No abstract

No abstract

A detection system for Legionella DNA in urine samples based on the polymerase chain reaction (PCR) was developed and tested on infected guinea pigs and patients suffering from pneumonia. Results were compared with standard methods for diagnosis of Legionnaires' disease. A primer system was selected which amplifies a 108 bp DNA fragment of the 5S rRNA gene. The sensitivity of the PCR system was one femtogram of extracted Legionella DNA. Three methods were tested for pretreatment of urine samples. Of these, the Geneclean II kit (Bio 101, USA) gave the best results for artificially contaminated urine samples as well as those from infected guinea pigs or patients. Thirty-seven urine samples from 15 guinea pigs intraperitoneally infected with either Legionella pneumophila serogroup 1, 3 and 6 or Legionella micdadei, 26 urine samples of 21 patients suffering from pneumonia, and 30 control samples of patients with urinary tract infection (UTI) were tested. Legionella DNA was detected in 29 of the guinea pig urine samples; whereas, urinary antigen detection using EIA was positive in only 20 of the samples. PCR was also positive in the samples of 11 patients with pneumonia, 9 of which were confirmed by other microbiological methods, such as culture, direct fluorescent antibody test, urinary antigen detection and antibody testing. However, of the 30 control samples from patients with UTI, three samples yielded positive results. The results demonstrate that Legionella DNA is excreted in the urine of infected individuals and that the PCR shows a higher degree of sensitivity than EIA to the detection of soluble Legionella antigen in urine.(ABSTRACT TRUNCATED AT 250 WORDS)

Eight Aspergillus antibody detection assays--three indirect haemagglutination assays (IHA-LD, IHA-Roche, IHA-Fumouze), three enzyme immunoassays (EIA-IgG, EIA-IgM, EIA-IgA, DDV) and two complement fixation tests (CF-metabolic and CF-somatic, Virion--and one latex agglutination test (LAT) for Aspergillus galactomannan antigen detection (Sanofi Pasteur) were evaluated in 14 patients with proven invasive aspergillosis (a total of 47 serum samples and one cerebrospinal fluid sample) and in 68 selected control individuals (one selected serum sample each). For the antibody tests, sensitivity ranged from 14% to 36% and specificity from 72% to 99%. The antigen detection test had a sensitivity of 36% and a specificity of 100%. Currently commercially available antibody detection assays for the serodiagnosis of invasive aspergillosis are inadequate. The antigen detection test appears to be highly specific, but lacks sufficient sensitivity.