Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “BARTONELLA”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,243 records · Page 69Linked to original sources
PubMed2005

Impact of a molecular approach to improve the microbiological diagnosis of infective heart valve endocarditis.

BACKGROUND: Even today, infective endocarditis (IE) remains a severe and potentially fatal disease demanding sophisticated diagnostic strategies for detection of the causative microorganisms. Despite the use of appropriate laboratory techniques, classic microbiological diagnostics are characterized by a high rate of negative results. METHODS AND RESULTS: Broad-range polymerase chain reaction (PCR) targeting bacterial and fungal rDNA followed by direct sequencing was applied to excised heart valves (n=52) collected from 51 patients with suspected infectious endocarditis and from 16 patients without any signs of IE during an 18-month period. The sensitivity, specificity, and the positive and negative predictive values for the bacterial broad-range PCR were 41.2%, 100.0%, 100.0%, and 34.8%, respectively, compared with 7.8%, 93.7%, 80.0%, and 24.2% for culture and 11.8%, 100.0%, 100.0%, and 26.2% for Gram staining. Without exception, database analyses allowed identification up to the (sub)species level comprising streptococcal (n=13), staphylococcal (n=4), enterococcal (n=2), and other signature sequences such as Bartonella quintana and Nocardia paucivorans. Fungal ribosomal sequences were not amplified. All valve tissues of the reference group were negative for both PCR and conventional methods, except one sample that was contaminated by molds. CONCLUSIONS: Culture-independent molecular methods substantially improve the diagnostic outcome of microbiological examination of excised heart valves. Importantly, this was true not only for fastidious, slow-growing, and/or nonculturable microorganisms but also for easy-to-culture pathogens such as streptococci and staphylococci. Both patient management and empiric antibiotic therapy of IE are likely to benefit from improved knowledge of the spectrum of pathogens now causing IE.

Adolescent↗
PubMed2006

Indoleamine 2,3-dioxygenase-expressing dendritic cells form suppurative granulomas following Listeria monocytogenes infection.

Control of pathogens by formation of abscesses and granulomas is a major strategy of the innate immune system, especially when effector mechanisms of adaptive immunity are insufficient. We show in human listeriosis that DCs expressing indoleamine 2,3-dioxygenase (IDO), together with macrophages, are major cellular components of suppurative granulomas in vivo. Induction of IDO by DCs is a cell-autonomous response to Listeria monocytogenes infection and was also observed in other granulomatous infections with intracellular bacteria, such as Bartonella henselae. Reporting on our use of the clinically applied anti-TNF-alpha antibody infliximab, we further demonstrate in vitro that IDO induction is TNF-alpha dependent. Repression of IDO therefore might result in exacerbation of granulomatous diseases observed during anti-TNF-alpha therapy. These findings place IDO(+) DCs not only at the intersection of innate and adaptive immunity but also at the forefront of bacterial containment in granulomatous infections.

Antigens, CD↗
PubMed2006

The reach of the genome signature in prokaryotes.

BACKGROUND: With the increased availability of sequenced genomes there have been several initiatives to infer evolutionary relationships by whole genome characteristics. One of these studies suggested good congruence between genome synteny, shared gene content, 16S ribosomal DNA identity, codon usage and the genome signature in prokaryotes. Here we rigorously test the phylogenetic signal of the genome signature, which consists of the genome-specific relative frequencies of dinucleotides, on 334 sequenced prokaryotic genome sequences. RESULTS: Intrageneric comparisons show that in general the genomic dissimilarity scores are higher than in intraspecific comparisons, in accordance with the suggested phylogenetic signal of the genome signature. Exceptions to this trend, (Bartonella spp., Bordetella spp., Salmonella spp. and Yersinia spp.), which have low average intrageneric genomic dissimilarity scores, suggest that members of these genera might be considered the same species. On the other hand, high genomic dissimilarity values for intraspecific analyses suggest that in some cases (e.g. Prochlorococcus marinus, Pseudomonas fluorescens, Buchnera aphidicola and Rhodopseudomonas palustris) different strains from the same species may actually represent different species. Comparing 16S rDNA identity with genomic dissimilarity values corroborates the previously suggested trend in phylogenetic signal, albeit that the dissimilarity values only provide low resolution. CONCLUSION: The genome signature has a distinct phylogenetic signal, independent of individual genetic marker genes. A reliable phylogenetic clustering cannot be based on dissimilarity values alone, as bootstrapping is not possible for this parameter. It can however be used to support or refute a given phylogeny and resulting taxonomy.

Bacteria↗
PubMed2005

Signature proteins that are distinctive of alpha proteobacteria.

BACKGROUND: The alpha (alpha) proteobacteria, a very large and diverse group, are presently characterized solely on the basis of 16S rRNA trees, with no known molecular characteristic that is unique to this group. The genomes of three alpha-proteobacteria, Rickettsia prowazekii (RP), Caulobacter crescentus (CC) and Bartonella quintana (BQ), were analyzed in order to search for proteins that are unique to this group. RESULTS: Blast analyses of protein sequences from the above genomes have led to the identification of 61 proteins which are distinctive characteristics of alpha-proteobacteria and are generally not found in any other bacteria. These alpha-proteobacterial signature proteins are generally of hypothetical functions and they can be classified as follows: (i) Six proteins (CC2102, CC3292, CC3319, CC1887, CC1725 and CC1365) which are uniquely present in most sequenced alpha-proteobacterial genomes; (ii) Ten proteins (CC1211, CC1886, CC2245, CC3470, CC0520, CC0365, CC0366, CC1977, CC3010 and CC0100) which are present in all alpha-proteobacteria except the Rickettsiales; (iii) Five proteins (CC2345, CC3115, CC3401, CC3467 and CC1021) not found in the intracellular bacteria belonging to the order Rickettsiales and the Bartonellaceae family; (iv) Four proteins (CC1652, CC2247, CC3295 and CC1035) that are absent from various Rickettsiales as well as Rhodobacterales; (v) Three proteins (RP104, RP105 and RP106) that are unique to the order Rickettsiales and four proteins (RP766, RP192, RP030 and RP187) which are specific for the Rickettsiaceae family; (vi) Six proteins (BQ00140, BQ00720, BQ03880, BQ12030, BQ07670 and BQ11900) which are specific to the order Rhizobiales; (vii) Four proteins (BQ01660, BQ02450, BQ03770 and BQ13470) which are specific for the order Rhizobiales excluding the family Bradyrhizobiaceae; (viii) Nine proteins (BQ12190, BQ11460, BQ11450, BQ11430, BQ11380, BQ11160, BQ11120, BQ11100 and BQ11030 which are distinctive of the Bartonellaceae family;(ix) Six proteins (CC0189, CC0569, CC0331, CC0349, CC2323 and CC2637) which show sporadic distribution in alpha-proteobacteria, (x) Four proteins (CC2585, CC0226, CC2790 and RP382) in which lateral gene transfers are indicated to have occurred between alpha-proteobacteria and a limited number of other bacteria. CONCLUSION: The identified proteins provide novel means for defining and identifying the alpha-proteobacteria and many of its subgroups in clear molecular terms and in understanding the evolution of this group of species. These signature proteins, together with the large number of alpha-proteobacteria specific indels that have recently been identified http://www.bacterialphylogeny.com, provide evidence that all species from this diverse group share many unifying and distinctive characteristics. Functional studies on these proteins should prove very helpful in the identification of such characteristics.

Alphaproteobacteria↗
PubMed2004

Cat-scratch disease: historic, clinical, and pathologic perspectives.

Cat-scratch disease (CSD) initially was described in 1931, but the etiologic agent (Bartonella henselae) was not elucidated until decades later. This disease is the most common cause of chronic lymphadenopathy among children and adolescents, characteristically manifesting as subacute regional lymphadenitis with an associated inoculation site due to a cat scratch or bite, often accompanied by fever. The hallmark histologic lesion is granulomatous inflammation with a central stellate microabscess. Numerous atypical manifestations of CSD have been described, and these often lack the characteristic superficial lymphadenopathy and inoculation site papule. These atypical forms may be misdiagnosed initially as other infectious processes or neoplasms. We present a review of the history and epidemiologic features of CSD, describe common and unusual clinicopathologic manifestations, and discuss current diagnostic modalities.

Animals↗
PubMed2007

An immunohistochemical and polymerase chain reaction evaluation of feline plasmacytic pododermatitis.

Sections of 14 skin biopsies of cats with plasmacytic pododermatitis and a clinical follow-up of 12-36 months were stained with a polyclonal anti-Mycobacterium bovis (Bacille Calmette-Guerin = BCG) antibody cross-reactive to a broad spectrum of fungi and bacteria. All sections were negative for organisms within the actual footpad tissue with the anti-BCG antibody stains. Polymerase chain reaction (PCR) assays that amplify the DNA of Bartonella spp., Ehrlichia spp., Anaplasma phagocytophilum, Chlamydophila felis, Mycoplasma spp., Toxoplasma gondii, and feline herpesvirus 1 (FHV-1) were applied to tissue digests. DNA of those pathogens assessed was not amplified from tissue.

Animals↗
PubMed2002

Treatment and prevention of infective endocarditis.

The paper presents the most recent recommendations for the treatment and prevention of infective endocarditis (IE). The treatment of IE is complex and requires close collaboration among specialists in infectious diseases, cardiology, cardiac surgery and microbiology. The mainstay of medical treatment is antibiotic therapy. Theoretical considerations regarding vegetations and antibiotics have practical consequences on the route and modalities of administration of antibiotics and on the techniques used to monitor treatment. The choice of antibiotics depends on the microorganism (streptococci, enterococci, staphylococci, HACEK group [Haemophilus sp., Actinobacillus sp., Cardiobacterium sp., Eikenella sp. and Kingella sp.], Coxiella, Brucella, Legionella, Bartonella, fungi) and on whether IE occurs on native or prosthetic valves. Treatment of IE with negative blood cultures is particularly difficult. Cardiac surgery is often needed during the bacteriologically active period (in ~50% of patients). The decision to intervene and the optimal timing of the intervention requires careful consideration of multiple potential risks: the haemodynamic risk, the infectious risk, the risk due to cardiac lesions, the risk due to extracardiac complications and the risk due to the location of infective endocarditis. Even though the efficacy of antibiotic prophylaxis of IE is not completely proven, it is recommended for selected patients who undergo an at-risk procedure. Lists of cardiac conditions and of medical procedures at risk are presented; specific antibiotic prophylactic regimens for dental and upper respiratory tract procedures in out-patients, procedures under general anaesthesia and urological and GI procedures are outlined.

Anti-Bacterial Agents↗
PubMed2004

Infective endocarditis: a review of the best treatment options.

Despite significant advances in antimicrobial therapy and an enhanced ability to diagnose and treat complications, infective endocarditis is still associated with substantial morbidity and mortality today, and its incidence has not decreased over the past decades. This apparent paradox may be explained by a progressive change in risk factors, leading to an evolution in its epidemiological and clinical features. In fact, new risk factors for endocarditis have emerged, such as intravenous drug abuse, diffusion of heart surgery procedures and prosthetic valve implantation, atherosclerotic valve disease in elderly patients, and nosocomial disease. Recently identified microorganisms (including Bartonella spp., Abiotrophia defectiva, and the HACEK group of bacteria [including Haemophilus spp., Actinobacillus spp., Cardiobacterium hominis, Eikenella corrodens and Kingella kingae]) are sometimes the cause of culture-negative endocarditis, and emerging resistant bacteria (such as methicillin- or vancomycin-resistant Staphylococci and vancomycin-resistant Enterococci) are becoming a new challenge for conventional antibiotic therapy. New therapeutic approaches need to be developed for the treatment of infective endocarditis caused by drug-resistant Gram-positive cocci, and some antimicrobial compounds recently introduced in clinical practice (such as streptogramins and oxazolidinones) may be an effective alternative, but further clinical studies are needed in order to confirm their effectiveness and safety. This review should help redefine the best therapeutic and preventive strategies against infective endocarditis.

Anti-Bacterial Agents↗
PubMed1998

Cat scratch disease presenting with peripheral facial nerve paralysis.

Acquired peripheral facial nerve paralysis is a relatively common disorder that affects both children and adults. The most frequent nontrauma-related etiologies in otherwise neurologically intact patients are idiopathic (Bell's palsy) and infectious, which includes otitis media, herpes zoster, Lyme disease, herpes simplex virus, Epstein-Barr virus, and Mycoplasma pneumoniae. Cat scratch disease (CSD) is typically a subacute, regional lymphadenitis caused by Bartonella henselae that is seen in children and young adults. CSD most often has a benign, self-limited course. However, 11% of CSD patients may present atypically, most commonly with Perinaud's oculoglandular syndrome or acute encephalopathy. We present a child with the first reported case of acute facial nerve paralysis in serologically proven CSD with typical lymphadenitis.

Cat-Scratch Disease↗
PubMed2002

Acute disseminated encephalomyelitis in children.

OBJECTIVE: To describe the epidemiologic, clinical, neuroimaging, and laboratory features; treatment; and outcome in a cohort of children with acute disseminated encephalomyelitis (ADEM). METHODS: A 6-year retrospective chart review of children with the diagnosis of ADEM was conducted. RESULTS: Eighteen cases were identified. Sixteen patients (88%) presented in either winter or spring. Thirteen children (72%) had a recent upper respiratory tract illness. Patients presented most often with motor deficits (77%) and secondly with altered consciousness (45%). Spinal fluid abnormalities occurred in 70%. Despite rigorous microbiologic testing, a definite microbiologic diagnosis was established only in 1 child with Epstein-Barr virus disease and probable or possible diagnoses in 3 children with Bartonella henselae, Mycoplasma pneumoniae, or rotavirus disease. Brain magnetic resonance imaging identified lesions in the cerebral cortex in 80%, in subcortical white matter in 93%, in periventricular white matter in 60%, in deep gray matter in 47%, and in brainstem in 47% of patients. Eleven patients (61%) were treated with corticosteroids, and 2 were treated with intravenous immunoglobulins. All patients survived. Three patients (17%) had long-term neurologic sequelae. CONCLUSIONS: Epidemiologic evidence from this study suggests an infectious cause for ADEM. The agent is most likely a difficult-to-diagnose winter/spring respiratory virus. Magnetic resonance imaging was the neuroimaging study of choice for establishing the diagnosis and for following the course of the disease. Prognosis for survival and outcome was excellent. Recurrent episodes of ADEM must be differentiated from multiple sclerosis.

Acute Disease↗
PubMed2005

Lyme disease: point/counterpoint.

Lyme disease represents a growing public health threat. The controversial science and politics of Lyme disease have created barriers to reliable diagnosis and effective treatment of this protean illness. Two major clinical hurdles are the absence of a therapeutic end point in treating Borrelia burgdorferi, the spirochetal agent of Lyme disease, and the presence of tickborne coinfections with organisms such as Babesia, Anaplasma, Ehrlichia and Bartonella that may complicate the course of the disease. From a pathophysiologic standpoint, the affinity of Borrelia burgdorferi for multiple cell types and the presence of nonreplicating forms of the Lyme disease spirochete have contributed to persistent infection and failure of simple antibiotic regimens. Newer approaches to the treatment of Lyme disease should take into account its clinical complexity in coinfected patients and the possible need for prolonged combination therapy in patients with persistent symptoms of this potentially debilitating illness. The optimal antibiotic regimen for chronic Lyme disease remains to be determined.

Anti-Bacterial Agents↗
PubMed2004

Organismal effects of pesticide exposure on meadow voles (Microtus pennsylvanicus) living in golf course ecosystems: developmental instability, clinical hematology, body condition, and blood parasitology.

This is the second of two articles reporting the results of a nonlethal biomonitoring study that quantified the effects of pesticide exposure on meadow voles (Microtus pennsylvanicus) living in golf course ecosystems of the Ottawa/Gatineau region (ON and PQ, Canada, respectively). In the present article, we describe results of measurements regarding developmental instability (e.g., fluctuating asymmetry), congenital birth defects (e.g., skeletal terata), clinical hematology (e.g., differential counts), general body condition (e.g., body mass-length relationships), and blood parasite load (Trypanosoma sp. and Bartonella spp.). Voles were captured during the year 2001 to 2003 at six golf courses and two reference sites. Once voles were fully sedated using isoflurane, blood was collected, radiographs taken, and morphometric measurements recorded. Three animals from each course were euthanized to determine body burdens of historically used organochlorine (OC) and metal-based pesticides. Exposure to in-use pesticides was determined from detailed golf course pesticide-use records. None of the endpoints measured was significantly related to body burdens of OC pesticides and metals historically used, nor did any endpoint significantly vary among capture sites in relation to total pesticide application to the capture site or to the number of days since the last application of pesticide. Based on these findings, it appears that voles from golf courses were no less healthy than their conspecifics from reference sites.

Animals↗
PubMedDate not supplied

[Bacterial infections in patients infected by HIV].

Individuals infected by the human immuno deficiency are more prone to suffering certain bacterial infections in the course of their clinical evolution. The agents involved in these infections are: Streptococcus pneumoniae, Haemophilus influenzae, Pseudomonas aeruginosa, Salmonella spp and Campylobacter spp, which occasion an increase in morbidity and mortality. With a lower frequency, but with an equal morbidity and mortality, infections have been found caused by Rhodococcus equi, Nocardia spp and Bartonella spp. Even though all of them account for a selective impairment of immunodeficiency in one way or another, their incidence varies. Other factors such as degree of immuno suppression, habits, social and geographic living environment could be important. In general, there is a lack of chemoprophylactic strategies for their prevention. Early diagnosis and correct treatment could have important advantages for the quality of life and survival of these patients

English Abstract↗
PubMed1997

Pathogenetic role of phagocytic abnormalities in human virus immunodeficiency infection: possible therapeutical approaches. A review.

Polymorphonuclear cells (PMN) and monocytes/macrophages (M/M) represent the first defence line against invading microorganisms. Both phagocytic cell functions are precociously compromised in human immunodeficiency virus (HIV)-infected subjects, thus leading to infectious and neurological complications in the late stages of disease. Among intracellular pathogens, emerging bacteria such as Bartonella henselae and Rhodococcus equi can cause peculiar clinical pictures, i.e. the bacillary parenchimal angiomatosis and a classical pyogranulomatous broncopneumonia, respectively. On the other hand, overproduction of proinflammatory cytokines (CKs) and, in particular, tumor necrosis factor-alpha under HIV or lipopolysaccharide stimulation may cause neural damage in terms of demyelination and subsequent development of acquired immunodeficiency syndrome (AIDS) dementia complex. Some therapeutical attempts have been made with colony stimulating factors in order to increase the number and potentiate the function of PMN and M/M. On the other hand, the use of drugs able to reduce exaggerated release of CKs by M/M is suggested in AIDS patients in order to prevent a further aggravation of the clinical condition.

HIV Infections↗
PubMedDate not supplied

Flea-borne rickettsioses: ecologic considerations.

Ecologic and economic factors, as well as changes in human behavior, have resulted in the emergence of new and the reemergence of existing but forgotten infectious diseases during the past 20 years. Flea-borne disease organisms (e.g., Yersinia pestis, Rickettsia typhi, R. felis, and Bartonella henselae) are widely distributed throughout the world in endemic-disease foci, where components of the enzootic cycle are present. However, flea-borne diseases could reemerge in epidemic form because of changes in vector-host ecology due to environmental and human behavior modification. The changing ecology of murine typhus in southern California and Texas over the past 30 years is a good example of urban and suburban expansion affecting infectious disease outbreaks. In these areas, the classic rat-flea-rat cycle of R. typhi has been replaced by a peridomestic animal cycle involving, e.g., free-ranging cats, dogs, and opossums and their fleas. In addition to the vector-host components of the murine typhus cycle, we have uncovered a second typhuslike rickettsia, R. felis. This agent was identified from the blood of a hospitalized febrile patient and from opossums and their fleas. We reviewed the ecology of R. typhi and R. felis and present recent data relevant to the vector biology, immunology, and molecular characterization and phylogeny of flea-borne rickettsioses.

Animals↗
PubMed2003

Comparative molecular and microbiologic diagnosis of bacterial endocarditis.

Sequencing of 16S rDNA, and of sodAint and rpoBint in some cases, was applied to DNA from heart valves of 46 patients (36 with definite and 10 with possible endocarditis). Sequence-based identifications were compared with those obtained with conventional methods. Among the 36 definite cases, 30 had positive blood cultures and 6 had negative cultures. Among the 30 positive cases, sequencing of 16S rDNA permitted identification of species (18), genus (8), or neither (4); sodAint and rpoBint sequencing was necessary for species identification in 8 cases. Species identifications were identical in only 61.5%, when conventional techniques and DNA sequencing were used. In five of the six blood culture-negative endocarditis cases, sequencing identified Bartonella quintana (3), B. henselae (1), and Streptococcus gallolyticus (1). Our results demonstrate a clear benefit of molecular identification, particularly in cases of blood culture-negative endocarditis and of possible endocarditis, to confirm or invalidate the diagnosis. Moreover, in 19.4% of the definite cases, the improvement in species identification by sequencing led to improved patient management.

Adult↗
PubMed2004

Emerging issues in infective endocarditis.

Infective endocarditis, a serious infection of the endocardium of the heart, particularly the heart valves, is associated with a high degree of illness and death. It generally occurs in patients with altered and abnormal heart architecture, in combination with exposure to bacteria through trauma and other potentially high-risk activities involving transient bacteremia. Knowledge about the origins of endocarditis stems from the work of Fernel in the early 1500s, and yet this infection still presents physicians with major diagnostic and management dilemmas. Endocarditis is caused by a variety of bacteria and fungi, as well as emerging infectious agents, including Tropheryma whiplei, Bartonella spp., and Rickettsia spp. We review the evolution of endocarditis and compare its progression with discoveries in microbiology, science, and medicine.

Endocarditis, Bacterial↗
PubMed2004

Acinetobacter baumannii in human body louse.

While we were isolating Bartonella quintana from body lice, 40 Acinetobacter baumannii strains were also isolated and genotyped. One clone was unique and the other was ampicillin susceptible. A. baumannii DNA was later detected in 21% of 622 lice collected worldwide. These findings show an A. baumannii epidemic in human body lice.

Acinetobacter baumannii↗