Fluconazole Resistant Candida Oesophagitis in Immunocompetent Patients: Is Empirical Therapy Justifiable?

Candida Esophagitis Presenting as an Esophageal Pseudotumor

The typical appearance of Candida esophagitis is white plaque-like membranes within the esophagus. We describe a unique case of Candida esophagitis that presented as a bulky, malignant-appearing, positron emission tomography-computed tomography-avid mass on endoscopy. Esophageal candidiasis persisted despite a standard course of antifungal medications (fluconazole 400 mg daily for 14 days), and eradication was successful only after fluconazole 800 mg daily was administered. Malignancy was excluded based on 2 separate sessions of endoscopy with multiple biopsies and finally with endoscopic full-thickness resection assisted by preresection closure with an over-the-scope clip.

Clinical Characteristics and Manifestations of Fungal Esophagitis: A Single-Center Experience in South China

Fungal esophagitis is a common infectious disease, although the pathogenic clinical characteristics remain incompletely clear, especially in South China. The goal of this study was to investigate the pathogenic clinical characteristics of fungal esophagitis and the efficacy of different therapeutic strategies at a tertiary hospital in South China. A retrospective study was conducted from January 2007 to December 2017. Data from 113,390 patients who were treated in the endoscopic unit were retrieved and analyzed. To further understand the pathogen and risk factors for fungal esophagitis, we performed a case-control analysis of 101 patients and 202 controls. Of the 113,390 patients, 932 (0.82%) were positive. The annual detection rate ranged from 0.345% to 1.106%, showing an initially increasing and subsequently decreasing trend. The patients' median age was 49 years (range from 8 to 85), and most were men (615/932, 65.99%). Candida albicans was found in samples collected from 36 patients, without any drug-resistant strains. Age (P = 0.018), malignancy (OR = 4.031, 95% CI: 1.562~10.407), cigarette smoking (OR = 3.017, 95% CI: 1.645~5.533), and the use of antibiotics (OR = 2.178, 95% CI: 1.078~4.400) or immunosuppressants (OR = 6.525, 95% CI: 1.089~39.105) were independently associated with esophageal candidiasis. Fluconazole had a better curative effect than nystatin (OR = 4.047, 95% CI: 1.282~12.772) or simple observation (OR = 8.91, 95% CI: 2.61~30.49). In conclusion, fungal esophagitis primarily affects men and elderly individuals; it develops in the setting of malignancy, smoking, and certain previous medication use. Candida albicans is the most common pathogen and is sensitive to antifungal agents. Fluconazole has a good therapeutic effect.

Possible Risk Factors for Candida Esophagitis in Immunocompetent Individuals

Background

Candida esophagitis (CE) is a condition typically diagnosed in patients who are immunocompromised. Risk factors leading to the development of CE in immunocompetent patients have not been entirely elucidated. This study set out to identify risk factors associated with the development of CE in immunocompetent patients.

Methods

This study was a single-center retrospective chart review. Patients diagnosed with CE confirmed by endoscopic biopsy or brushings at our hospital between 2007 and 2017 were reviewed. The medical histories, endoscopy reports and pathology results were noted. Abdominal pain, heartburn, dysphagia and odynophagia were the common indications for endoscopy. A total of 241 patients were identified as having been diagnosed with CE by endoscopic brushing or biopsy. Of these patients, 161 were excluded due to the presence of immunocompromising and 80 patients were included who had no underlying immunocompromising conditions.

Results

Eighty patients with CE satisfied the inclusion criteria. The mean age of patients at the time of diagnosis was 39.8 years old (95% CI: 34.9 - 44.7). The incidences in men and women were similar in this study (49% women and 51% men). Of these patients, 56 (70%) (95% CI: 59-80%; P < 0.005) were taking proton pump inhibitors (PPIs). Fifteen patients (19%) had a previous upper endoscopy with evidence of reflux esophagitis, and they were all treated with PPIs and subsequently found to have CE on repeat upper endoscopy with a mean of 21.6 months of PPI treatment. There were 16 (20%) patients without any attributable risk factor and were completely healthy.

Conclusions

CE is an opportunistic infection typically seen in immunocompromised. We report incidence of CE in immunocompetent patients. In our cohort of immunocompetent patients, PPI use was the most common risk factor associated with the development of CE. This could be related to hypochlorhydria resulting from PPI use. However, the cause remains unclear in some patients.

Resistance Surveillance in Candida albicans: A Five-Year Antifungal Susceptibility Evaluation in a Brazilian University Hospital

Candida albicans caused 44% of the overall candidemia episodes from 2006 to 2010 in our university tertiary care hospital. As different antifungal agents are used in therapy and also immunocompromised patients receive fluconazole prophylaxis in our institution, this study aimed to perform an antifungal susceptibility surveillance with the C.albicans bloodstream isolates and to characterize the fluconazole resistance in 2 non-blood C.albicans isolates by sequencing ERG11 gene. The study included 147 C. albicans bloodstream samples and 2 fluconazole resistant isolates: one from oral cavity (LIF 12560 fluconazole MIC: 8μg/mL) and one from esophageal cavity (LIF-E10 fluconazole MIC: 64μg/mL) of two different patients previously treated with oral fluconazole. The in vitro antifungal susceptibility to amphotericin B (AMB), 5-flucytosine (5FC), fluconazole (FLC), itraconazole (ITC), voriconazole (VRC), caspofungin (CASP) was performed by broth microdilution methodology recommended by the Clinical and Laboratory Standards Institute documents (M27-A3 and M27-S4, CLSI). All blood isolates were classified as susceptible according to CLSI guidelines for all evaluated antifungal agents (MIC range: 0,125–1.00 μg/mL for AMB, ≤0.125–1.00 μg/mL for 5FC, ≤0.125–0.5 μg/mL for FLC, ≤0.015–0.125 μg/mL for ITC, ≤0.015–0.06 μg/mL for VRC and ≤0.015–0.125 μg/mL for CASP). In this study, we also amplified and sequenced the ERG11 gene of LIF 12560 and LIF-E10 C.albicans isolates. Six mutations encoding distinct amino acid substitutions were found (E116D, T128K, E266D, A298V, G448V and G464S) and these mutations were previously described as associated with fluconazole resistance. Despite the large consumption of antifungals in our institution, resistant blood isolates were not found over the trial period. Further studies should be conducted, but it may be that the very prolonged direct contact with the oral antifungal agent administered to the patient from which was isolated LIF E-10, may have contributed to the development of resistance.