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Jean-Marc Rolain

Publications and source records attributed to Jean-Marc Rolain.

At least 37 records · Page 2Linked to original sources

Is pyogenic granuloma associated with Bartonella infection?

Lobular capillary hemangioma and bacillary angiomatosis due to Bartonella infection share several clinical and histopathologic characteristics. We sought to determine whether lobular capillary hemangioma is caused by the same agent as bacillary angiomatosis. Forty-five pathology specimens with a histologic diagnosis of lobular capillary hemangioma obtained from patients with the same clinical diagnosis were tested by immunohistochemistry and polymerase chain reaction for the presence of DNA elements of Bartonella spp. None of the 45 lobular capillary hemangioma specimens tested positive for Bartonella spp. We conclude that lobular capillary hemangioma is not associated with Bartonella spp infection. Further research is required to determine the etiologic agent.

Angiomatosis, Bacillary↗

Correlation between ratio of serum doxycycline concentration to MIC and rapid decline of antibody levels during treatment of Q fever endocarditis.

Endocarditis is the major clinical manifestation of chronic Q fever. Although doxycycline along with hydroxychloroquine remains the mainstay of medical therapy for Q fever endocarditis, there are wide variations in the rapidity of the patient's decline of antibody levels during such therapy. We undertook a retrospective examination of whether there was any correlation between the ratio of serum concentration to MIC of doxycycline and response to treatment in patients with Q fever endocarditis. Included herein are 16 patients from whom Coxiella burnetii was isolated from cardiac valve materials. Serology and measurement of doxycycline and hydroxychloroquine serum levels were performed and recorded after 1 year of treatment. The MIC of doxycycline for C. burnetii isolates was determined using the shell vial assay in a real-time quantitative PCR assay. At the completion of a year-long therapy with doxycycline-hydroxychloroquine, all those that showed a low decline of antibody levels (n = 6) (i.e., <2-fold decrease in antibody titer to phase I C. burnetii antigen) had a ratio of serum doxycycline concentration to MIC between 0.5 and 1. In contrast, those having a ratio of > or =1 showed a rapid decline of phase I antibody levels (n = 9; P < 0.05). The only patient who died had a serum doxycycline-to-MIC ratio of <0.5, and the isolate of C. burnetii cultured from this patient was resistant to doxycycline (MIC = 8 microg/ml). The ratio of serum doxycycline concentration to MIC should be monitored during the course of therapy in patients with Q fever endocarditis.

Adult↗

Activity of telithromycin against thirteen new isolates of C. burnetii including three resistant to doxycycline.

In this study we have evaluated the in vitro activity of antibiotics against 13 new isolates of Coxiella burnetii using a real-time quantitative PCR assay. MICs against doxycycline ranged from 1 to 8 microg/mL, telithromycin from 0.5 to 2 microg/mL, and all strains had MICs > or = 8 microg/mL for erythromycin. We report that strains resistant to doxycycline exist either in humans or animals.

Animals↗

Bartonella quintana and Rickettsia felis in Gabon.

We detected Rickettsia felis DNA in Ctenocephalides felis and Bartonella quintana DNA in 3 Pulex irritans fleas taken from a pet Cercopithecus cephus monkey in Gabon, sub-Saharan Africa. This is the first report of B. quintana in the human flea.

Animals↗

High prevalence of Bartonella quintana endocarditis in Sfax, Tunisia.

Bartonella quintana is a fastidious microorganism associated with blood culture negative endocarditis. In this study, 40 sera with cross-reactivity between Chlamydia species from patients from Sfax, Tunisia, were serologically tested for Bartonella. Thirteen sera were positive for Bartonella with IgG titers >/=1:800. Western blot and cross-absorption confirmed the diagnosis of Bartonella quintana endocarditis in 12 cases and Bartonella henselae endocarditis in 1 case. These sera were also positive by LightCycler nested PCR amplification for the rnpb (7 of 13) and fur (11 of 13) genes. Eleven patients had a definite diagnosis of endocarditis, which represents 9.8% of all endocarditis. Because Bartonella endocarditis seems to be very common in Tunisia, we suggest that its serology be performed systematically whenever endocarditis is suspected.

Adult↗

Laboratory-confirmed Mediterranean spotted fever in a Japanese traveler to Kenya.

A Japanese traveler returning from Kenya became ill, presenting with fever and a prominent, generalized rash without an eschar. Results of the immunofluorescence antibody assay of the patient's sera performed in Japan were compatible with illness due to a spotted fever group (SFG) rickettsia, and a presumptive diagnosis of African SFG rickettsiosis, probably either Mediterranean spotted fever (MSF) or African tick-bite fever (ATBF), was rendered. To further define the disease diagnosis, sera were examined in France by Western immunoblotting combined with cross-adsorption, which confirmed the diagnosis of MSF but not of ATBF. Because of the need to further characterize the epidemiologic and clinical features of the two African SFG rickettsioses, clinicians are encouraged to contact a specialized laboratory when encountering such cases.

Antibodies, Bacterial↗

Measurement of the antibiotic susceptibility of Coxiella burnetii using real time PCR.

The objective of this study was to determine MICs of antibiotics for two reference strains of Coxiella burnetii using real time quantitative PCR. The method was very sensitive and specific and allowed the evaluation of the doubling time of Nine Mile and Q212 strains: 37 and 15 h, respectively. Dose response curves of antibiotics were used to determine MICs. Those of doxycycline, fluoroquinolone compounds and rifampicin were in the range 1-4 mg/l. Telithromycin was the most effective macrolide compound with MICs of 1-2 mg/l. The results confirmed previous reports on the accuracy of this new method for the determination of the antibiotic susceptibility of C. burnetii and could be used for the screening of new drugs.

Animals↗

Rickettsial infections--a threat to travellers?

PURPOSE OF REVIEW: Recent developments in cell-culture techniques and molecular methods have led to the description of several new rickettsial diseases. An update on these new infections should be of interest to health workers with patients who are international travellers. RECENT FINDINGS: Epidemic typhus was reported last year in the United States when an outbreak of murine typhus was recorded in Hawaii. Among spotted fever group rickettsioses, African tick bite fever is now probably the most common rickettsial infection in Africa with numerous cases also reported in international travellers. For the first time the Astrakhan fever rickettsia has been described outside Europe, in a French patient returning from Chad. Similarly, the first case of Rickettsia sibirica mongolotimonae infection in Africa was reported in 2004. Finally, a newly recognized agent of a spotted fever rickettsiosis, Rickettsia parkeri, has been reported in the United States during 2004. SUMMARY: Because results of serological testing are only presumptive, sophisticated methods are crucial for the diagnosis and description of new rickettsial diseases, especially in atypical cases. Modern diagnostic tools include cross-adsorption assays, Western blot testing, and cell-culture and molecular-biological methods.

Animals↗

Antibiotic susceptibility of Tropheryma whipplei in MRC5 cells.

Whipple's disease is considered a rare chronic disease with a broad spectrum of clinical manifestations. Several antibiotics have been used for the treatment of this disease, and the current reference treatment was determined empirically on the basis of only a few clinical observations. Patients should be treated for months, and many relapse after antibiotic withdrawal. We report here the first extensive study on the susceptibilities of three reference strains of Tropheryma whipplei to antibiotic in cell culture by using a real-time PCR assay as previously described. We found that doxycycline, macrolides, ketolides, aminoglygosides, penicillin, rifampin, teicoplanin, chloramphenicol, and trimethoprim-sulfamethoxazole were active, with MICs ranging from 0.25 to 2 microg/ml. Vancomycin was somewhat active at an MIC of 10 microg/ml. We found heterogeneity in the susceptibility to imipenem, with one strain being susceptible and the two other strains being resistant. Cephalosporins, colimycine, aztreonam, and fluoroquinolones were not active. We also demonstrated that a combination of doxycycline and hydroxychloroquine was bactericidal. This combination has been shown to be active in the treatment of patients suffering from chronic infections with Coxiella burnetii, a bacterium that is also found intracellularly in acidic vacuoles. We believe, then, that this combination therapy should be further evaluated in clinical trials for the treatment of Whipple's disease.

Adult↗

Prevalence of Bartonella clarridgeiae and Bartonella henselae in domestic cats from France and detection of the organisms in erythrocytes by immunofluorescence.

The prevalence of Bartonella infection in a pet cat population from France was found to be 8.1% (8 of 99 cats). The intraerythrocytic location of Bartonella clarridgeiae is shown for the first time, and we show that immunofluorescence detection of the organism in erythrocytes correlates with the number of bacteria in blood.

Animals↗

Can Whipple's disease be transmitted by gastroscopes?

OBJECTIVE: To determine whether disinfection protocols currently used for gastroscopes are effective against cultures of Tropheryma whipplei. DESIGN: The bactericidal activity of 2% glutaraldehyde and two peracetic acids on the Twist-Marseille strain of T. whipplei grown in cell monolayers was determined. PATIENTS: Two patients who were diagnosed as having Whipple's disease 3 years after they had had intestinal biopsies. RESULTS: The disinfectants reduced bacteria by approximately 2 log to 3 log10 after 5 to 60 minutes of contact. CONCLUSION: The bactericidal activity of a disinfectant is usually considered significant if it causes a 5 log10 or greater reduction in viable bacterial titers. Disinfecting gastroscopes with 2% glutaraldehyde or peracetic acids for 20 minutes may be insufficient to prevent transmission of T. whipplei on the instruments or stop false-positive results on polymerase chain reaction.

Actinomycetales↗

Detection of Astrakhan fever rickettsia from ticks in Kosovo.

Astrakhan fever is a summer spotted fever resembling Mediterranean spotted fever, endemic in Astrakhan, a region of Russia located by the Caspian sea. Its agent is a spotted fever group rickettsia, member of the Rickettsia conorii complex, transmitted to humans by Rhipicephalus sanguineus and Rhipicephalus pumilio ticks. In Summer 2001, French United Nations troops in Kosovo collected 2 ticks on asymptomatic soldiers (1 R. sanguineus and 1 Hyalomma marginatum) and 10 ticks on dogs (7 R. sanguineus, 2 Ixodes ricinus, and 1 H. marginatum) in the Morina region. By PCR amplification of both the gltA and ompA genes, we detected a rickettsia in 4 R. sanguineus, i.e., 3 of those collected on dogs and those taken from military personnel. As ticks were preserved in alcohol, culture was not possible. The sequences obtained from these PCR products identified, with a 100% homology, Astrakhan fever rickettsia. None of the other collected tick species was positive. The patient with the positive tick remained asymptomatic. Our study demonstrates, for the first time, the presence of Astrakhan fever rickettsia in ticks outside Russia. We suspect that the area of distribution of this rickettsia could be wider than initially suspected. Moreover, as R. sanguineus ticks bite humans, Astrakhan fever might be a cause of spotted fever in Kosovo.

Animals↗

Experimental infection of human erythrocytes from alcoholic patients with Bartonella quintana.

Bartonella spp. are found in the erythrocytes of their specific natural hosts and B. quintana bacteremia is associated epidemiologically with lice, alcoholism, and homelessness. The aim of our study was to compare the growth and the number of bacteria per erythrocyte in vitro in laboratory-infected red blood cells from alcoholic patients versus normal blood donor erythrocytes. Enumeration of bacteria was performed either with plate counting or with a real-time PCR quantitative assay. Number of bacteria per cell was determined using immunofluorescence assay and laser confocal microscopy. Although the number of bacteria after 4 days of incubation was similar in the two groups of erythrocytes, we found that the distribution of bacteria per erythrocyte in the two groups was different. Erythrocytes from alcoholics contain significantly more bacteria per cell than erythrocytes from blood donors. Our results suggest that there is a link between alcoholism and infections of B. quintana that may be due to the macrocytosis of erythrocytes.

Alcoholism↗

Culture and antibiotic susceptibility of Bartonella quintana in human erythrocytes.

Bartonella quintana, the agent of trench fever, has recently been implicated in various diseases, in particular, bacteremia and endocarditis in homeless people. The host cell of Bartonella spp. is believed to be the erythrocyte, and in the present study we demonstrate that B. quintana can be cultured in vitro in human erythrocytes. The bacteria were found to be intraerythrocytic by laser confocal microscopy with Bartonella species-specific monoclonal antibodies. Infections with B. quintana decreased the life span of erythrocytes in culture from 8.6 to 4.8 days. In the culture system we found that most of the antibiotics that we tested (doxycycline, fluoroquinolone compounds, and beta-lactams) were not bactericidal. Gentamicin was bactericidal at 4 micro g/ml, as was rifampin, but to a lesser extent. At this concentration, gentamicin has been shown to enter erythrocytes slowly and to reach a peak level of 0.26 micro g/ml after 24 h. At 0.26 micro g/ml, however, we found that gentamicin was not able to kill extracellular B. quintana, even after 96 h of incubation. We hypothesize that erythrocytes may be a reservoir for B. quintana and that the bactericidal activity of gentamicin that we observed occurs mainly when the bacteria emerge from the erythrocytes and are found extracellularly. It would appear that gentamicin should be administered for at least 5 days to cure patients infected with B. quintana.

Anti-Bacterial Agents↗

Molecular detection of Bartonella quintana, B. koehlerae, B. henselae, B. clarridgeiae, Rickettsia felis, and Wolbachia pipientis in cat fleas, France.

The prevalences of Bartonella, Rickettsia, and Wolbachia were investigated in 309 cat fleas from France by polymerase chain reaction (PCR) assay and sequencing with primers derived from the gltA gene for Rickettsia, the its and pap31 genes for Bartonella, and the 16S rRNA gene for Anaplasmataceae. Positive PCR results were confirmed by using the Lightcycler and specific primers for the rOmpB of Rickettsia and gltA of Bartonella. R. felis was detected in 25 fleas (8.1%), W. pipientis, an insect symbiont, in 55 (17.8%), and Bartonella in 81 (26.2%), including B. henselae (9/81; 11.1%), B. clarridgeiae (55/81; 67.9%), B. quintana (14/81; 17.3%), and B. koehlerae (3/81; 3.7%). This is the first report of the amplification of B. quintana from fleas and the first description of B. koehlerae in fleas from an area outside the United States. Cat fleas may be more important vectors of human diseases than previously reported.

Animals↗