Limitation of the AccuProbe Coccidioides immitis culture identification test: false-negative results with formaldehyde-killed cultures.

The AccuProbe Coccidioides immitis culture identification test (CI test) yielded false-negative results with formaldehyde-killed C. immitis submitted to a reference laboratory. Further evaluation with pure or mixed cultures or stored, heat-killed cultures revealed the CI test to be highly sensitive and specific for C. immitis except when the cultures were pretreated with formaldehyde.