Fatal Breakthrough Mucormycosis in an Acute Myelogenous Leukemia Patient while on Posaconazole Prophylaxis

Abstract

Posaconazole is a new oral triazole with broad-spectrum antifungal activity. Posaconazole has also shown a significant advantage of preventing invasive fungal infection compared to fluconazole or itraconazole in patients with prolonged neutropenia. Indeed, posaconazole has been commonly used for antifungal prophylaxis in patients undergoing remission induction chemotherapy for acute myelogenous leukemia or myelodysplastic syndrome. We experienced a case of fatal mucormycosis despite posaconazole prophylaxis. To our knowledge, this is the first reported case of fatal breakthrough mucormycosis in a patient receiving posaconazole prophylaxis during remission induction chemotherapy in Korea. This case demonstrated that breakthrough fungal infection can occurs in patients receiving posaconazole prophylaxis because of its limited activity against some mucorales.

Keywords: Leukemia, Myeloid, Acute; Mucormycosis; Posaconazole; Prophylaxis.

Figure 1. Chest X-ray (A) and CT scan of the chest (B) showed lobar pneumonia in the upper lobe and the superior segment of the right lower lobe on day 12 after chemotherapy. Follow-up chest X-ray (C) and CT scan of the chest (D) showed aggravation of pneumonia with pulmonary arterial invasion (red arrow) on day 26.

Figure 2. Microscopic analysis of the biopsy specimen showed broad width, non-septate, non-parallel sided, non-dichotomous branching and ribbon like hyphae consistent with mucormycosis (A: hematoxylin & eosin stain, ×400, B: periodic acid Schiff stain, ×400, C: Gomori methenamine silver stain, ×400).

Figure 3. Schematic presentation of the patient's clinical course.

TEC, teicoplanin; TZP, piperacillin/tazobactam; MEM, meropenem; PSC, posaconazole; AMB, amphotericin B deoxycholate; LAB, liposomal amphotericin B; IVIG, intravenous immunoglobulin; G-CSF, granulocyte-colony stimulating factor; ANC, absolute neutrophil count.