rifampin and Psittacosis

Antimicrobial treatment of chlamydial infections is known to be of limited efficacy. In this study, effects of doxycycline (D), usually the drug of choice, were compared with the combined therapy of doxycycline and rifampicin (R) in a bovine model of respiratory Chlamydia psittaci infection. After intrabronchial inoculation of the pathogen, 30 animals were assigned to five groups (n = 6 per group): untreated controls, monotherapy with D (5 mg kg(-1)day(-1) or 10 mg kg(-1)day(-1)), and combination therapy of D and R (600 mg day(-1)). Treatment continued until day 14 post inoculation (d.p.i.). Clinical signs, inflammatory markers, and pathological findings confirmed successful infection in all animals. Reisolation of the pathogen was possible in 4/6 untreated animals and in 4/12 animals treated with D alone until 4 d.p.i., but in none of the calves of the two D + R groups. Pathogen detection was possible in all animals without significant differences among groups. Severity of disease and time course of its resolution, assessed by clinical and pathological findings as well as inflammatory parameters, were not significantly different between untreated controls and calves receiving D alone or in combination with R. Regardless of the treatment regimen, all groups recovered clinically and cleared the infection within 2 weeks.

Topics: Animals; Anti-Bacterial Agents; Bronchoalveolar Lavage Fluid; Cattle; Chlamydophila psittaci; Disease Models, Animal; Doxycycline; Drug Therapy, Combination; Lung; Male; Prospective Studies; Psittacosis; Rifampin; Severity of Illness Index; Time Factors; Treatment Outcome

Chlamydia psittaci is a zoonotic bacterium with a wide host range that can cause respiratory disease in humans and cattle. In the present study, effects of treatment with macrolides and quinolones applied alone or in combination with rifampicin were tested in a previously established bovine model of respiratory C. psittaci infection. Fifty animals were inoculated intrabronchially at the age of 6-8 weeks. Seven served as untreated controls, the others were assigned to seven treatment groups: (i) rifampicin, (ii) enrofloxacin, (iii) enrofloxacin + rifampicin, (iv) azithromycin, (v) azithromycin + rifampicin, (vi) erythromycin, and (vii) erythromycin + rifampicin. Treatment started 30 hours after inoculation and continued until 14 days after inoculation (dpi), when all animals were necropsied. The infection was successful in all animals and sufficient antibiotic levels were detected in blood plasma and tissue of the treated animals. Reisolation of the pathogen was achieved more often from untreated animals than from other groups. Nevertheless, pathogen detection by PCR was possible to the same extent in all animals and there were no significant differences between treated and untreated animals in terms of local (i.e., cell count and differentiation of BALF-cells) and systemic inflammation (i.e. white blood cells and concentration of acute phase protein LBP), clinical signs, and pathological findings at necropsy. Regardless of the reduced reisolation rate in treated animals, the treatment of experimentally induced respiratory C. psittaci infection with enrofloxacin, azithromycin or erythromycin alone or in combination with rifampicin was without obvious benefit for the host, since no significant differences in clinical and pathological findings or inflammatory parameters were detected and all animals recovered clinically within two weeks.

Topics: Animals; Anti-Bacterial Agents; Azithromycin; Cattle; Chlamydophila psittaci; Disease Models, Animal; Enrofloxacin; Erythromycin; Fluoroquinolones; Inflammation; Macrolides; Male; Psittacosis; Rifampin

While the term "atypical pneumonia" has been in use for many years, it cannot in fact be defined. However, there is a persuasive reason to retain the clinical use of the term, and that is to provide a guide for the clinician in the choice of empirical antibiotic therapy for patients with acute pneumonia. Atypical pneumonia, then, is a descriptive term for a common clinical syndrome. Provided certain clinicoepidemiological groups are excluded, the most common infectious causes of this syndrome are Mycoplasma pneumoniae, Chlamydia psittaci, Coxiella burneti, and Legionella species, but it should be stressed that the syndrome may occasionally be produced by other infectious and non-infectious diseases. Conversely, the atypical pneumonia syndrome occupies only one part of the clinical spectrum of disease that is caused by these organisms. This becomes important when one is selecting antibiotic therapy for patients with other respiratory syndromes, especially those with life-threatening disease. The antimicrobial therapy of the three common causes of atypical pneumonia is discussed in detail.

Topics: Anti-Bacterial Agents; Erythromycin; Humans; Legionnaires' Disease; Pneumonia; Pneumonia, Mycoplasma; Psittacosis; Rifampin; Tetracycline

Topics: Adult; Endocarditis, Bacterial; Humans; Male; Psittacosis; Rifampin

A 45-year-old male who had looked over pet-birds at a bird shop 11 days before, developed a high fever with chills. Without any response to cephalexin, he was admitted to the hospital, with the chief complaints of high fever and sever headache on the 8th day of illness. The chest X-ray films taken then revealed a fun-shaped ground glass-like shadow extending over S10 of the right lung. After the oral administration of 450 mg rifampicin on the 9th day of illness, he became a febrile within one day and was cured with the same daily doses for the following 10 days. Chlamydia was isolated from the peritoneal exudate of the mice inoculated with throat mucus of the patient taken prior to the administration of rifampicin. Complement fixation reaction for psittacosis was positive in a titer of 1 : 16 on the 11th day of illness and rose to 1 : 64 in a week.

Topics: Animals; Chlamydophila psittaci; Humans; Male; Mice; Middle Aged; Mouth Mucosa; Psittacosis; Rifampin