Scandinavian journal of infectious diseases. Supplementum最新文献

Chlamydia pneumoniae infection has been implicated in several chronic lung diseases by serology and direct antigen detection. Acute lower respiratory tract infection caused by C. pneumoniae seems often to precede attacks of asthma in both children and adults. Chlamydia pneumoniae is also involved in some exacerbations of chronic bronchitis and chronic obstructive lung disease but, more importantly, seems to be strongly associated with the latter irrespective of exacerbation status. Moreover, persistently elevated C. pneumoniae antibody titres have been observed in sarcoidosis and lung cancer.

The association of Chlamydia pneumoniae to several chronic diseases such as atherosclerosis has been suggested serologically and by direct demonstration of organisms in disease lesions. Cell mediated immunity is crucial in host defense against intracellular pathogens such as C. pneumoniae. C. pneumoniae is a relatively recently recognized pathogen and the cellular mechanisms in C. pneumoniae immunity have so far remained unstudied. The present review includes the data available on C. pneumoniae proteins and their role as T cell activating antigens and Th1/Th2 balance in C. pneumoniae immunity.

The objective of this investigation was to determine whether Chlamydia pneumoniae was involved in an outbreak of respiratory disease among military recruits, 92 patients (average age 20.1 years) were included in the study if they had a sore throat or cough for more than 1 week. In addition to sore throat and cough, fatigue, headache, dyspnoea and vertigo were the most frequent symptoms. The patients received standard treatment with 100 mg of doxycycline b.i.d. for 14 days. In 38.8% of cases symptoms were alleviated after 1-2 weeks of treatment, and in 22.4% of cases after 2-3 weeks of treatment. Pretreatment throat washings and sera were sampled for Chlamydia. Sera were drawn for Chlamydia, Mycoplasma and adenovirus serology. Cell culture (Hep-2) and 3 different serological methods-microimmunofluorescence (MIF), enzyme immunoassay with a recombinant glycoconjugate antigen (r-EIA) and immunoperoxidase assay (IPA)-were used. Cell culture was found to have too low a sensitivity to be of diagnostic value. Acute infection was demonstrated in 13% by MIF IgM and in an additional 21% by MIF IgG (titre rises). Enzyme immunoassay IgM was found in 17% and IPA IgM in 19% of individuals without MIF IgM antibodies. Microimmunofluorescence was found to be the most useful test for serodiagnosis. The combination of serological methods showed that 40 out of 52 (76.9%) had an acute infection with possible chlamydial aetiology. In conclusion, methodological improvements are necessary for the aetiological diagnosis of chlamydial respiratory infections.

The microimmunofluorescence antibody technique was used to determine the seroprevalence of antibodies to Chlamydia pneumoniae and Chlamydia psittaci from hospitalized patients in Hong Kong. Antibodies to C. pneumoniae were found in 54.8% of 157 patients hospitalized with respiratory disease, in 71.1% of 83 patients with cardiac disease and in 31.2% of 93 patients without either respiratory or cardiac disease. Antibodies to C. psittaci were found in 0.9% of the combined study groups. There was serological evidence of C. pneumoniae being the responsible agent in 24.8% of the severe respiratory cases. A significant correlation between antibody prevalence and coronary heart disease was identified during the study.

It is a common clinical experience that the onset of the so called non infectious vasculitides is often preceded by upper respiratory tract symptoms. A specific agent is only occasionally recovered. We report five cases in Sweden with manifestations of vasculitis from different organs. In three of the five patients the onset was preceded by upper respiratory tract symptoms. All patients had serologic findings indicating Chlamydia pneumoniae infection and all required corticosteroid treatment for symptomatic recovery. One was diagnosed as an aseptic meningitis. Another was diagnosed as a cerebral arteritis, probably a variant of a giant cell arteritis. A third patient had symptoms similar to a polymyalgia rheumatica engaging the thighs. Two patients had an acute myocardial infarction. One of them had Cogan's syndrome. The other also had pulmonary and hepatic engagement and an elevated level of anti basement membrane IgM antibodies, though not to the Goodpasture antigen. He had no renal involvement. The diagnosis of Chlamydia pneumoniae infection was based on the detection of species-specific IgA, IgG and IgM antibodies to Chlamydia pneumoniae using microimmunofluorescence technique, MIF. Four of the 5 cases exhibited a fourfold increase in antibody titers, and the fifth case was found to have high levels of IgG and IgA antibodies, suggesting recent infection. Investigations for other infectious agents were negative in all patients. The serologic findings in those patients are consistent with a pattern of reinfection with Chlamydia pneumoniae. We therefore suggest that reinfection with Chlamydia pneumoniae may induce isolated and systemic vasculitis in virtually any organ of the body.

The Swedish Reference Group for Antibiotics (SRGA) is an expert committee within the Swedish Medical Society and has been working with different aspects of susceptibility testing of bacteria to antibiotics since 1978. The emphasis has been on standardization of methodology, evaluation of the in vitro activity of new and old antibiotics, and the detection and significance of resistance mechanisms in bacteria. In the following a review is presented of the work conducted by the SRGA.

A subcommittee of the Swedish Reference Group for Antibiotics, SRGA-M, has worked with standardization of methodology for susceptibility testing. In vitro data obtained with the disk diffusion procedure were collected from 5 clinical laboratories, compiled and presented as histograms of inhibition zones, and compared with data [minimum inhibitory concentrations (MICs) and inhibition zones] obtained from the reference laboratory at the Swedish Institute for Infectious Disease Control on a collection of clinically relevant bacterial species. Results from the reference collection of strains were presented as MIC histograms, and their corresponding inhibition zones were inserted in the compiled zone histograms as identifiable bars. These distributions formed the basis for decisions of breakpoints. Special tests were recommended for the detection of certain resistance mechanisms. A beta-lactamase test should be used for Haemophilus influenzae, Moraxella catarrhalis, Neisseria gonorrhoeae and enterococci. Screening for beta-lactam resistance caused by altered penicillin binding proteins should be done by using oxacillin 1 microgram for Streptococcus pneumoniae and Staphylococcus aureus (MRSA), and by phenoxymethylpenicillin 10 micrograms for H, influenzae. The standardized disk diffusion procedure was helpful in detecting enterobacteria carrying beta-lactamases with extended spectra. Registration of inhibition zones will provide a powerful tool for the epidemiological surveillance of antibiotic resistance.

There is accumulating evidence that persistent Chlamydia pneumoniae infections occur in vivo. Animal studies are necessary in order to evaluate the effects of different treatment regimens for eradication of such infections. A mouse model was found to be efficacious for the study of the effects of cortisone and antimicrobial agents on C. pneumoniae infection.