Tetracycline in the Treatment of “Q” Fever

Powell, O. W.; Kennedy, K. P.; McIver, Monroe A.; Silverstone, H.

doi:10.1111/imj.1962.11.3.184

Cited by 29 publications

(21 citation statements)

References 5 publications

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“…Tetracycline, the reference treatment (11), is clinically effective when it is used alone (12), but it does not sterilize the infection. Combinations of antibiotics with tetracycline or its analogs are used.…”

Section: Discussionmentioning

confidence: 99%

Shell-vial assay: evaluation of a new technique for determining antibiotic susceptibility, tested in 13 isolates of Coxiella burnetii

Raoult

Torres

Drancourt

1991

Antimicrob Agents Chemother

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Coxiella burnetii is a strictly intracellular bacterium. Bacteriostatic effects have been described previously on a few isolates in embryonated eggs (A. J. Spicer, M. G. Peacock, and J. C. Williams, p. 375-383, in W. Burgdorfer and R. L. Anacker, ed., Rickettsiae and rickettsial diseases, 1981). We used the shell-vial technique (D. Raoult, G. Vestris, and M. Enea, J. Clin. Microbiol. 28:2482Microbiol. 28: -2484Microbiol. 28: , 1990) to determine the susceptibility of C. burnetii to amoxicillin, amikacin, erythromycin, co-trimoxazole, pefloxacin, ofloxacin, ciprofloxacin, chloramphenicol, tetraycline, doxycycline, minocycline, and rifampin antibiotics at a single dilution. Human embryonic lung fibroblast monolayers in shell vials were seeded with 13 different C. burnetii isolates, including 3 reference strains (Nine Mile, Q212, and Priscilla) and 10 new isolates, in order to obtain 30% infected cells 6 days later. After inoculation, antibiotics were added, shell vials were incubated for 7 days, and immunofluorescence was revealed and compared with that of the positive controls. Strain Nine Mile was more susceptible than strains Q212 and Priscilla were. The heterogeneity of susceptibility to fluoroquinolones, chloramphenicol, and erythromycin was noted among the strains; all were resistant to amoxicillin and amikacin, and all were susceptible to rifampin, co-trimoxazole, tetracycline, and tetracycline analogs.Q fever is a widespread disease caused by Coxiella burnetii. Two major forms of the disease are known: acute and chronic, which includes endocarditis. The clinical form of the disease is related both to host factors (14) and to strain specificity (5). It has been reported that strains isolated from patients with endocarditis are different from those isolated from patients with the acute form of disease (22,23). Acute Q fever is a self-limiting disease, and bacteriostatic antibiotic therapy is sufficient in these cases in order to shorten the duration of disease. Chronic Q fever is a severe, frequently lethal disease in which C. burnetii survives and the disease can relapse despite years of antibiotic treatment (3, 6-8, 10, 13, 16-18, 26-31). In these cases, a bacteriocidal activity is also required, but such activity has not been shown by the use of single-drug therapy in vitro (14). For antibiotic susceptibility testing, embryonated eggs (2, 9, 24, 32) and cell cultures (34) have been used. These techniques are timeconsuming and conveniently allow the testing of only a few antibiotics with a few isolates. We describe here a new antibiotic testing method which determines the bacteriostatic activity of antibiotic compounds by the newly described shell-vial technique (19). By this method, we compared the bacteriostatic effects of 12 antibiotic compounds on 3 reference isolates and 10 new human isolates of C. burnetii. MATERIALS AND METHODSC. burnetii isolates. The Nine Mile isolate, which is the reference isolate for acute infection (5), was obtained from 0. Baca (University of New Mexico, Albuquerque). The Q2...

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Section: Discussionmentioning

confidence: 99%

Shell-vial assay: evaluation of a new technique for determining antibiotic susceptibility, tested in 13 isolates of Coxiella burnetii

Raoult

Torres

Drancourt

1991

Antimicrob Agents Chemother

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“…Acute Q fever is a selflimniting infection which may present as prolonged fever, flulike illness, atypical pneumonia, hepatitis, or meningoencephalitis. Tetracycline and its analogs reduce the duration of fever (10,24), as do the fluoroquinolones pefloxacin and ofloxacin (3). Chloramphenicol is not clinically effective.…”

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confidence: 99%

In vitro susceptibilities of Coxiella burnetii, Rickettsia rickettsii, and Rickettsia conorii to the fluoroquinolone sparfloxacin

Raoult¹,

Brès²,

Drancourt³

et al. 1991

Antimicrob Agents Chemother

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In vitro susceptibilities of Rickettsia nckettsu, Rickettsia conoru, and CoxieUa burneti to the new fluoroquinolone sparfloxacin (AT4140; RP 64206) were determined. Plaque and dye uptake assays were used to measure the MICs against R. rickettsii and R. conoru. The susceptibifities of C. burnetii Nine Mile and Q 212 were determined in two acute-infection models and In two chroni-infection models. The MICs were 0.125 to 0.25 ,ug/ml for R. ,ickeffsu and 0.25 to 0.5 pg/ml for R. conoriu. Sparfloxacin (1 pg/ml) cured cells recently infected with C. burnetW Nine Mile and Q 212 within 4 to 9 days and cured multiplying, persistently infected cels within 10 days, As prevousl described with other fluoroquinolones (D. Raoult, M. Drancourt, and G. Vestris, Antimicrob. Agents Chemother. 34:1512Chemother. 34: -1514Chemother. 34: , 1990, sparfRoxacin failed to cure cells persistently infected with C. burnelii and blocked from dividing with cycloheximide. As determined by the dye uptake assay, no cellular toxicity was noted with spariloxacin at up to 128 gAg/mI. These results are consistent with those previously obtained with fluoroquinolones (D. Raoult, M. Yeaman, and 0. Baca, Rev. Infect. Dis. ll[Suppl. 5]:S986, 1989), although sparfloxacin may be slightly more active.Rickettsia rickettsii and Rickettsia conorii are the etiologic agents of Rocky Mountain spotted fever and Mediterranean spotted fever, respectively. These bacteria are antigenically (9) and genetically closely related and share the morphological characteristics and biochemical compositions of gramnegative bacteria. Both rickettsiae are strict intracellular pathogens, living free in the cytoplasm of infected host cells.

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“…Because of this, uncontrolled studies are of little value. A randomized study has been carried out with tetracycline alone, which reduced the duration of fever by 50% (23). However, treatment must be started within the first 3 days of illness to be effective.…”

Section: Medical Treatment Of Acute Q Fevermentioning

confidence: 99%