Common enterobacterial antigen in Yersinia enterocolitica

A review of serological tests to assist diagnosis of reactive arthritis: critical appraisal on methodologies

On a population-based level, the incidence of reactive arthritis (ReA) is 0.6–27/100,000. The definition of ReA varies and its pathogenesis is not yet clear. Attempts in basic immunology to suggest hypotheses for proliferation of forbidden B cell clones, molecular mimicry, and involvement of cross-reactive antibodies are helpful but not sufficient. Importantly, for the clinical diagnosis of the preceding infection, serology is widely used. Unfortunately, the accuracy of associations between serologic findings and clinical conclusions is plagued by poor standardization of methods. So far, few attempts have been done to examine the pitfalls of different approaches. Here, we review several serologic techniques, their performance and limitations. We will focus on serology for Yersinia, Campylobacter, Salmonella, Shigella, and Chlamydia trachomatis because these bacteria have a longer history of being associated with ReA. We also address controversies regarding the role of serology for some other bacteria linked to autoimmune disorders.

Indirect hemagglutination employing enterobacterial common antigen and Yersinia somatic antigen: a technique to differentiate brucellosis from infections involving cross-reacting Yersinia enterocolitica

The existence of enterobacterial common antigen in Yersinia enterocolitica and its absence in Brucella abortus were utilized in an attempt to provide a method to distinguish Brucella infections from infections with cross-reacting Yersinia. The indirect hemagglutination test was employed for this purpose. In experimental laboratory animals, the presence of anti-enterobacterial common antigen was found to be indicative of prior exposure to Y. enterocolitica rather than B. abortus. In cattle, however, low titers of anti-enterobacterial common antigen were present in all animals. It was observed that anti-enterobacterial common antigen titers either equaled or exceeded anti-Yersinia O titers in Yersinia-exposed animals, whereas in animals infected with B. abortus the anti-Yersinia O titer generally exceeded the anti-enterobacterial common antigen titer.

Faecal carriage of klebsiella by patients with ankylosing spondylitis and rheumatoid arthritis

In consecutive samples submitted to a clinical microbiology laboratory 22 out of 99 from outpatients and 23 out of 51 from inpatients yielded Klebsiella sp. A clinical reassessment of outpatients with ankylosing spondylitis (AS) and rheumatoid arthritis (RA) who had not been inpatients within the last year was made for disease activity and drug requirements. 124 patients with AS and 92 with RA were requested at assessment to submit a stool specimen for klebsiella examination, this being carried out without disclosure of the patient's clinical category. Two months later a questionnaire on symptom changes was collected and the results correlated with klebsiella carriage. Eighty-nine patients with AS and 82 patients with RA fulfilled all criteria for assessment. Of those assessed, 24 out of 89 AS patients and 26 out of 82 RA patients had klebsiella in the faeces. There was no correlation betweeh the initial clinical assessment category and klebsiella carriage. Seventy patients with AS and 57 paients with RA had no change in symptoms over the 2-month period. Nineteen AS patients and 31 RA patients noted symptom improvement or worsening. Of these, 3 AS and 10 RA patients had klebsiella in their faeces. There was no correlation between worsening of symptoms over a 2-month period and klebsiella carriage at initial assessment.