bacillary angiomatosis were definitively linked to Bartonella species. Subsequently, widespread use of modern diagnostic methods revealed the broad ecologic niche of this organism and greatly expanded our knowledge of the epidemiology and clinical presentations associated with this genus. A large number of reservoirs and vectors involved with Bartonella propagation and transmission to humans have been identified; cats and various arthropods remain the most well-studied to date. Though not completely understood, it appears that specific immune-modulated interactions between the infecting species and host-related factors play a major role in the observed breadth of human clinical syndromes associated with Bartonellae, the large differences in immunopathologic features of tissue samples among different syndromes and potentially the varied responses to antimicrobial therapy. Further, the clinical management for cat scratch disease in particular is quite variable among clinicians, reflecting a poor evidence base. No preventive measures have been developed beyond suggestions to avoid at-risk behavior with known vectors.

Bartonella quintana Endocarditis in a Homeless Man with Cat Exposure in San Diego, California.

We report a case of Bartonella quintana endocarditis in a homeless man with congenital bicuspid aortic valve and significant cat exposure living in downtown San Diego, California.

Japanese Macaques (Macaca fuscata) as Natural Reservoir of Bartonella quintana.

Bartonella quintana bacteremia was detected in 6 (13.3%) of 45 wild-caught Japanese macaques (Macaca fuscata). Multilocus sequence typing of the isolates revealed that Japanese macaques were infected with a new and specific B. quintana sequence type. Free-ranging Japanese macaques thus represent another natural reservoir of B. quintana.

Bartonella quintana Aortitis in a Man with AIDS, Diagnosed by Needle Biopsy and 16S rRNA Gene Amplification.

A man with newly diagnosed AIDS presented with months of back pain and fever. Computed tomography (CT) results demonstrated aortitis with periaortic tissue thickening. DNA amplification of biopsy tissue revealed Bartonella quintana, and Bartonella serologies were subsequently noted to be positive. The patient improved with prolonged doxycycline and rifabutin treatment. This case illustrates how molecular techniques are increasingly important in diagnosing Bartonella infections.

Genetic diversity of Bartonella quintana in macaques suggests zoonotic origin of trench fever.

Bartonella quintana is a bacterium that causes a broad spectrum of diseases in humans including trench fever. Humans were previously considered to be the primary, if not the only, reservoir hosts for B. quintana. To identify the animal reservoir and extend our understanding of the ecological and evolutionary history of B. quintana, we examined blood samples from macaques and performed multilocus sequence typing (MLST) analysis. We demonstrated the prevalence of B. quintana infection was common in macaques from main primate centres in mainland China. Overall, 18.0% (59/328) of rhesus macaques and 12.7% (39/308) of cynomolgus macaques were found to be infected with B. quintana by blood culture and/or polymerase chain reaction. The infection was more frequently identified in juvenile and young monkeys compared with adult animals. In contrast with the relatively low level of sequence divergence of B. quintana reported in humans, our investigation revealed much higher genetic diversity in nonhuman primates. We identified 44 new nucleotide variable sites and 14 novel sequence types (STs) among the B. quintana isolates by MLST analysis. Some STs were found only in cynomolgus macaques, while some others were detected only in rhesus macaques, suggesting evidence of host-cospeciation, which were further confirmed by phylogenetic analysis and Splits decomposition analysis. Our findings suggest that trench fever may primarily be a zoonotic disease with macaques as the natural hosts.

Prosthetic valve endocarditis caused by Bartonella quintana in a patient during immunosuppressive therapies for collagen vascular diseases.

Bartonella quintana, known to cause various clinical symptoms, is increasingly recognized as one important cause of culture-negative endocarditis. We report a case of infectious endocarditis with B. quintana on the prosthetic valve, accompanied by proteinase 3-antineutrophil cytoplasmic antibody-positive collagen vascular disease-like symptoms 1 year earlier.

[Bartonella infection in hematological practice].

AIM: To characterize the clinical and histological features of Bartonella infection in patients asking for hematological advice and to assess the significance of serological and molecular methods for the diagnosis of this infection. MATERIALS AND METHODS: The case histories of 747 patients asking for advice at the Hematology Research Cancer, Russian Academy of Medical Sciences, for lymphadenopaphy were retrospectively studied. The study included 10 patients in whom Bartonella infection could be suspected. For verification of the diagnosis, the authors conducted a serological study of the patients' sera and a molecular study of archival paraffined lymph node biopsy specimens. RESULTS: The study showed it possible to make a retrospective diagnosis of cat-scratch disease (CSD) by polymerase chain reaction (PCR) used in the study of archival lymph node biopsy specimens and stained preparations. CONCLUSION: CSD should be suspected when a patient has sustained lymphadenopathy and a respective epidemiological history (feline contact). Bartonella infection should be diagnosed on the basis of a dynamic serological study and, if possible, PCR of cells from biopsy specimens of lymph nodes or the lesion developed at the site of Bartonella penetration into the human body (primary affect).

Bacillary angiomatosis and other Bartonella species infections.

Infections with organisms of the genus Bartonella, for many years important only in South and Central America, have assumed significance in developing countries, especially in conjunction with the advent of the pandemic of the human immunodeficiency virus infection. New molecular and culture techniques have determined that these organisms cause new diseases such as bacillary angiomatosis as well as diseases the etiology of which have been unknown such as cat scratch disease. In this article, the microbiology, pathogenesis, histopathology and clinical manifestations of diseases caused by these organisms are discussed.

[Bacillary angiomatosis related to Rochalimaea quintana. Anatomoclinical and ultrastructural study of cutaneous localizations in AIDS]. / Angiomatose bacillaire liée à Rochalimaea quintana. Etude anatomoclinique et ultrastructurale de localisations cutanées au cours d'un SIDA.

We report a case of bacillary angiomatosis in a 53-year-old homosexual man with acquired immunodeficiency syndrome (AIDS). Pathological and bacteriological studies of cutaneous nodules led to the identification of a rickettsia: Rochalimaea quintana. This observation prompted us to relate the clinical presentation of cutaneous and visceral forms of this disease. Histopathological patterns are also considered. They usually consist in a lobular proliferation of capillaries with plump and sometimes epithelioid endothelial cells. Polymorphonuclear cells, histiocytes and necrotic areas may be present. The most characteristic feature is the presence of interstitial, granular and amorphous clusters of bacteria. Diagnostic problems can be raised with Kaposi's angiosarcoma which can be associated with bacillary angiomatosis. Two types of Rochalimaea have so far been isolated in this disease i.e., R. henselae which is the most frequently involved, and R. quintana. The usefulness of making such a diagnosis resides in the sensitivity of bacillary angiomatosis to antibiotics, emphasing the need to carefully look for the presence of bacterial clusters when atypical angioproliferative lesion appears in patients with AIDS.