Shiga toxin-encoding genes (stx genes) in human faecal samples.

The aim of the two studies reported here was to investigate the distribution of stx genes in human faecal samples from volunteers and in faecal samples submitted to a regional microbiology hospital laboratory, and to isolate and characterize STEC from stx-positive samples. In total, faecal samples from 13.9% of 165 volunteers and 36.1% of 416 swabs from the regional microbiology hospital laboratory were positive for stx genes after screening by PCR. Isolation of STEC and of E. coli O157 from stx-positive faecal samples was performed by a filter-hybridization protocol and by automated immunomagnetic separation, respectively, and isolates were further characterized by serotyping, virulence typing by PCR and toxin production by the Vero cell assay. STEC were isolated from two samples only, an O146:H21 isolate from one of the volunteers and an O157:H7 isolate from a human case of diarrhoea. To conclude; the results show that it is not unusual to detect stx genes in faecal samples from humans in Norway, both from asymptomatic people and from people with gastrointestinal illness. This finding emphasizes the importance of correct diagnostic criteria for interpretation of the finding of an occasional stx-positive sample or an STEC isolate when searching for an aetiological agent of human cases of diarrhoea.

Antibodies to common infectious agents in coronary artery disease patients with and without rheumatic conditions.

OBJECTIVES: The mechanism linking inflammation to atherosclerosis is unknown. We have previously demonstrated a high occurrence of inflammation in the aortic adventitia of patients with coronary artery disease (CAD), which was more pronounced in patients with inflammatory rheumatic diseases (IRDs), and which might be involved in the pathogenesis of cardiovascular disease. In theory, infections might play a role in the pathogenesis of vascular inflammation or atherosclerosis, or both. This study compared seropositivity and the burden of several common infections in patients with CAD, both with and without IRD, and in healthy controls (HCs). Moreover, we looked for relationships between the examined antibodies and inflammatory infiltrates in the aortic adventitia. METHODS: We examined sera for Chlamydophila pneumoniae, Mycoplasma pneumoniae, Helicobacter pylori, CMV, Streptococcus pyogenes, parvovirus B19, HBV and HCV with commercially available serological tests in 67 patients with IRD, 52 patients without IRD and 30 HCs. RESULTS: We observed neither any statistically significant differences in the examined antibodies between the groups nor a difference in the burden of infection. Except for a protective effect of mycoplasma immunoglobulin A (IgA), we did not find any other associations between the examined antibodies and the occurrence of aortic adventitial mononuclear cell infiltrates. CONCLUSION: Our study does not support the notion that chronic infections or infectious burden contribute to accelerated occurrence of CAD in IRD. Mycoplasma IgA was related to a lower occurrence of aortic adventitial inflammation.

Septicaemia due to Actinobaculum schalii.

We report a case of septicaemia caused by Actinobaculum schalii, an Actinomyces-like bacterium, a gram-positive, non-sporulating rod. The search for the bacterium is relevant in cases with unexplained pyuri and septicaemia, because it may cause severe infection in predisposed humans. The bacterium is susceptible to a wide range of antibiotics.