No abstract

The bacterial pathogen Chlamydia pneumoniae has been associated with atherosclerosis. Recent studies have reported chlamydial antigen to be present in atherosclerotic coronary arteries, but this relation has not yet been widely accepted. In order to verify an endovascular presence of potentially viable chlamydiae by detection of genomic DNA, the authors examined atherosclerotic carotid arteries by using a C. pneumoniae-specific nested polymerase chain reaction. Chlamydial DNA was detected in 9 of 61 (15%) arterial samples obtained from therapy of hemodynamically effective cervical vascular stenosis. Chlamydial presence was limited to advanced atherosclerotic lesions (P < or = 0.02): tissues from the same arteries with early subendothelial lesions did not harbor the pathogen. Thus, an etiologic role of C. pneumoniae is more plausible for progression than for initiation of atherosclerotic lesions. Histomorphologic discrimination of infected and noninfected samples was not possible and serology was unrewarding in detecting the infected patients. Chlamydial occurrence in atheromatous plaques is apparently a general phenomenon of atherosclerosis not limited to coronary arteries. Endovascular presence of genomic DNA of a bacterial pathogen susceptible to antimicrobial agents encourages thought on a new approach to prevent progression of atherosclerosis in a substantial proportion of patients. However, an etiologic contribution of C. pneumoniae in the multifactorial process of atherogenesis yet remains to be demonstrated.

Chlamydia pneumoniae has been associated to coronary artery disease by various methods including recovery of viable bacteria from plaques. The pathogenetical relevance of this is unclear but investigation of antichlamydial therapy in coronary arteriosclerosis is already in progress. The microimmunofluorescence test (MIF), the only species-specific serological assay available, might be considered useful in identifying patients with vascular chlamydial infection. However, this has never been systematically examined. We compared levels of C. pneumoniae antibodies in sera using MIF with direct detection of C. pneumoniae in coronary artery segments from 158 patients undergoing myocardial revascularization. A polymerase chain reaction (PCR) protocol, recently evaluated for use with vascular materials, detected C. pneumoniae infection in 34 patients. Correlation of serology and PCR was poor: in relation to PCR. MIF-IgG analysis had 21% sensitivity, 90% specificity, 37% positive predictive value, and 81% negative predictive value for detection of chlamydial presence. Thus, the MIF test currently appears not suitable to predict individual vascular C. pneumoniae infection.

Six medical students inhabiting a centuries-old, rat-infested house in Lübeck, in northern Germany, were suffering from itching papules and seropapules. Prior to these patients' visit to our institute, their conditions had been diagnosed as pediculosis, scabies, or pulicosis and treated unsuccessfully with the antiparasitic agent lindane (0.3%). The final diagnosis, tropical rat mite dermatitis, was based on the identification of the arthropod Ornithonyssus bacoti, which has an unsegmented body with eight legs. No treatment was recommended, and the dermatitis disappeared within 2 weeks. Measures taken to prevent reinfestation included extermination of the rats and treatment of the rooms of the house with the acaricide benzyl benzoate. Because the mite O. bacoti spends a relatively short time on a host and penetrates the skin for feeding only, the application of an antiparasitic agent is not necessary. If indicated, treatment should be symptomatic.