Surveillance of the serum Candida antigen titer for initiation of antifungal therapy after post-remission chemotherapy in patients with acute leukemia.

The early diagnostic efficacy of serial Candida antigen detection by the assay kit CAND-TEC (a latex particle agglutination test) was evaluated in 12 episodes in 10 patients with acute leukemia after post-remission chemotherapy. To determine the timing to initiate antifungal chemotherapy, we performed the CAND-TEC assay serially in each patient. When the patients revealed febrile neutropenia after antileukemic chemotherapy and the Candida antigen titer was increased compared to that measured before the antileukemic chemotherapy (even if the increased titer was at a lower level, e.g., from negative to 1:1 positive or from 1:1 to 1:2), azole antifungal agents (fluconazole or miconazole) were administered intravenously. In 9 (81.8%) of the 11 evaluable cases, the antifungal chemotherapy was effective and the titers decreased to less than or equal to the previous titers in all cases. In 2 cases, the antifungal chemotherapy was not effective, and the titers did not decrease. These results suggest that serial Candida antigen detection provides a useful method in the early diagnosis of invasive candidiasis in febrile neutropenia and in determining the timing of the initiation of early antifungal chemotherapy. This method might also be useful in preventing the excess use of antifungal agents; thus preventing the proliferation of azole-resistant Candida infection.