The three peripherals wells with precipitin bands contain sera from patients with A. fumigatus fungus ball (FB). More bands present in the upper right cases is characteristic of FB. The well in the bottom left position is negative.
Double diffusion test for aspergillosis. Central well contains Aspergillus fumigatus antigen and wells in the top and bottom contain control antiserum.
Images supplied by LC Severo, with the help of AC Pasqualotto, at Santa Casa Complexo Hospitalar, Porto Alegre, Brazil.