Evaluation of the use of 5-mycoloyl-beta-arabinofuranosyl-(1-->2)-5-mycoloyl- alpha-arabinofuranosyl-(1-->1')-glycerol in serodiagnosis of Mycobacterium avium-intracellulare complex infection.

5-Mycoloyl-beta-arabinofuranosyl-(1-->2)-5-mycoloyl-alpha-ar abinofuranosyl-(1-->1')-glycerol, an antigenic glycolipid from the Mycobacterium avium-intracellulare complex (MAC) was examined for its applicability to the serodiagnosis of MAC infection by ELISA. Serum IgM antibody titres against this glycolipid in healthy controls, pulmonary tuberculosis patients and sputum-MAC-culture-negative MAC patients were generally below the cut-off point (ELISA-negative), whereas most of the MAC-culture-positive MAC patient sera were ELISA-positive (93.5%) and their titres were often very high. Thus, high serum IgM titres against this glycolipid may be said to imply that the MAC disease is in an active phase.