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P E Fournier

Publications and source records attributed to P E Fournier.

At least 19 recordsLinked to original sources
PubMed2004

First isolation of Rickettsia conorii from humans in the Trakya (European) region of Turkey.

In the Trakya region of Turkey, located in the European part of the country, presumptive cases of Mediterranean spotted fever have been diagnosed and treated every summer since the beginning of the 1990s. The aim of this prospective study was to isolate and identify the rickettsial strains from blood samples of 11 patients and from skin biopsies of 10 of these 11 patients with the diagnosis of spotted fever in the Trakya region of Turkey in 2003. Immunofluorescence assay was performed with acute-phase and convalescent-phase serum samples of 11 patients. All patients had significant antibody titers against spotted fever group rickettsiae. Rickettsia conorii was isolated from the skin biopsies of three of ten patients and was also demonstrated by polymerase chain reaction in skin biopsies of nine of ten patients. In southeastern Europe, the Balkan Peninsula (including the Trakya region of Turkey) is an area where arthropods are endemic and where new arthropod-borne infections can be detected.

Adult↗
PubMed2004

Real-time PCR for universal antibiotic susceptibility testing.

OBJECTIVES: Determination of bacterial antimicrobial susceptibility is usually performed using phenotypic methods. In this study, we developed a universal 16S rRNA and rpoB quantitative PCR assay for susceptibility testing of bacteria commonly isolated in clinical microbiology laboratories. METHODS: Antibiotic susceptibilities for 24 bacterial strains of various species were tested by real-time quantitative PCR assay and by conventional methods. Quantification of DNA copies of either the 16S RNA genes or rpoB were recorded over time in the presence or absence of antibiotics to determine the bacterial growth kinetics and the optimal testing time. RESULTS: Molecular results for antibiotic susceptibility or resistance were in accordance with those obtained using a standard macrodilution broth assay. The method was reproducible, sensitive and rapid (2 h for Gram-negative bacilli and 4 h for Gram-positive cocci). Moreover, this assay was also able to determine the antibiotic susceptibilities of fastidious bacteria, such as mycobacteria, within 5 days. CONCLUSIONS: These results demonstrate that molecular detection of bacteria could be more rapid than phenotypic methods for antibiotic susceptibility testing.

Bacteria↗
PubMed2004

Reemerging threat of epidemic typhus in Algeria.

We report a case of epidemic typhus in a patient from the Batna region of Algeria, who presented with generalized febrile exanthema. The clinical diagnosis was confirmed by serological cross-adsorption followed by Western blotting. Our report emphasizes the threat of epidemic typhus in the highlands of Algeria.

Algeria↗
PubMed2003

[Fever after a tick bite: clinical manifestations and diagnosis of acute tick bite-associated infections in northeastern Switzerland].

BACKGROUND: Different tick-borne infections can cause an acute febrile illness. The study objectives were to investigate the clinical manifestations and diagnosis of infections among patients who presented with fever after a tick-bite, and to detect newly described pathogens, including Ehrlichia, Babesia and Rickettsia helvetica, in North-Eastern Switzerland. PATIENTS AND METHODS: : We studied 75 patients (41 male, 34 female, median age 38 years, among them 10 children) who had fever within 3 weeks after a tick-bite. Paired sera were tested for antibodies to Borrelia burgdorferi, tick-borne encephalitis virus, Anaplasma (Ehrlichia) phagocytophila, Babesia microti, B. divergens, and Rickettsia helvetica. In addition, microscopy and polymerase chain reaction was used to detect Ehrlichia. Clinical data were obtained at baseline and at 1 and 2 year follow-up. RESULTS: Tick-borne infections were confirmed or possible in 36 (48 %) patients: 7 (9 %) Erythema migrans, 6 (8 %) other specific manifestations of Lyme borreliosis, 6 (8 %) Lyme borreliosis presenting as non-specific febrile illness, 8 (11 %) tick-borne encephalitis, 7 (10 %) granulocytic ehrlichiosis, 1 B. microti infection in a traveler from the US and 6 (8 %) dual infections. In 8 (11 %) patients serological findings were suggesting possible acute or past R. helvetica infection. CONCLUSION: Among patients with fever after a tick-bite, Lyme borreliosis was most frequently found. There was no evidence for babesiosis among the resident population. Serologic data suggest that human granulocytic ehrlichiosis and R. helvetica infections may be endemic in Switzerland. Among 50 % of the patients no tick-borne infections could be diagnosed.

Acute Disease↗
PubMed2003

Detection of R. felis and R. typhi in fleas using monoclonal antibodies.

Rickettsia typhi and R. felis are flea-transmitted human pathogenic rickettsial species. To investigate the distributional dynamics of these rickettsiae we designed a micro-immunofluorescence assay (MIF) using species-specific monoclonal antibodies (MAbs) applied to flea cryosections. Our assay was performed in less than 3 h and its applicability was demonstrated by the detection of R. typhi in 50 artificially infected human body lice but in none of 50 uninfected lice. With MIF, we identified 31 positive among 32 fleas proven with PCR to be naturally infected with R. felis; and 7 positive among 32 fleas proven with PCR to be naturally infected with R. typhi. No cross-detection was observed with both MAbs. Fresh R. felis-infected fleas were significantly more MIF-positive than long conserved R. typhi-infected fleas (31/32 vs. 7/32, P < 0.01). This discrepancy may be linked to degradation of antigens by long-term freezing. For R. typhi-infected fleas, our assay was significantly more efficient when applied to fleas in early stages of infection (less than 15 days) by comparison with fleas frozen more than 20 days after infection (7/15 vs. 0/17, P = 0.01). This difference may be related to an antigenic modification caused by selection pressure in the vector and host process. The sensitivity of the described method did not exceed 47% (7/15) for R. typhi but, in contrast, was 97% for R. felis. Thus, our method appears to be useful for surveillance in R. felis infections, but requires further studies for the detection of R. typhi.

Animals↗
PubMed2003

Pericardial effusion in a homeless man due to Bartonella quintana.

Bartonella quintana may cause trench fever, endocarditis, bacillary angiomatosis, and chronic bacteremia, and a reemergence among homeless populations in cities has been noted. Pericarditis from Rickettsia conorii and Coxiella burnetii infection has been described, but there have been no reports of pericarditis due to Bartonella spp. We report a case of pericardial effusion due to Bartonella quintana in a homeless man, diagnosed on the basis of PCR detection of Bartonella quintana in a pericardial biopsy sample and a fourfold rise in antibody titers. The patient recovered within 2 weeks with antibiotics active against bartonellae.

Adult↗
PubMed2002

Introduction of the exotic tick Amblyomma hebraeum into Florida on a human host.

A resident of Florida returned from a short visit to southern Africa to find a male Amblyomma hebraeum tick attached to the skin behind her knee. Amblyomma hebraeum is a major vector of 2 pathogens that cause important diseases in southern Africa, heartwater of ruminants and African tick-bite fever of humans. The tick was tested by polymerase chain reaction assay for evidence of infection with Cowdria ruminantium and Rickettsia africae (the causative agents of heart-water and African tick-bite fever, respectively) and was found to be negative for both agents. This is the second record of the exotic tick, A. hebraeum, being introduced into the United States on a human host.

Africa↗
PubMed2001

Mechanisms of evolution in Rickettsia conorii and R. prowazekii.

Rickettsia conorii is an obligate intracellular bacterium that causes Mediterranean spotted fever in humans. We determined the 1,268,755-nucleotide complete genome sequence of R. conorii, containing 1374 open reading frames. This genome exhibits 804 of the 834 genes of the previously determined R. prowazekii genome plus 552 supplementary open reading frames and a 10-fold increase in the number of repetitive elements. Despite these differences, the two genomes exhibit a nearly perfect colinearity that allowed the clear identification of different stages of gene alterations with gene remnants and 37 genes split in 105 fragments, of which 59 are transcribed. A 38-kilobase sequence inversion was dated shortly after the divergence of the genus.

Adaptation, Physiological↗
PubMed2001

Risks factors and prevention of Q fever endocarditis.

Coxiella burnetii causes acute and chronic Q fever. To evaluate the risk factors of development of chronic endocarditis following Q fever and to assess the best preventive therapy, a retrospective study of patients diagnosed as having Q fever during 1985-2000 was conducted. Twelve patients with acute Q fever who developed endocarditis and 102 patients with Q fever endocarditis were included in the study. When compared to 200 control patients with acute Q fever, preexisting valvular disease (P<10(-7)), especially a prosthetic valve (P=.01), were encountered more often among patients with endocarditis. Among patients with valvular defects, we estimate the risk of developing endocarditis to be 39%. A combination of doxycycline plus hydroxychloroquine was better at preventing the development of endocarditis than doxycycline alone (P=.009). Our results should encourage physicians to detect valvular lesions in patients with acute Q fever and to search for acute Q fever in patients with a valvulopathy and unexplained fever. A proper treatment for such patients and a scheduled follow-up should reduce the risk of developing endocarditis.

Aged↗
PubMed2001

Rickettsia africae, a tick-borne pathogen in travelers to sub-Saharan Africa.

BACKGROUND: African tick-bite fever occurs after contact with ticks that carry Rickettsia africae and that parasitize cattle and game. Sporadic reports suggest that this infection has specific clinical and epidemiologic features. METHODS: We studied patients who were tested for a rickettsial disease after returning from a visit to Africa or Guadeloupe. To assess the value of the microimmunofluorescence assay, Western blotting, and cross-adsorption assays, we compared the results of these tests in 39 patients in whom African tick-bite fever had been confirmed by the polymerase-chain reaction assay, cell culture, or both; 50 patients with documented R. conorii infection; and 50 blood donors. These diagnostic criteria were then applied to 376 additional patients who had returned from southern Africa and 2 who had returned from Guadeloupe and whose serum was being tested for rickettsial disease. RESULTS: In the 39 patients with direct evidence of R. africae infection, the combination of microimmunofluorescence assay, Western blotting, and cross-adsorption assays showing antibodies specific for R. africae had a sensitivity of 0.56; however, each test had a positive predictive value and a specificity of 1.0. An additional 80 patients were found to have an R. africae infection on the basis of these serologic criteria. Infections with R. africae were acquired by visitors to 11 African countries and Guadeloupe. The illness was generally mild and was characterized by a rash in 46 percent of the patients; the rash was usually maculopapular or vesicular and rarely purpuric. Ninety-five percent of patients had an inoculation eschar or eschars, and 54 percent of these patients had multiple eschars, a finding that is unusual in patients with rickettsial infection. CONCLUSIONS: In this series, R. africae was the cause of nearly all cases of tick-bite rickettsiosis in patients who became ill after a trip to sub-Saharan Africa.

Adolescent↗
PubMed2001

Myocarditis, a rare but severe manifestation of Q fever: report of 8 cases and review of the literature.

Myocarditis has only rarely been described as a manifestation of acute Q fever. Among our series of 1276 patients in whom acute Q fever was diagnosed during 1985--1999, myocarditis was diagnosed in 8. Two patients (25.0%) developed cardiac symptoms during the course of interstitial pneumonia, 2 (25.0%) initially presented with unexplained fever, and 1 (12.5%) presented with febrile cutaneous rash. In 3 patients, cardiac symptoms were inaugural: 1 patient experienced heart failure, and 2 experienced precordial pain. Dilated cardiomyopathy was documented in 7 patients, and 2 (1 of whom had undergone heart transplantation) died despite therapy. In addition, 1 patient was scheduled for heart transplantation because of cardiac insufficiency. When the patients in this study were compared with 32 control patients with acute Q fever, no specific epidemiological or clinical features were associated with this disease except worse prognosis (P=.006). Moreover, among the 12 patients from our series who died as a result of acute Q fever, 2 patients, who were significantly younger than the other 9 patients (P=.03), had myocarditis. Our study highlights the severity of Coxiella burnetii myocarditis.

Adolescent↗
PubMed2001

Culture and immunological detection of Tropheryma whippelii from the duodenum of a patient with Whipple disease.

CONTEXT: Culture of Tropheryma whippelii has been established only once, in human fibroblast cell lines from a heart valve inoculum. Molecular-based diagnostic techniques, although highly sensitive, may be less specific. New diagnostic tools involving isolation of bacteria from contaminated intestinal biopsies and immunohistological detection need to be developed. OBJECTIVE: To describe a novel method for detection and culture of T whippelii strains. DESIGN, SETTING, AND SUBJECTS: Laboratory analysis of duodenal biopsy specimens from a patient with typical relapsing Whipple disease with intestinal involvement, performed Marseille, France, in March 2000. Biopsy specimens were decontaminated with antimicrobial agents and inoculated onto cell cultures. Mouse anti-T whippelii polyclonal antibodies were used to detect T whippelii in fixed specimens taken from the patient before and after relapse, compared with specimens from 10 controls. The genotype of the isolate was determined by amplification and sequencing of 2 DNA fragments (ITS and 23S rRNA). MAIN OUTCOME MEASURE: Isolation and genotyping of a new strain(s) of T whippelii from the case patient's biopsy specimens. RESULTS: A strain was grown from the case patient's intestinal specimen that has a genotype different from the first strain isolated. During 2 episodes of Whipple disease, T whippelii bacteria were detected by immunochemistry in the patient's duodenal biopsy specimens, but not in controls. CONCLUSIONS: A second strain of T whippelii has been isolated and a protocol for isolation from the intestine has been proven to be efficient. Immunodetection of T whippelii in intestinal biopsy specimens may provide a useful tool for the diagnosis and follow-up of patients with Whipple disease. Both techniques need further evaluation and confirmation.

Actinobacteria↗
PubMed2001

Phylogenetic position of Bartonella vinsonii subsp. arupensis based on 16S rDNA and gltA gene sequences.

The nucleotide sequences of the genes encoding 16S rRNA and citrate synthase (gltA) from a recently described member of the genus Bartonella, Bartonella vinsonii subsp. arupensis, isolated from mice and from the blood of a patient suffering from bacteraemia, were determined and compared with sequences of the 16S rDNA and gltA genes of other members of the genus Bartonella in order to determine its relative phylogenetic position. B. vinsonii subsp. arupensis appeared to be closely related to B. vinsonii subsp. vinsonii, another rodent-associated taxon, and to B. vinsonii subsp. berkhoffii, which was described recently in dogs.

Animals↗