A budding case of infectious endocarditis: Candida lusitania
Now open: Certificate Course in Management of Covid-19 by Govt. Of Gujarat and PlexusMDKnow more...Now open: Certificate Course in Management of Covid-19 by Govt. Of Gujarat and PlexusMDKnow more...
This is a case of recurrent Candida lusitaniae prosthetic valve endocarditis with budding yeast and pseudohyphae on the histopathology. It illustrates the importance of keeping vigilant in recognizing some of the emerging drug resistant Candida species in our practice

A 41-year-old Caucasian female with past medical history of intravenous drug abuse, chronic hepatitis C, and bioprosthetic mitral valve replacement due to infectious endocarditis was transferred to our facility for persistent fungemia and recurrent endocarditis. The original mitral valve replacement, presumptively due to a fungal organism, dated back approximately two years prior to presentation. Her initial presentation was also complicated by embolic events including thrombosis of the superficial femoral artery which required left above the knee amputation.

She had a subsequent admission for thrombosis of the celiac artery and Candida lusitaniae fungemia. She was discharged with plans for long term anticoagulation as well as 8 weeks course of intravenous micafungin. However, shortly after she was readmitted to an outside facility for left axillary artery thrombosis. During her stay C. lusitaniae was isolated in 5 sets of blood cultures despite continued treatment with micafungin. Two weeks into admission, a transesophageal echocardiogram demonstrated mitral valve vegetation. The patient was transferred to our facility for valve replacement.

Although Candida species are the most frequent fungal cause of infective endocarditis, C. lusitaniae is a rare etiology of the disease. Only a handful of cases have been documented in the literature with the first reported case of prosthetic valve endocarditis described in 1998. C. lusitaniae is notable for its resistance to amphotericin B, initially described in 1979. Infections by this species respond poorly to amphotericin in spite of in vitro testing frequently indicating low MICs. Whole genome sequencing has identified genetic similarities between C. lusitaniae and the recently emerging C. auris which can demonstrate resistance to multiple antifungal agents. In conclusion, in treatment of C. lusitaniae, it is crucial to recognize its resistance to amphotericin B and that first-line azole therapy frequently results in good outcomes in conjunction with surgical interventions.

Source: https://www.sciencedirect.com/science/article/pii/S221425091930318X