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Y Piemont

Publications and source records attributed to Y Piemont.

At least 19 recordsLinked to original sources

Comparison of microbiological results of needle puncture vs. superficial swab in infected diabetic foot ulcer with osteomyelitis.

AIM: To study prospectively two methods for the bacteriological diagnosis of osteomyelitis related to diabetic foot ulcer: needle puncture performed across normal skin surrounding the foot ulcer and superficial swabbing of the ulcer. PATIENTS AND METHODS: Diabetic patients with a foot ulcer complicated by bone or joint infection, as detected by X-ray imaging, were included in the study. Ulcer swabbing and needle puncture were performed in each patient. To reach the tissue nearest the bone surface, needle puncture was guided by X-ray imaging and the drop of fluid obtained by aspiration was used for both aerobic and anaerobic bacterial culture. RESULTS: Twenty-one diabetic patients were included. The mean number of microorganisms isolated by needle puncture was significantly lower compared with that obtained by superficial swabbing: 1.09 vs. 2.04 (P < 0.02). Three bacterial species were isolated by needle puncture only in one patient while three or more bacterial isolates were obtained by superficial swabbing in six patients. No bacterial isolate was detected in five patients by needle puncture and in two patients by superficial swabbing. Staphylococcus aureus accounted for 70% of cases (seven patients) when a single bacterial species was obtained by needle puncture. After needle puncture, no wound complication or infection was observed. CONCLUSION: Culture of samples obtained by needle puncture revealed one or two bacterial isolates in two-thirds of diabetic patients with osteomyelitis following foot ulcer. Given the lack of complications, this invasive diagnostic technique should be considered for deep direct sampling in diabetic patients with osteomyelitis related to foot ulcer when surgical debridement is contraindicated or delayed.

Adult↗

Detection of Chlamydia trachomatis DNA using MagNA Pure DNA extraction and Cobas Amplicor CT/NG amplification.

The automated MagNA Pure DNA extraction method for Chlamydia trachomatis was compared with the manual Cobas Amplicor protocol using 100 microL of input sample volume from 964 specimens. Agreement between protocols was 96.1%. The automated extraction method had a sensitivity of 99% and a specificity of 100%. Amplification inhibition observed after manual preparation of samples (3.8%) was not apparent following automated extraction. Using 200 microL of sample in the automated extraction process lowered the detection limit without raising the inhibition rate. Furthermore, the automated extraction method halved the hands-on time required for the procedure.

Automation↗

Peripartum bacteremias due to Leptotrichia amnionii and Sneathia sanguinegens, rare causes of fever during and after delivery.

We report three cases of delivery and postpartum bacteremia due to unusual anaerobic bacteria in healthy young women. Leptotrichia amnionii bacteremia occurred during delivery in two mothers and was associated with fetal distress during labor. Conversely, Sneathia sanguinegens bacteremia occurred postpartum, 2 days after delivery, without consequence for the neonate.

Adult↗

Epidemiology of Bartonella infection in domestic cats in France.

Blood samples were collected between February and June 1996 from a convenience sample of 436 domestic French cats living in Paris and its environs and were tested for Bartonella bacteremia and seropositivity. Seventy-two cats (16.5%) were Bartonella bacteremic, of which 36 cats (50%) were infected with Bartonella henselae type II (B.h. II) only, 15 cats (21%) were infected with Bartonella clarridgeiae (B.c.) only, and 11 cats (15%) were infected with B. henselae type I (B.h. I) only. Eight cats (11%) were co-infected with B. henselae and B. clarridgeiae (B.h. II/B.c.: five cats; B.h. I/B.c.: three cats). Two cats (2.8%) were concurrently bacteremic with B. henselae types I and II. Risk factors associated with bacteremia included ownership for <6months (prevalence ratio (PR)=1.80; 95% confidence interval (CI)=1.13-2.85), adoption from the pound or found as a stray (PR=1.67, 95% CI=1.05-2.65), and cohabitation with one or more cats (PR=1.60, 95% CI=1.01-2.53). Bartonella antibodies to either B. henselae or B. clarridgeiae were detected in 179 cats (41.1%). Risk factors associated with seroposivity paralleled those for bacteremia, except for lack of association with time of ownership. Prevalence ratios of bacteremic or seropositive cats increased with the number of cats per household (p=0.02). The lack of antibodies to B. henselae or B. clarridgeiae was highly predictive of the absence of bacteremia (predictive value of a negative test=97.3%). Multiple logistic regression analysis indicated that bacteremia, after adjustment for age and flea infestation, and positive serology, after adjustment for age, were associated with origin of adoption and number of cats in the household. Flea infestation was associated with positive serology.

Animals↗

Treatment resistant Lyme arthritis caused by Borrelia garinii.

Lyme arthritis is caused in Europe by three main pathogenic species of Borrelia burgdorferi sensu lato: Borrelia burgdorferi sensu stricto, Borrelia garinii, and Borrelia afzelii. Because few synovial samples have yet been analysed by species-specific DNA amplification methods, further studies are needed to define the spectra of clinical manifestations associated with these different species. Two cases of treatment resistant Lyme arthritis are reported here, in which DNA amplification of the flagellin gene followed by dot-blot hybridisation in the synovial fluid identified B garinii as the causative agent. Clinical and biological data did not differ from the usual descriptions of Lyme arthritis, but as the recently reported molecular mimicry between OspA and hLFA1 is not applicable to B garinii, the pathogenesis of the present cases remains unclear. Future studies should aim at assessing the role of B garinii in European Lyme arthritis and its possible pathogenic and therapeutic consequences.

Adult↗

Coyotes (Canis latrans) as the reservoir for a human pathogenic Bartonella sp.: molecular epidemiology of Bartonella vinsonii subsp. berkhoffii infection in coyotes from central coastal California.

Bartonella vinsonii subsp. berkhoffii was originally isolated from a dog suffering infectious endocarditis and was recently identified as a zoonotic agent causing human endocarditis. Following the coyote bite of a child who developed clinical signs compatible with Bartonella infection in Santa Clara County, Calif., this epidemiological study was conducted. Among 109 coyotes (Canis latrans) from central coastal California, 31 animals (28%) were found to be bacteremic with B. vinsonii subsp. berkhoffii and 83 animals (76%) had B. vinsonii subsp. berkhoffii antibodies. These findings suggest these animals could be the wildlife reservoir of B. vinsonii subsp. berkhoffii. PCR-restriction fragment length polymorphism (PCR-RFLP) analysis of the gltA and 16S rRNA genes for these 31 isolates yielded similar profiles that were identical to those of B. vinsonii subsp. berkhoffii. Partial sequencing of the gltA and 16S rRNA genes, respectively, indicated 99.5 and 100% homology between the coyote isolate and B. vinsonii subsp. berkhoffii (ATCC 51672). PCR-RFLP analysis of the 16S-23S intergenic spacer region showed the existence of two different strain profiles, as has been reported in dogs. Six (19%) of 31 Bartonella bacteremic coyotes exhibited the strain profile that was identified in the type strain of a canine endocarditis case (B. vinsonii subsp. berkhoffii ATCC 51672). The other 25 bacteremic coyotes were infected with a strain that was similar to the strains isolated from healthy dogs. Based on whole bacterial genome analysis by pulsed-field gel electrophoresis (PFGE) with SmaI restriction endonuclease, there was more diversity in fingerprints for the coyote isolates, which had at least 10 major variants compared to the two variants described for domestic dog isolates from the eastern United States. By PFGE analysis, three Bartonella bacteremic coyotes were infected by a strain identical to the one isolated from three healthy dog carriers. Further studies are necessary to elucidate the mode of transmission of B. vinsonii subsp. berkhoffii, especially to identify potential vectors, and to determine how humans become infected.

Animals↗

Oxacillin susceptibility testing of staphylococci directly from Bactec Plus blood cultures by the BBL Crystal MRSA ID system.

The BBL Crystal MRSA ID test (Becton Dickinson) was applied directly to blood culture vials containing clusters of gram-positive cocci. The sensitivity and specificity of the test were 84 and 100% and 54 and 100% for vials containing Staphylococcus aureus and coagulase-negative staphylococci, respectively. This test is a reliable method for direct detection of methicillin resistance in positive blood culture vials when S. aureus is identified in parallel by rapid identification procedures.

Blood↗

Prevalence of Bartonella henselae and Bartonella clarridgeiae in stray cats.

The aim of the present work was to determine by blood culture the prevalence of blood infection with Bartonella species in a well-defined, European, urban stray cat population. Therefore, 94 stray cats were trapped from 10 cat colonies. Blood samples of these cats were cultured on both blood agar and liquid medium in order to raise the likelihood of bacterial detection. Fifty blood samples (53%) gave a positive culture result for Bartonella species. Isolate identification was performed by sequencing the first 430 bases of the 16S ribosomal DNA. Three types of sequences were thus obtained. The first type (17 isolates; 34%) was identical to that of B. henselae Houston-1 and the corresponding strains were referred as B. henselae type I. The second sequence type (18 isolates; 36%) was identical to that initially described as "BA-TF," and the corresponding strains were referred to as B. henselae type II. The third sequence type (15 isolates; 30%) was identical to that of the Bartonella clarridgeiae type strain (ATCC 51734). Our study points out the major role of stray cats as a reservoir of Bartonella spp. which can be transmitted to pet cats and, consequently, to humans. The study also highlights the high prevalence of B. clarridgeiae (16%) in the blood of stray cats.

Animals↗

Coinfection with Bartonella clarridgeiae and Bartonella henselae and with different Bartonella henselae strains in domestic cats.

Bartonella clarridgeiae and several strains of Bartonella henselae, the agent of cat scratch disease, with variations in the 16S rRNA gene have been found to infect the blood of cats. An epidemiologic study of Bartonella infection in domestic French cats revealed that of 436 cats sampled, 5 cats (1.1%) were coinfected with B. henselae and B. clarridgeiae and 2 cats (0.5%) were coinfected with two strains of B. henselae with variations in the 16S rRNA gene, B. henselae type I and type II. In an indirect immunofluorescence assay, coinfected cats tested positive for both Bartonella species at titers of > or = 128. Identification of the colonies was achieved by preformed enzyme analysis, PCR-restriction fragment length polymorphism analysis of the citrate synthase gene, and 16S rRNA gene sequencing. Colony size differences in mixed culture allowed differentiation of the Bartonella species. The coinfection of cats with two Bartonella species or variants of the same species raises concern about the possibility of dual infection in humans. The development of a polyvalent vaccine targeted against the most pathogenic or invasive strains may be a means of protecting cats and man from infection.

Animals↗

Frequency of isolation of Staphylococcus intermedius from humans.

We collected 3,397 consecutive isolates of coagulase-positive staphylococci from various specimens of hospitalized patients. All were retrospectively classified as Staphylococcus aureus, except two which were identified as S. intermedius: one isolated from the nasal flora of a healthy carrier and the other isolated from pleural fluid, probably as a sample contaminant.

Aged↗

[Tsukamurella infections. Review of the literature apropos of a case].

The genus Tsukamurella belongs to the family Nocardiaceae, and is an environmental saprophyte. The type species is Tsukamurella paurometabola. Its microbiological identification and differentiation from the other species containing mycolic acids can be difficult. There has been a few cases of human infections reported, usually in patients with special conditions, such as chronic lung pathology, immuno-suppression (leukemia, solid tumors, maybe HIV-infection) or the long-term use of indwelling catheters. The treatment of choice, despite the lack of adequate guidelines, is an antibiotherapy combining a beta-lactam and an aminoglycoside; catheter removal appears to be essential for cure.

AIDS-Related Opportunistic Infections↗

[Isolation of Helicobacter pylori: necessity of control of transport conditions].

The aim of the study was the influence of transport conditions of antrum biopsies on the diagnostis of Helicobacter pylori infection by mean of bacteriological methods. We compare bacteriological to anatomopathological methods of Helicobacter pylori infection during two periods which differed by the transport conditions for antrum biopsies. During the first period (P1), 57 specimens were carried to the laboratory at room temperature and physiological serum immersion was inconstant. During the second period (P2), 56 specimens were all correctly immerged into 5 ml of physiological serum, in a 15 mm diameter tube which was vertically maintained in ice. Anatomopathological methods were considered as the reference method for the diagnostic of Helicobacter pylori infection. The sensibility of bacteriological culture was increased from 59% (P1) to 84% (P2) (p < 0.05) when specificity was unchanged. Furthermore sensibility of bacteriological direct examination was increased from 41% (P1) to 61% (P2). Complete biopsy immersion and ice transport of samples appear as necessary conditions for the optimal diagnostic of Helicobacter infections by mean of bacteriological methods.

Bacteriological Techniques↗

Diagnostic value of the indirect immunofluorescence assay in cat scratch disease with Bartonella henselae and Afipia felis antigens.

Serum samples from 35 cat scratch disease (CSD) patients, 180 control patients (123 without lymph node enlargement and 57 with lymph node enlargement not evoking CSD), and 102 nonpatient subjects (35 with cat contact and 67 without cat contact) were tested by semiquantitative indirect immunofluorescence assay for the presence of antibodies directed to Afipia felis (ATCC 53690T) or Bartonella henselae (ATCC 49882T). The CSD group had statistically higher antibody titers against B. henselae than the control groups (P < 10(-5)), whereas no difference in A. felis antibody titers was evidenced among all groups tested. Among the 317 serum samples studied, the three with high A. felis antibody titers ( > or = 64) also had high antibody titers against other alpha-2 proteobacteria. The value of the indirect immunofluorescence assay with B. henselae antigen for the diagnosis of CSD was as follows: for a cutoff of 32, sensitivity was 0.80, specificity was 0.85, and the likelihood ratio was 5.1; for a cutoff of 64, the likelihood ratio was 12.1. In summary, in France, CSD is associated with high antibody titers against B. henselae, as previously described in the United States. However, the causes for B. henselae seronegativity in CSD patients and those for high antibody titers outside the typical nosological frame of CSD still have to be identified.

Adult↗