title: Serodiagnosis of pulmonary disease due to Mycobacterium avium complex with an enzyme immunoassay that uses a mixture of glycopeptidolipid antigens.
abstract: It is difficult to distinguish pulmonary disease due to Mycobacterium avium complex (MAC) from that due to other mycobacteria, such as Mycobacterium tuberculosis and Mycobacterium kansasii. We developed an enzyme immunoassay (EIA) for diagnosis of MAC pulmonary diseases that uses glycopeptidolipid (GPL) antigens specific for MAC, and we used it for diagnosis in immunocompetent patients. The mean optical densities (+/- standard deviation) of serum immunoglobulin G antibodies to GPLs in patients with MAC disease, MAC colonization, M. kansasii disease, and tuberculosis and in healthy subjects were 0.778+/-0.784, 0.042+/-0.035, 0.059+/-0.035, 0.071+/-0.035, and 0.030+/-0.027, respectively. A significant increase in the level of anti-GPL antibodies was detected in patients with MAC disease. The level of anti-GPL antibodies reflected disease activity, because the level was decreased in culture-negative patients who had conversion of culture results. When a cutoff level of seropositivity (0.119) was defined, the sensitivity of EIA for diagnosis of MAC disease was 92.3%, and the specificity was 96.7%. Measurement of serum anti-GPL antibodies is useful for both the diagnosis of and assessment of activity in MAC disease.
authors.affiliation: Department of Host Defense, Osaka City University Graduate School of Medicine, Abeno-ku, Osaka 545-8585, Japan.
authors.forename: Seigo
authors.initials: S
authors.lastname: Kitada
authors.forename: Ryoji
authors.initials: R
authors.lastname: Maekura
authors.forename: Naomi
authors.initials: N
authors.lastname: Toyoshima
authors.forename: Nagatoshi
authors.initials: N
authors.lastname: Fujiwara
authors.forename: Ikuya
authors.initials: I
authors.lastname: Yano
authors.forename: Takeshi
authors.initials: T
authors.lastname: Ogura
authors.forename: Masami
authors.initials: M
authors.lastname: Ito
authors.forename: Kazuo
authors.initials: K
authors.lastname: Kobayashi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000942:Antigens, Bacterial / Q000032:analysis*; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D007074:Immunoglobulin G / Q000276:immunology; D008171:Lung Diseases / Q000175:diagnosis* / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D015269:Mycobacterium avium Complex / Q000276:immunology* / Q000302:isolation & purification; D015270:Mycobacterium avium-intracellulare Infection / Q000175:diagnosis*; D012680:Sensitivity and Specificity; D012698:Serologic Tests
chemical_list: D000942:Antigens, Bacterial; D007074:Immunoglobulin G