Dialister pneumosintes associated with human brain abscesses.

In this report, we review two cases of brain infection due to Dialister pneumosintes in previously healthy patients. The bacterium was isolated from the first patient by blood culture and directly from a brain abscess in the second patient. In both cases, the infection was suspected to be of nasopharyngeal or dental origin. The patients had favorable outcomes following surgical debridement and antibiotic treatment. After in vitro amplification and partial sequencing of the 16S rRNA gene, two strains were classified as D. pneumosintes. However, traditional biochemical tests were not sufficient to identify the bacteria. In addition to causing periodontal and opportunistic infections, D. pneumosintes, contained in mixed flora, may behave as a clinically important pathogen, especially in the brain. In addition to phenotypic characterization, 16S rRNA partial sequencing was used to identify D. pneumosintes definitively.

Cat-scratch disease neuroretinitis diagnosed by a polymerase chain reaction approach.

PURPOSE: To assess the value of polymerase chain reaction in the diagnosis of cat-scratch disease neuroretinitis without conclusive serology. METHODS: Interventional case report. A 13-year-old girl developed a right neuroretinitis 2 months after a cat scratch. Despite the lack of accompanying features, an infection by Bartonella henselae was suspected and a systemic check-up was performed. RESULTS: Serologic results excluded other proposed origins but were insufficient in making the diagnosis because of low B. henselae specific IgG level in serum. A polymerase chain reaction analysis for B. henselae DNA in a small axillary lymphadenopathy aspirate enabled us to achieve a definitive diagnosis of cat-scratch disease. CONCLUSION: Polymerase chain reaction is a valuable method of diagnosing cat-scratch disease when serology is considered negative or borderline.

Kinetics of Bartonella birtlesii infection in experimentally infected mice and pathogenic effect on reproductive functions.

The kinetics of infection and the pathogenic effects on the reproductive function of laboratory mice infected with Bartonella birtlesii recovered from an Apodemus species are described. B. birtlesii infection, as determined by bacteremia, occurred in BALB/c mice inoculated intravenously. Inoculation with a low-dose inoculum (1.5 x 10(3) CFU) induced bacteremia in only 75% of the mice compared to all of the mice inoculated with higher doses (> or =1.5 x 10(4)). Mice became bacteremic for at least 5 weeks (range, 5 to 8 weeks) with a peak ranging from 2 x 10(3) to 10(5) CFU/ml of blood. The bacteremia level was significantly higher in virgin females than in males but the duration of bacteremia was similar. In mice infected before pregnancy (n = 20), fetal loss was evaluated by enumerating resorption and fetal death on day 18 of gestation. The fetal death and resorption percentage of infected mice was 36.3% versus 14.5% for controls (P < 0.0001). Fetal suffering was evaluated by weighing viable fetuses. The weight of viable fetuses was significantly lower for infected mice than for uninfected mice (P < 0.0002). Transplacental transmission of Bartonella was demonstrated since 76% of the fetal resorptions tested was culture positive for B. birtlesii. The histopathological analysis of the placentas of infected mice showed vascular lesions in the maternal placenta, which could explain the reproductive disorders observed. BALB/c mice appeared to be a useful model for studying Bartonella infection. This study provides the first evidence of reproductive disorders in mice experimentally infected with a Bartonella strain originating from a wild rodent.

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

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.

Bartonella birtlesii sp. nov., isolated from small mammals (Apodemus spp.).

Three strains isolated from Apodemus spp. were similar to Bartonella species on the basis of phenotypic characteristics. Futhermore, genotypic analysis based on sequence analysis of the 16S rRNA and gltA genes and on DNA-DNA hybridization showed that the three isolates represented a distinct and new species of Bartonella. The name Bartonella birtlesii is proposed for the new species. The type strain of B. birtlesii sp. nov. is IBS 325T (= CIP 106294T = CCUG 44360T).

Bartonella tribocorum sp. nov., a new Bartonella species isolated from the blood of wild rats.

Two Bartonella strains from blood of two wild rats (Rattus norvegicus) living in a rural environment were isolated. These strains were distinct from all previously known Bartonella species based on phenotypic and genotypic characteristics. This new species is distinguished by its trypsin-like activity, the absence of the ability to hydrolyse proline and tributyrin, its 16S rRNA and citrate synthase gene sequences and by whole-DNA hybridization data. This new species, for which the name Bartonella tribocorum sp. nov. is proposed, seems to be genetically related to Bartonella elizabethae, an agent isolated in a case of human endocarditis. The type strain of Bartonella tribocorum sp. nov. is IBS 506T (CIP 105476T).

Ditiocarb: decomposition in aqueous solution and effect of the volatile product on its pharmacological use.

The kinetic profile for the decomposition of ditiocarb sodium salt in aqueous solution was achieved with UV-visible absorption spectrometry. The kinetic profile indicates that the decomposition reaction is hydrogen ion-catalyzed over the entire 4-10 pH range and enables the determination of the value of the acid-base equilibrium constant (Ka = 4.0.10(-4) at 5 degrees C). Decomposition of ditiocarb produces volatile carbon disulfide, exclusive of hydrogen sulfide, as shown with electrochemical methods. This feature is of interest from a toxicological point of view.