Adult mites' bodies of Dermatophagoides farinae were used as antigen in an indirect fluorescent antibody test (IFAT) to detect mite-specific IgG in sera of 48 patients with intestinal acariasis based on stool examination. Antibody titers with positive reaction ranged from 1:4 to 1:512 in 48 patients with intestinal acariasis. If antibody titers > or = 1:16 is regarded as being positive, the positive rate of patients detected with IFAT was 92%.