Breakthrough Fusarium solani fungaemia in a patient with acute myeloid leukaemia receiving posaconazole prophylaxis after three days concomitant omeprazole

Abstract

Introduction: Disseminated Fusarium infection carries a very high mortality therefore prevention remains the cornerstone in management of at risk patients. This approach incorporates the use of an appropriate broad spectrum antifungal agent with activity against both yeast and filamentous fungi. We report a case of breakthrough Fusarium solani infection in a 66-year-old neutropaenic female patient with acute myeloid leukaemia while on posaconazole prophylaxis. Case report: The patient was admitted with partial opacification of her maxillary sinuses and we believe that this served as the likely focus of infection. The fungus was isolated from blood 17 days post posaconazole prophylaxis and three days post omeprazole treatment though the Minimum Inhibitory Concentration (MIC) to posaconazole using the Clinical and Laboratory Standards Institute (CLSI) recommended method was very low. Three weeks treatment with liposomal amphotericin B proved to be successful, however, due to a rising creatinine the patient was subsequently changed to voriconazole with mycological and clinical cure. Conclusion: This case highlights the need for full histopathological and microbiological/ mycological investigations in patients with sinus opacification or mucosal thickening, alertness to Gram stain interpretation from blood cultures and above all, awareness that when proton pump inhibitors are used they might reduce triazole absorption.