Candida parapsilosis: two cases of endocarditis in association with the Toronto stentless porcine valve

A case series of medically managed Candida parapsilosis complex prosthetic valve endocarditis

Background

In recent years, Candida parapsilosis is recognized as a species complex and is composed of Candida parapsilosis sensu stricto, Candida orthopsilosis and Candida metapsilosis. Candida parapsilosis complex prosthetic valve endocarditis (PVE) is rare and the survival rate is still low despite of optimal therapeutic strategies. In our report, it is novel to report cases as Candida parapsilosis complex PVE at species and identify Candida parapsilosis using MALDI-TOF MS.

Case presentation

A series of 4 cases of Candida parapsilosis complex PVE from our institution was reported. Three were infected by Candida parapsilosis sensu stricto and one was infected by Candida metapsilosis. The condition of two cases got better and the other died.

Conclusions

More attention should be paid to Candida parapsilosis complex PVE and early diagnosis and prompt antibiotic therapy may play a role in the treatment for Candida parapsilosis complex PVE. It is recommended to identify Candida parapsilosis complex at species level and MALDI-TOF MS as an easy, fast and efficient identification method is worth promoting in clinical microbiology

Candida endocarditis: systematic literature review from 1997 to 2014 and analysis of 29 cases from the Italian Study of Endocarditis

INTRODUCTION

Candida Endocarditis (CE) is a deadly disease. It is of paramount importance to assess risk factors for acquisition of both Candida native (NVE) and prosthetic (PVE) valve endocarditis and relate clinical features and treatment strategies with the outcome of the disease. Areas covered: We searched the literature using the Pubmed database. Cases of CE from the Italian Study on Endocarditis (SEI) were also included. Overall, 140 cases of CE were analyzed. Patients with a history of abdominal surgery and antibiotic exposure had higher probability of developing NVE than PVE. In the PVE group, time to onset of CE was significantly lower for biological prosthesis compared to mechanical prosthesis. In the whole population, greater age and longer time to diagnosis were associated with increased likelihood of death. Patients with effective anti-biofilm treatment, patients who underwent cardiac surgery and patients who were administered chronic suppressive antifungal treatment showed increased survival. For PVE, moderate active anti-biofilm and highly active anti-biofilm treatment were associated with lower mortality. Expert commentary: Both NVE and PVE could be considered biofilm-related diseases, pathogenetically characterized by Candida intestinal translocation and initial transient candidemia. Cardiac surgery, EAB treatment and chronic suppressive therapy might be crucial in increasing patient survival.

The role of fluconazole in the treatment of Candida endocarditis: a meta-analysis

The treatment of Candida infective endocarditis generally involves infected valve removal accompanied by antifungal therapy with amphotericin B or a lipid-based derivative, with or without flucytosine. While often used as chronic suppressive therapy in these patients, the precise role for fluconazole has not been established. We conducted a meta-analysis of 64 literature cases of Candida endocarditis whose management did not include valve replacement but who received fluconazole, alone or concurrently or in sequence with 1 or more other antifungal drugs.Forty-nine (77%) patients were cured (n = 44) or improved (n = 5), 4 relapsed (6%), and 11 failed (10 of whom died) (17%). Among 19 patients for whom fluconazole was administered as the sole antifungal therapy, 11 (58%) were cured or improved. In contrast, among 45 patients who received 1 or more other antifungal agents in addition to fluconazole, 38 (84%) were cured or improved (p = 0.02). Eighteen of 21 (86%) patients with native valve infection were cured or improved compared with 13 of 19 (68%) patients with prosthetic valve endocarditis (p = 0.13). The mean duration of successful fluconazole regimens was 134 days. Twenty of 21 (95%) patients who received fluconazole as chronic suppressive therapy for ≥6 months were cured. Prognosis was independent of Candida species or patient age. Among 23 historical controls managed with fluconazole-containing antifungal therapy plus valvular surgery, survival was 91%.In conclusion, fluconazole-containing, combination antifungal therapy, with or without concomitant valve replacement, and followed by prolonged, perhaps indefinite fluconazole suppression, is effective in patients with Candida endocarditis.

Differential in vitro activity of anidulafungin, caspofungin and micafungin against Candida parapsilosis isolates recovered from a burn unit

Recent studies suggest that differences in antifungal activity among echinocandins may exist. In this study, the activities of three echinocandins (anidulafungin, caspofungin, and micafungin) against Candida parapsilosis isolates from burn unit patients, healthcare workers and the hospital environment were determined. Additionally, the effect of these echinocandins on the cell morphology of caspofungin-susceptible and caspofungin-non-susceptible isolates was assessed using scanning electron microscopy (SEM). The C. parapsilosis isolates obtained from patients were susceptible to anidulafungin, but were less so to caspofungin and micafungin. Isolates obtained from healthcare workers or environmental sources were susceptible to all antifungals. SEM data demonstrated that although anidulafungin and caspofungin were equally active against a caspofungin-susceptible C. parapsilosis strain, they differed in their ability to damage a caspofungin-non-susceptible strain, for which lower concentrations of anidulafungin (1 mg/L) than of caspofungin (16 mg/L) were needed to induce cellular damage and distortion of the cellular morphology. To determine whether the difference in the antifungal susceptibility of C. parapsilosis isolates to anidulafungin as compared to the other two echinocandins could be due to different mutations in the FKS1 gene, the sequences of the 493-bp region of this gene associated with echinocandin resistance were compared. No differences in the corresponding amino acid sequences were observed, indicating that differences in activity between anidulafungin and the other echinocandins are not related to mutations in this region. The results of this study provide evidence that differences exist between the activities of anidulafungin and the other echinocandins.

Candida parapsilosis endocarditis: a comparative review of the literature

Fungal endocarditis (FE) is an uncommon disease, and while accounting for only 1.3-6% of all cases of infectious endocarditis, it carries a high mortality risk. Although Candida albicans represents the main etiology of FE, C. parapsilosis is the most common non-albicans species. We report the case of a 32-year-old man with a history of prior intravenous drug (IVD) use hospitalized with endocarditis due to C. parapsilosis and review all 71 additional cases documented in the literature. A retrospective analysis of the 72 C. parapsilosis cases compared to 52 recently reviewed cases of C. albicans endocarditis was conducted to identify organism-specific clinical peculiarities. The most common predisposing factor for C. parapsilosis endocarditis (41/72; 57.4%) involved prosthetic valves followed by IVD use (12/72; 20%). Peripheral embolic and/or hemorrhagic events occurred in 28/64 (43.8%) patients, mostly in cerebral and lower limb territories. Overall mortality was 41.7%. Combined surgical and clinical treatment was associated with a lower mortality. Few patients received the newer antifungal agents, and it would appear that more experience is required for their use in the treatment of C. parapsilosis endocarditis.

A meta-analysis of medical versus surgical therapy for Candida endocarditis

OBJECTIVES

The optimal management of Candida infective endocarditis (IE) is unknown.

METHODS

We reviewed all 879 cases of Candida IE reported from 1966-2002 in the peer-reviewed literature to better understand the role of medical and surgical therapies. This review included 163 patients from 105 reports that met our inclusion criteria: 31 cases treated with antifungal monotherapy, 25 cases treated with medical antifungal combination therapy, and 107 cases treated with adjunctive surgical plus medical antifungal therapy. We also used meta-analytic techniques to evaluate 22 observational case-series (72 patients) of the 105 reports with two or more patients with definite Candida IE.

RESULTS

We found that in patients who underwent adjunctive surgery there was a lower reported proportion of deaths [prevalence odds ratio (POR)=0.56; 95% confidence interval (CI)=0.16, 1.99)]. Higher mortality was noted in patients treated prior to 1980 (POR=2.03; 95% CI=0.55, 7.61), treated with antifungal monotherapy (POR=1.49; 95% CI=0.39, 5.81), infected with Candida parapsilosis (POR=1.51; 95% CI=0.41, 5.52), or with left-sided endocarditis (POR=2.36; 95% CI=0.55, 10.07).

CONCLUSIONS

Medical antifungal therapy of Candida IE is poorly characterized, and recent antifungal developments lend promise for those patients who cannot undergo surgery.