Detection of Microbial Substitution in the Oral Cavity of Patients Undergoing Hematopoietic Stem Cell Transplantation with Vitek Mstm

Abstract

Objective: To estimate the incidence of IFD in multiple myeloma patients receiving autologous stem cell transplantation (ASCT) using novel agents (bortezomib, thalidomide) in addition to high-dose melphalan (VTD Mel). Patients and methods: Retrospective chart review of patients who received an ASCT with the novel regimen VDT Mel between 2012 and 2014 at UIHC. All toxicities related to transplant regimen were calculated for the first 100 days after ASCT. IFD were classified as proven, probable and possible according to the EORTC/MSG revised classification, 2008. Results: 100 consecutive patients who received ASCT with VTD Mel conditioning were analyzed; 47 patients received a single and 53 had tandem transplants (TT), respectively; all patients received standard fluconazole prophylaxis of 100 mg per day. Only infections ≥ grade 3 were listed; there were a total 5 episodes of IFD with 4 proven and 1 probable fungal infections. Only 1 of the 4 proven infections was a mold infection (Alternaria sp).The 3 other proven infections were candida sepsis; 2 occurred in the same patient with the TT. Infections occurred between 6 and 10 days post-transplant. All patients were treated with appropriate antifungal therapy and one patient with proven mold infection required debridement of the sinus. There were no mortalities related to fungal infections in the first 100 days or long term with a median follow-up of 16.2 months. All patients except one had extensive prior therapy with 3 lines. We observed false positive beta D glucan and galactomannan tests in 7 other patients. Conclusion: This is the first study to report on the rates of invasive fungal disease in MM patients treated with novel agents as part of conditioning regimen. The rate of IFD, 4% (4/100 patients) in our patients, is within the range of published literature which reported IFD rates of~2.5% and~15% in patients receiving ASCT and more than 3 lines of therapy, respectively. We did not observe any mortality associated with IFD. History of prior heavy chemotherapy could be an additional risk factor. Risk of infection is high in the early posttransplant phase and prompt, aggressive treatment may lead to good outcomes. Fluconazole remains the standard prophylactic agent, since the duration of neutropenia is limited for most patients.