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Featured researches published by Anna Sander.


International Journal of Systematic and Evolutionary Microbiology | 2001

Bartonella schoenbuchii sp. nov., isolated from the blood of wild roe deer.

Christoph Dehio; Christa Lanz; Rainer Pohl; Peter Behrens; Delphine Bermond; Yves Piemont; Klaus Pelz; Anna Sander

The genus Bartonella comprises two human-specific pathogens and a growing number of zoonotic or animal-specific species. Domesticated as well as wild mammals can serve as reservoir hosts for the zoonotic agents and transmission to humans may occur by blood sucking arthropods or by direct blood to blood contact. Humans may come into intimate contact with free-ranging mammals during hunting, especially during evisceration with bare hands, when accidental blood to blood contact frequently occurs. The objective of this work was to determine the presence and the polymorphism of Bartonella strains in wild roe deer (Capreolus capreolus) as the most widely spread game in Western Europe. We report the isolation of four Bartonella strains from the blood of five roe deer. These strains carry polar flagella similar to Bartonella bacilliformis and Bartonella clarridgeiae. Based on their phenotypic and genotypic characteristics, three of the four roe deer isolates were different and they were all distinct from previously described Bartonella species. They can be distinguished from each other and from other Bartonella species by their protein profile, ERIC-PCR pattern, 16S rRNA and citrate synthase (gitA) gene sequences, as well as by whole DNA-DNA hybridization. In spite of their considerable heterogeneity, all four strains fulfil the criteria for belonging to a single new species. The name Bartonella schoenbuchii is proposed for this new species. The type strain R1T of Bartonella schoenbuchii has been deposited in the National Collection of Type Cultures as NCTC 13165T and the Deutsche Sammlung von Mikroorganismen und Zellkulturen as DSM 13525T.


European Journal of Clinical Microbiology & Infectious Diseases | 2001

Serodiagnosis of cat scratch disease: response to Bartonella henselae in children and a review of diagnostic methods.

Anna Sander; Reinhard Berner; Michael Ruess

Abstract In this study, sera from 116 children without clinical evidence of cat scratch disease (CSD) and sera from 19 children with CSD were investigated by two different immunofluorescent assays (test A and test B) to evaluate the seroprevalence of Bartonella henselae antibodies in this population. Antibodies against Bartonella henselae were found in noninfected children only in low titers: 13% and 3.5% of serum samples were positive by test A and test B, respectively. IgG titers as determined by test A ranged from 1 : 64 to 1 : 256, whereas test B did not yield titers  1 1 : 64. Of the 19 children with CSD, 7 (37%) and 5 (26%) had low antibody titers (1 : 64–1 : 256) on admission by test A and test B, respectively. In such cases, IgM antibodies against Bartonella henselae and/or a titer increase in the following weeks are required to prove suspected CSD. The results indicate that the seroprevalence of Bartonella henselae antibodies in children without evidence of CSD is low, and that the results may differ depending on the tests being used. Low antibody titers, however, were found not only in healthy children but also among patients with CSD, which could be indicative of the beginning or of the end of an illness. Currently, only few data are available concerning the seroprevalence of antibodies to Bartonella spp. among children. Although children are often affected by CSD, the specificity of most tests has been evaluated by investigating blood donors, who are usually adults. Several different serological tests are used for the diagnosis of CSD, including the immunofluorescence assay, the enzyme-linked immunosorbent assay, and Western blot (WB) analysis. The sensitivities of different IFAs range from 14 to 100%, depending on the antigen used, the cut-off chosen, and the test procedures. The current diagnostic value of different serological tests for diagnosis of CSD is reviewed.


Clinical Infectious Diseases | 2002

Role of Cat-Scratch Disease in Lymphadenopathy in the Head and Neck

Gerd Jürgen Ridder; Carsten Christof Boedeker; Katja Technau-Ihling; Roland Grunow; Anna Sander

Bartonella henselae is the causative agent of cat-scratch disease (CSD), which usually manifests as acute regional lymphadenopathy. The causes of cervical lymphadenopathy, with special regard to CSD, were investigated in a study of 454 patients who presented with unclear masses in the head and neck from January 1997 through January 2001. Sixty-one patients (13.4%) experienced CSD; 54 (11.9%) had primary lymphadenopathy due to other infectious agents, and 41 (9.0%) had lymphadenopathy that occurred in association with primary infections of other organs. For 171 patients (37.7%), the cause of the cervical lymph node enlargement could not be found. B. henselae DNA was detected in extirpated lymph nodes only during the first 6 weeks of lymphadenopathy, which indicates that the results of polymerase chain reaction strongly depend on the duration of illness. CSD should be included in the differential diagnosis of adenopathy in the otorhinolaryngologic patient population, to avoid unnecessary treatment.


Otolaryngology-Head and Neck Surgery | 2005

Spectrum and Management of Deep Neck Space Infections: An 8-Year Experience of 234 Cases

Gerd Jürgen Ridder; Katja Technau-Ihling; Anna Sander; Carsten Christof Boedeker

OBJECTIVE: To study the clinical course and outcome of deep neck infections (DNI), with special emphasis on microbiology and histopathology. STUDY DESIGN: Two hundred thirty-four patients with DNIs were included in this study. Patients with peritonsillar or dental infections, infections arising from salivary glands, as well as subjects with abscesses caused by neck trauma were excluded. METHODS: Clinical analysis of all patients with DNIs who were treated between January 1, 1997 and May 31, 2005 in a single center. RESULTS: In 13 patients, the DNI was the first manifestation of a malignant tumor. In 17 cases, the DNI was associated with cat-scratch disease (CSD). Six patients suffered from tuberculosis, and in another 7, an infected lateral cleft cyst was found. In 176 patients, the origin of DNI remained unclear. CONCLUSIONS: Our results demonstrate that CSD, tuberculosis, and malignant tumors must be considered as possible causes of DNIs. The current study represents one of the largest series of DNIs in the modern medical literature.


Journal of Clinical Microbiology | 2006

Multispacer Typing To Study the Genotypic Distribution of Bartonella henselae Populations

Wenjun Li; Bruno B. Chomel; Soichi Maruyama; Lynn Guptil; Anna Sander; Didier Raoult; Pierre Edouard Fournier

ABSTRACT Bartonella henselae, a worldwide fastidious bacterium, has a feline reservoir and is pathogenic for humans. However, the relationship between human and cat isolates of B. henselae, as well as its population dynamics and geographic heterogeneity, is not fully understood, in part because of the absence of appropriate typing methods. Multilocus sequence typing (MLST), the most discriminatory genotyping method for B. henselae, identified seven genotypes and suggested that human isolates arose from a limited number of cat isolates. Herein, we estimated the discriminatory power of multispacer typing (MST) by studying 126 B. henselae cat isolates from various areas of Europe, Asia, and the United States. We identified the nine most variable intergenic spacers conserved by both B. henselae and Bartonella quintana genomes. By comparing the sequences obtained from these nine spacers for each studied isolate, we identified 39 MST genotypes. The distribution of isolates into MST genotypes matched their phylogenetic organization into four clusters. MST showed that European and Asian isolates were different, in contrast with American isolates, but failed to identify pandemic strains. Our study demonstrated that MST is a powerful method for genotyping B. henselae at the strain level and may serve in studying the population dynamics of this bacterium and understanding the relationships between cat and human isolates. Finally, we provide a free-access MST-Rick online software program (http://ifr48.timone.univ-mrs.fr/MST_BHenselae/mst ) that investigators may use to compare their own MST sequences to our database.


Journal of Clinical Microbiology | 2003

A Serotype V Clone Is Predominant among Erythromycin-Resistant Streptococcus agalactiae Isolates in a Southwestern Region of Germany

Ulrich von Both; Michael Ruess; Urban Mueller; Kirsten Fluegge; Anna Sander; Reinhard Berner

ABSTRACT One hundred ninety-three Streptococcus agalactiae isolates of neonatal origin and 146 isolates from adult women were analyzed for macrolide resistance and investigated for clonality. Among erythromycin-resistant isolates, serotype V turned out to be the most frequent. Comparative pulsed-field gel electrophoresis analysis revealed genetic clustering of resistant strains and predominance of a single clone family within an otherwise heterogeneous serotype V population.


Trends in Microbiology | 1999

Bartonella as emerging pathogens

Christoph Dehio; Anna Sander

cancause vasoproliferative disorderssuch as bacillary angiomatosis(BA) and bacillary peliosis hepati-tis (BPH) in immunocompromisedpatients (reviewed in Ref. 1), andthere is growing awareness thatthese pathogens are also causativeagents of endocarditis in homelesspeople and in patients with chronicalcohol abuse (D. Raoult, MarseilleHospital, France). The spectrumof clinical syndromes that is recog-nized as being caused by


Otolaryngology-Head and Neck Surgery | 2005

Cat-scratch disease: Otolaryngologic manifestations and management

Gerd Jürgen Ridder; Carsten Christof Boedeker; Katja Technau-Ihling; Anna Sander

OBJECTIVE: The bacteria Bartonella henselae has been known as the principal causative agent of cat-scratch disease (CSD) since 1992. It is an important cause of infectious lymphadenopathies in the head and neck. Nevertheless, CSD often remains unrecognized in cases of cervicofacial lymph node enlargement. STUDY DESIGN: Between January 1997 and May 2003, we conducted a prospective clinical study including 721 patients with primarily unclear masses in the head and neck. RESULTS: CSD was diagnosed by serology and molecular investigations in 99 patients (13.7%; median age 33 years). Cervicofacial lymphadenopathy was the most common manifestation. Atypical manifestation of CSD including Parinauds oculoglandular syndrome, swelling of the parotid gland and erythema nodosum were diagnosed in 8.1%, 8.1%, and 2.0% of cases, respectively. CONCLUSIONS: Our results demonstrate that CSD is a major cause of enlarged cervicofacial lymph nodes and should therefore be included in the differential diagnosis of lymphadenopathy in the head and neck region.


Journal of Bacteriology | 2003

Hemin Binding, Functional Expression, and Complementation Analysis of Pap 31 from Bartonella henselae

Rainer Zimmermann; Volkhard A. J. Kempf; Emile Schiltz; Karin Oberle; Anna Sander

Growth of Bartonella henselae is strongly heme dependent, and B. henselae is unable to synthesize heme itself. At least five outer membrane-associated proteins from B. henselae bind hemin, including the 31-kDa protein designated Pap31. The gene of this protein was heterologously expressed in Escherichia coli M15(pREP4) and detected with monoclonal antibodies in the outer membrane fraction. Complementation of the hemA-deficient mutant E. coli K-12 EB53 (aroB tsx malT hemA) with pap31 demonstrated that this protein is involved in heme acquisition and may be an important virulence factor in the pathogenesis of B. henselae.


Scandinavian Journal of Infectious Diseases | 2000

Antimicrobial susceptibility patterns of Streptococcus agalactiae in a German university hospital.

Michael Ruess; Urban Müller; Anna Sander; Reinhard Berner

Group B streptococci (GBS) are the major cause of neonatal sepsis and meningitis. GBS infection in neonates is usually treated with a combination of penicillin and gentamicin. According to consensus guidelines, pregnant women at risk receive intrapartum prophylaxis with either ampicillin or penicillin or, in case of allergy, with erythromycin or clindamycin. We investigated the susceptibility patterns of 190 GBS strains from neonates isolated from 1993-1999 and 150 GBS strains collected from adult women in 1997 and 1999. All isolates were susceptible to penicillin, ampicillin and cefotaxime. Erythromycin resistance among all isolates from neonates and from adult women in 1997 was 4.7% and 6%, respectively. In contrast, 12% of the isolates from adult women in 1999 were resistant to erythromycin and 7% were resistant to clindamycin. These findings show an increasing macrolide resistance in recent GBS strains and indicate the need for further surveillance.Group B streptococci (GBS) are the major cause of neonatal sepsis and meningitis. GBS infection in neonates is usually treated with a combination of penicillin and gentamicin. According to consensus guidelines, pregnant women at risk receive intrapartum prophylaxis with either ampicillin or penicillin or, in case of allergy, with erythromycin or clindamycin. We investigated the susceptibility patterns of 190 GBS strains from neonates isolated from 1993-1999 and 150 GBS strains collected from adult women in 1997 and 1999. All isolates were susceptible to penicillin, ampicillin and cefotaxime. Erythromycin resistance among all isolates from neonates and from adult women in 1997 was 4.7% and 6%, respectively. In contrast, 12% of the isolates from adult women in 1999 were resistant to erythromycin and 7% were resistant to clindamycin. These findings show an increasing macrolide resistance in recent GBS strains and indicate the need for further surveillance.

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Michael Ruess

Boston Children's Hospital

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Reinhard Berner

Boston Children's Hospital

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Bernhard Richter

University Medical Center Freiburg

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