The reproducibility of an enzyme-linked immunosorbent assay for detection of Chlamydia pneumoniae-specific antibodies.

With use of an enzyme-linked immunosorbent assay (ELISA), Chlamydia pneumoniae immunoglobulins were detected in a consecutive series of patients' sera (n = 122 for IgA and IgG; n = 138 for IgM). When the ELISA tests were repeated, the percentage disagreements were 12%, 16% and 10% for C. pneumoniae IgA, IgG and IgM, respectively. The reproducibility of the ELISA, expressed as kappa values, for IgA, IgG and IgM was 0.73, 0.60 and 0.53, respectively (p < 0.001). It was concluded that the ELISA had good reproducibility for detecting C. pneumoniae IgA, and moderately good reproducibility for detecting C. pneumoniae IgG and IgM.

Human enteric pathogens identified in a London teaching hospital and a rural public health laboratory: 1994.

Two microbiology laboratories, one serving an inner city hospital and one a rural public health laboratory, collected data on the outcome of examining faecal specimens in 1994. Overall, 6.7% of the investigations were positive, but the rates were lower for hospital inpatients, for recently described pathogens, and in the absence of relevant clinical details; rates were higher for patients with a history of foreign travel. No benefit was gained by examining more than two specimens from any patient. Clostridium difficile was the only investigation frequently positive among patients already in hospital, and virological tests were often positive in patients investigated by general practitioners.