Jane E. Koehler

Bio: Jane E. Koehler is an academic researcher from University of California, San Francisco. The author has contributed to research in topics: Bartonella henselae & Bartonella. The author has an hindex of 38, co-authored 83 publications receiving 7067 citations. Previous affiliations of Jane E. Koehler include Centers for Disease Control and Prevention & University of California, Berkeley.

Experimental transmission of Bartonella henselae by the cat flea.

Abstract: Bartonella henselae is an emerging bacterial pathogen, causing cat scratch disease and bacillary angiomatosis. Cats bacteremic with B. henselae constitute a large reservoir from which humans become infected. Prevention of human infection depends on elucidation of the natural history and means of feline infection. We studied 47 cattery cats in a private home for 12 months to determine the longitudinal prevalence of B. henselae bacteremia, the prevalence of B. henselae in the fleas infesting these cats, and whether B. henselae is transmitted experimentally to cats via fleas. Vector-mediated transmission of B.henselae isolates was evaluated by removing fleas from the naturally bacteremic, flea-infested cattery cats and transferring these fleas to specific-pathogen-free (SPF) kittens housed in a controlled, arthropod-free University Animal Facility. B. henselae bacteremia was detected in 89% of the 47 naturally infected cattery cats. A total of 132 fleas were removed from cats whose blood was simultaneously cultured during different seasons and were tested individually for the presence of B. henselae DNA by PCR. B. henselae DNA was detected in 34% of 132 fleas, with seasonal variation, but without an association between the presence or the level of bacteremia in the corresponding cat. Cat fleas removed from bacteremic cattery cats transmitted B. henselae to five SPF kittens in two separate experiments; however, control SPF kittens housed with highly bacteremic kittens in the absence of fleas did not become infected. These data demonstrate that the cat flea readily transmits B. henselae to cats. Control of feline infestation with this arthropod vector may provide an important strategy for the prevention of infection of both humans and cats.

Recommendations for Treatment of Human Infections Caused by Bartonella Species

Abstract: Members of the genus Bartonella are facultative intracellular bacteria belonging to the alpha 2 subgroup of the class Proteobacteria and are phylogenetically closely related to Brucella species (15, 73). Until 1993, only three diseases were known to be caused by Bartonella species: Carrion's disease (Bartonella bacilliformis), trench fever (Bartonella quintana), and cat scratch disease (CSD; Bartonella henselae). The genus now comprises B. bacilliformis, species of the former genera Rochalimea and Grahamella (14, 18), and additional, recently described species (Table ​(Table1).1). In mammals, each Bartonella species is highly adapted to its reservoir host; the bacteria can persist in the bloodstream of the host as the result of intraerythrocytic parasitism (49). Intraerythrocytic localization of B. henselae has been demonstrated in cat erythrocytes (88), and B. bacilliformis bacilli have been observed within erythrocytes during the acute phase of Carrion's disease (Oroya fever) (88). Bartonellae also have a tropism for endothelial cells, and intracellular B. henselae can be identified in endothelial cells infected in vitro (28), although intraendothelial cell bacilli have not been identified in vivo. TABLE 1. Epidemiological and clinical data for species of the genus Bartonella Bartonella species cause long-recognized diseases, such as Carrion's disease, trench fever, and CSD, and more recently recognized diseases, such as bacillary angiomatosis (BA), peliosis hepatis (PH), chronic bacteremia, endocarditis, chronic lymphadenopathy, and neurological disorders (Table ​(Table2)2) (73). A remarkable feature of the genus Bartonella is the ability of a single species to cause either acute or chronic infection and either vascular proliferative or suppurative manifestations. TABLE 2. Human diseases caused by Bartonella spp. The pathological response to infection with Bartonella spp. varies substantially with the status of the host immune system. Indeed, infection with the same Bartonella species (e.g., B. henselae) can result in a focal suppurative reaction (CSD in immunocompetent patients), a multifocal angioproliferative response (BA in immunocompromised patients), endovascular multiplication of the bacteria (endocarditis), or an exaggerated inflammatory response without evidence of bacteria in patient tissues (meningoencephalitis) (86). Some of the diseases due to Bartonella species can resolve spontaneously without treatment, but in other cases, the disease is fatal without antibiotic treatment and/or surgery. The clinical situations are so different that a single treatment for all Bartonella-related diseases has not been identified, and the approach to treatment must be adapted to each species and clinical situation (49). Moreover, the database of clinical studies with a standard case definition, culture confirmation, rigidly defined disease outcomes, and patients with similar host defenses is very limited. Thus, case reports with a very limited number of subjects often serve to dictate therapy. The objective of this minireview is to summarize the antibiotic treatment recommendations for the different infections caused by Bartonella species. We have compiled the in vitro antibiotic susceptibility data and our knowledge of the in vivo efficacies of antibiotics for each clinical manifestation, and finally, we have summarized and ranked our treatment recommendations according to the Infectious Diseases Society of America (IDSA) practice guidelines (see Table ​Table5)5) (51). TABLE 5. System for ranking recommendations in clinical guidelines recommended by IDSAa

Rochalimaea henselae Infection A New Zoonosis With the Domestic Cat as Reservoir

Abstract: Objective. —To determine the reservoir and vector(s) forRochalimaea henselae, a causative agent of bacillary angiomatosis (BA) and cat scratch disease, and to estimate the percentage of domestic cats withR henselaebacteremia in the Greater San Francisco Bay Region of Northern California. Design. —Hospital-based survey of patients diagnosed with BA who also had significant exposure to at least one pet cat, as well as a convenience sampling of pet or impounded cats for prevalence ofRochalimaeabacteremia. Setting. —Community and university hospitals and clinics; veterinary clinics treating privately owned or impounded cats. Patients. —Patients with or without human immunodeficiency virus infection, with biopsy-confirmed BA, who had prolonged exposure to pet cats prior to developing BA. Main Outcome Measures. —Cultures and laboratory studies were performed on blood drawn from pet cats associated with patients with BA. TheRochalimaeaspecies infecting pet cats and fleas and causing the BA lesions in human contacts of these cats was identified by culture, polymerase chain reaction—restriction fragment length polymorphism analysis, and DNA sequencing. The presence ofR henselaebacteremia in pet cats was documented, and predictor variables for culture positivity were evaluated. Results. —Four patients diagnosed with BA who had prolonged contact with seven pet cats were identified. TheRochalimaeaspecies causing BA lesions in these patients was determined to beR henselae. The seven pet cats were found to be bacteremic withR henselae; this bacterium was also detected in fleas taken from an infected cat by both direct culture and polymerase chain reaction. Blood samples were cultured from pet and impounded cats (N=61) in the Greater San Francisco Bay Region, andR henselaewas isolated from 41% (25/61) of these cats. Conclusion. —We have documented that the domestic cat serves as a major persistent reservoir forR henselae, with prolonged, asymptomatic bacteremia from which humans, especially the immunocompromised, may acquire potentially serious infections. Antibiotic treatment of infected cats and control of flea infestation are potential strategies for decreasing human exposure toR henselae. (JAMA. 1994;271:531-535)

Isolation of Rochalimaea species from cutaneous and osseous lesions of bacillary angiomatosis.

Abstract: Background. Bacillary angiomatosis is characterized by vascular lesions, which occur usually in patients infected with the human immunodeficiency virus (HIV). A newly described gram-negative organism, Rochalimaea henselae, has been associated with cutaneous bacillary angiomatosis, but no organism has been isolated and cultivated directly from cutaneous tissue. Methods. We used two methods to isolate the infecting bacterium from four HIV-infected patients with cutaneous lesions suggestive of bacillary angiomatosis: cultivation with eukaryotic tissue-culture monolayers and direct plating of homogenized tissue onto agar. The patients' blood was cultured with the lysis—centrifugation method. Isolates recovered from skin and blood were identified by sequencing all or part of the 16S ribosomal RNA gene amplified with the polymerase chain reaction. Results. R. quintana, historically known as the agent of trench fever, was isolated from cutaneous lesions in three patients, after tissue homogenates were c...

Foodborne Illness Acquired in the United States—Major Pathogens

Abstract: Estimates of foodborne illness can be used to direct food safety policy and interventions. We used data from active and passive surveillance and other sources to estimate that each year 31 major pathogens acquired in the United States caused 9.4 million episodes of foodborne illness (90% credible interval [CrI] 6.6–12.7 million), 55,961 hospitalizations (90% CrI 39,534–75,741), and 1,351 deaths (90% CrI 712–2,268). Most (58%) illnesses were caused by norovirus, followed by nontyphoidal Salmonella spp. (11%), Clostridium perfringens (10%), and Campylobacter spp. (9%). Leading causes of hospitalization were nontyphoidal Salmonella spp. (35%), norovirus (26%), Campylobacter spp. (15%), and Toxoplasma gondii (8%). Leading causes of death were nontyphoidal Salmonella spp. (28%), T. gondii (24%), Listeria monocytogenes (19%), and norovirus (11%). These estimates cannot be compared with prior (1999) estimates to assess trends because different methods were used. Additional data and more refined methods can improve future estimates.

2015 ESC Guidelines for the management of infective endocarditis

Abstract: 3D : three-dimensional AIDS : acquired immune deficiency syndrome b.i.d. : bis in die (twice daily) BCNIE : blood culture-negative infective endocarditis CDRIE : cardiac device-related infective endocarditis CHD : congenital heart disease CIED : cardiac implantable electronic device

Clinical Practice Guideline for the Use of Antimicrobial Agents in Neutropenic Patients with Cancer: 2010 Update by the Infectious Diseases Society of America

Abstract: This document updates and expands the initial Infectious Diseases Society of America (IDSA) Fever and Neutropenia Guideline that was published in 1997 and first updated in 2002. It is intended as a guide for the use of antimicrobial agents in managing patients with cancer who experience chemotherapy-induced fever and neutropenia. Recent advances in antimicrobial drug development and technology, clinical trial results, and extensive clinical experience have informed the approaches and recommendations herein. Because the previous iteration of this guideline in 2002, we have a developed a clearer definition of which populations of patients with cancer may benefit most from antibiotic, antifungal, and antiviral prophylaxis. Furthermore, categorizing neutropenic patients as being at high risk or low risk for infection according to presenting signs and symptoms, underlying cancer, type of therapy, and medical comorbidities has become essential to the treatment algorithm. Risk stratification is a recommended starting point for managing patients with fever and neutropenia. In addition, earlier detection of invasive fungal infections has led to debate regarding optimal use of empirical or preemptive antifungal therapy, although algorithms are still evolving. What has not changed is the indication for immediate empirical antibiotic therapy. It remains true that all patients who present with fever and neutropenia should be treated swiftly and broadly with antibiotics to treat both gram-positive and gram-negative pathogens. Finally, we note that all Panel members are from institutions in the United States or Canada; thus, these guidelines were developed in the context of North American practices. Some recommendations may not be as applicable outside of North America, in areas where differences in available antibiotics, in the predominant pathogens, and/or in health care-associated economic conditions exist. Regardless of venue, clinical vigilance and immediate treatment are the universal keys to managing neutropenic patients with fever and/or infection.

Infective Endocarditis in Adults: Diagnosis, Antimicrobial Therapy, and Management of Complications A Scientific Statement for Healthcare Professionals From the American Heart Association

Abstract: Background— Infective endocarditis is a potentially lethal disease that has undergone major changes in both host and pathogen. The epidemiology of infective endocarditis has become more complex wit...