Rehrig
University of New England College of Osteopathic Medicine, Biddeford Maine
Biography
Abstract
Introduction: Fungal endocarditis is a rare and severe form of infectious endocarditis. The treatment strategy requires aggressive intervention once diagnosed as mortality rates are as high as 50%. Current treatment standards recommend both medical and surgical intervention. Chronic oral immunosuppressive therapy is an option for outpatient treatment, though the efficacy of this treatment needs further support. Chronic antibiotic use poses a risk for resistance and highlights the need for close outpatient management.
Case Report: A 75-year-old African American male with a history of mitral valve replacement secondary to candida glabrata endocarditis was found to have bio-prosthetic valve thickening with mitral annular calcification on transthoracic echocardiogram (TTE) after a fall in his home. He was taking Fluconazole 400 mg as chronic immunosuppressive therapy since his first infection 11 months prior. Documented susceptibility reports showed the following minimal inhibitory concentrations (MIC): Voriconazole 0.25 ug/ml, Ketoconazole 0.25 ug/ml, Amphotericin B 0.5 ug/ml, and Caspofungin 0.06 ug/ml. We were unable to obtain this patient's susceptibility report for Fluconazole, but assume due to his therapy regimen, the patient initially qualified for its use. Transesophageal echocardiogram (TEE) supported the patient’s TTE, showing two masses attached to the mitral valve leaflets measuring 1.4x0.8 cm and 0.8x0.6 cm. Serum fungitell measured B-D glucan levels > 500 and a third round of peripheral blood cultures grew Candida glabrata. The patient was started on Micafungin 150 mg and transferred to a nearby facility where a successful mitral valve replacement was completed. Compared to prior results, the new susceptibility report showed increased resistance to all medications (Voriconazole 4.0 ug/ml, Ketoconazole 2.0 ug/ml, Amphotericin B 1.0 ug/ml, and Caspofungin 0.25 ug/ml). Fluconazole MIC was extremely high, reaching 256 ug/mL.
Discussion: Use of long-term antibiotics poses a risk for increasing rates of resistance in already difficult infections. Chronic suppression therapy has low-quality evidence but is still strongly recommended in the Infectious Disease clinical guidelines. Proper dosing and susceptibility testing are necessary for accurate treatment of infectious endocarditis, though guidelines for MIC interpretation of these organism-drug combinations have not been established. It is important to also consider the role of patient non-compliance when medications are taken for long lengths of time.