Antifungal drug resistance pattern of Candida. spp isolated from vaginitis in Ilam-Iran during 2013-2014

The occurrence of fungi from burn wound patients and antifungal susceptibility patterns: a cross-sectional study in Lusaka, Zambia

Background

Fungal opportunistic infections in burn wound patients are among the leading cause of morbidity and mortality. Attention remains focused on preventing bacterial infection at the expense of increasing fungal infection in burn wound patients.

Objective

To determine the occurrence of common fungi in admitted burn wound patients and their environment: and their antifungal susceptibility patterns at the University Teaching Hospitals, Lusaka, Zambia.

Methods

This laboratory-based cross-sectional study enrolled a total 101 participants whose pus swab specimens were collected from their burn wounds as well as 50 environmental swabs collected from strategic points. Wet mount, gram stain, culture on Sabouraud dextrose agar, Corn meal agar and Germ tube were used to identify possible fungal isolates. Agar based disc susceptibility test was carried out using fluconazole. Data was analysed using Excel and STAT version 14.

Results

Median age was 3 years and median burn % of TBSA was 18 in participants' who had burn wound fungal infection and consisted of 3 males and 6 females. Organisms isolated included Candida albicans from 8(7.9%) participants and 2(4%) from 50 environmental swabs. 1(1%) Candida spp was isolated from pus swabs. Out of the total 11 Candida isolates, 4 (36.4%) were susceptible to fluconazole and 7 (63.6%) were resistant.

Conclusion

The isolation of Candida albicans and Candida spp from burn wound patients and the hospital ward environment suggests presence of fungi in burn wound patients and hospital ward environments. Candida isolated showed varying susceptibility patterns to fluconazole.

Expression pattern of drug-resistance genes ERG11 and TAC1 in Candida albicans Clinical isolates

BACKGROUND

Candida albicans (C. albicans) is an opportunistic fungus and the most common cause of vulvovaginal candidiasis (VVC). In recent years, the use of antifungal drugs has led to the incidence of drug-resistant C. albicans strains. The purpose of this study is twofold: to determine the pattern of drug susceptibility and the relationship between demographic factors and the incidence of drug resistance among C. albicans isolates and to investigate the expression pattern of drug-resistance genes ERG11 and TAC1 in C. albicans isolates.

METHODS AND RESULTS

This descriptive cross-sectional study was conducted on 50 C. albicans isolates from women with VVC. Antifungal susceptibility of the isolates was tested by M27-A3/S4 broth micro dilution method following the Clinical and Laboratory Standards Institute (CLSI) guidelines. High susceptibility rates were recorded for itraconazole and voriconazole (68%), followed by ketoconazole (46%). Fluconazole had the lowest susceptibility to C. albicans with susceptibility of 36%. The change in ERG11 and TAC1 genes expression was determined by qPCR. The mean ∆Ct values of ERG11 and TAC1genes were significantly different between fluconazole-resistant and susceptible groups (p < 0.001). Interestingly, we found that 77% of fluconazole-susceptible isolates had significantly upregulated ERG11 gene (2.9-99.0 fold). In addition, the expression of TAC1 was upregulated in 44% of fluconazole-susceptible isolates (3.86-89.8 fold).

CONCLUSION

Our finding revealed that incidence of drug resistance in C. albicans is not simply controlled by genes but is a multi-factorial phenomenon, where several factors and mechanisms are involved in the process of drug resistance.

Azole Antifungal Resistance in Candida albicans and Candida glabrata Isolated from Vulvovaginal Candidiasis Patients

Background: Vulvovaginal candidiasis (VVC) is the most frequent fungal disorder in healthy and normal women. Objectives: The aim of this study was to evaluate the in vitro antifungal susceptibility of clinical isolates Candida albicans and Candida glabrata, the two most common candida species in Iranian patients with VVC. Methods: One hundred and eight clinical isolates of candida, including; C. albicans (n = 77) and C. glabrata: (n = 31) were isolated from the 108 patients with VVC. The in vitro activity of caspofungin (CAS), amphotericin B (AMB), voriconazole (VRC), itraconazole (ITC), fluconazole (FLC), and nystatin (NYS) were determined according to the CLSI M27-A3 and CLSI M27-S4. Results: Our results were shown 8 (25.8 %) and 6 (7.8 %) C. glabrata and C. albicans isolates resistance to FLU, respectively. Furthermore, resistance to VRC and ITC were observed in 8.4%, and 3.7% of all isolates, and six isolates (5.6%) had intermediate MIC to CAS. Conclusions: We reported 8 (25.8 %) and 6 (7.8 %) C. glabrata and C. albicans isolates resistance to FLU, respectively. Furthermore, resistance to VRC and ITC were observed in 8.4% and 3.7% of all isolates, respectively.

Molecular Characterization and Antifungal Susceptibility of Candida Species Isolated From Vulvovaginitis in Jahrom City, South of Iran

Background: Vulvovaginal candidiasis (VVC) is a significant health issue due to Candida spp. Although Candida albicans is considered a major causative agent of vaginal candidiasis, non-albicans species have increased during previous decades. Objectives: This research aimed at molecular identification and assessing antifungal susceptibility of VVC isolated Candida spp. Methods: A professional physician examined two hundred and ninety-five suspected females with vaginitis. The specimens were collected by sterile cotton swabs. Swabs were inoculated on Sabouraud dextrose agar plates and then incubated for 48 - 72 hours at 35°C. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to detect all Candida species. Broth microdilution, according to the M27-A3 and M27-S4 CLSI documents, were employed for determining the antifungal susceptibility tests of caspofungin (CAS), voriconazole (VRC), itraconazole (ITC), fluconazole (FLU), clotrimazole (CLO), ketoconazole (KTO), amphotericin B (AMB), and nystatin (NYS). Results: A total of 295 females suspected of vulvovaginal candidiasis were examined. The culture results were positive in 50.5% (149 of 295) of specimens. According to molecular identification techniques, C. albicans 133/149 (89.2%), C. glabrata 8/149 (5.4%), and C. kefyr 2/149 (1.4%) were the main species. A mixed infection of C. albicans and C. glabrata 6/149 (4 %) was detected. The geometric mean values to all Candida strains were in increasing order as the following: CAS, 0.075 µg/mL; VRC, 0.091 µg/mL; ITC, 0.15 µg/mL; AMB, 0.22 µg/mL; CLO, 0.23 µg/mL; KTO, 0.28 µg/mL; NYS, 0.88 µg/mL; FLU, 1.48 µg/mL. Further, the MIC ranges of all Candida isolates to the tested antifungal agents were in increasing order as follows: CAS: 0.031 - 0.25 µg/mL, KTO and ITC: 0.031 - 2 µg/mL, VRC: 0.031 - 4 µg/mL, CLO and AMB: 0.031 - 8 µg/mL, NYS: 0.06 - 4 µg/mL, and FLU: 0.12 - 128 µg/mL. Conclusions: We reported 1 (7.2 %) C. glabrata isolate resistance to FLU and 2 (14.3%) C. glabrata isolates susceptible-dose-dependent (SDD) to CAS. We also reported 6 (4.5%), 5 (3.8%), and 2 (1.5%) C. albicans resistance to ITC, FLU, and AMB, respectively, but 100% C. albicans susceptible to CAS and VRC.

High prevalence of itraconazole resistance among Candida parapsilosis isolated from Iran

Background and Purpose:

Candida parapsilosis isolates usually have a low minimum inhibitory concentration (MIC) against azoles. Although Candida parapsilosis isolates usually have low MICs against azoles, recent studies candida invasive infections due to azole resistant-C. parapsilosis isolates . Regarding this, the main aim of this study was to determine the susceptibility pattern of Iranian clinical C. parapsilosis against available azole antifungal drugs.

Materials and Methods:

This study was conducted on 105 previously-identified isolates of C. parapsilosis sensu stricto. For the purpose of the study, the isolates were subjected to antifungal susceptibility testing against fluconazole (FLZ), itraconazole (ITZ), voriconazole (VRZ), and two new azole drugs, namely luliconazole (LUZU) and lanoconazole (LZN). The broth microdilution reference method adopted in this study was according to the Clinical & Laboratory Standards Institute M27-A3 and M27-S4 documents.

Results:

According to the results, 89% (n=94) of C. parapsilosis isolates showed a MIC of ≥ 1 µg/ml, indicating resistance against ITZ. Multi-azole resistance was observed in 3.8% of the isolates. In addition, LUZU and LZN demonstrated the highest efficacy with the MIC₅₀ values of 0.5 and 1 µg/ml, respectively.

Conclusion:

The majority of the isolates showed high MIC values against ITZ. This may have been associated with the long-term ITZ prophylaxis/therapy in patients infected with candidiasis. Hence, the adoption of an appropriate antifungal agent is a crucial step for starting the treatment.

Effect of 2-Phenylethanol as Antifungal Agent and Common Antifungals (Amphotericin B, Fluconazole, and Itraconazole) on Candida Species Isolated from Chronic and Recurrent Cases of Candidal Vulvovaginitis

The antifungal effects of 2-phenylethanol are clearly visible through its intervention in Candida morphogenesis. Chronic and recurrent vulvovaginitis, however, does not respond to this standard experimental therapy; therefore, the study presented in this article investigated the effect of common antifungal drugs (amphotericin B [AMB], fluconazole [FLU], and itraconazole [ITC]), in combination with 2-phenylethanol, on the Candida species isolated from cases of chronic and recurrent vulvovaginitis, thereby allowing the recommendation of a more appropriate treatment option. Forty isolates from patients with chronic and recurrent vaginal candidiasis were investigated in this experimental study. The specimens were examined by direct microscopy, culturing, and PCR to identify the species. The antifungal effects of 2-phenylethanol and conventional drugs, both alone and in combination, were determined in duplicate. Finally, the findings were analyzed. In this study, 40 strains of Candida species were identified, whose agents were Candida albicans (95%) and Candida africana (5%). After 48 h, the minimum inhibitory concentration (MIC) range of the 2-phenylethanol was 800-3,200 μg/mL. Also, in the final study on the MIC levels of common antifungal drugs, AMB (0.42 μg/mL) had the lowest MIC, FLU (40.51 μg/mL) had the highest MIC, and the combination of ITC and 2-phenylethanol had the lowest fractional inhibitory concentration index (FICI) of any of the combinations (FICI range, 0.26-1.03). Combining FLU and ITC with 2-phenylethanol can effectively increase their antifungal effect.

Microsatellite Typing and Antifungal Susceptibility of Candida glabrata Strains Isolated From Patients With Candida Vaginitis

Vulvovaginal candidiasis (VVC) is a yeast infection with a global reach and millions of dollars are spent annually for its diagnosis and treatment. Recently, Candida glabrata with different degrees of antifungal resistance has been considered as the second most common cause of vaginal infections. The aim of the present study is to determine the antifungal susceptibility and molecular epidemiology profiles of C. glabrata isolates from patients with VVC. Sixty-one C. glabrata isolates were examined for antifungal susceptibility using the EUCAST broth microdilution method. Moreover, microsatellite length polymorphism (MLP) was used for typing the C. glabrata isolates using six microsatellite markers. Overall, 13, 3.3, and 0% of the isolates were non-wild types to itraconazole, posaconazole, and voriconazole, respectively. Sixty (98.4%) isolates were an intermediate phenotype to fluconazole and only one isolate was fluconazole resistant. Microsatellite length polymorphism with a discriminatory power of 0.964 identified 35 distinct types and 24 singleton genotypes. The assessment of the population genetic structure revealed that the non-wild-type population had a moderate genetic differentiation compared to the wild type population (F_ST = 0.1457). It was also found that the most common genotypes were G27 (eight strains), G12 (six strains), and G4 (five strains). We found that eight strains were resistant/a non-wild phenotype to itraconazole. Five out of eight (62.5%) resistant/non-wild phenotype strains correlated to a predominant genotype (GT27) and the rest belonged to GT11 (12.5%), GT29 (12.5%), and GT28 (12.5%). The current study is the first molecular epidemiology study in the southwest of Iran and demonstrates the antifungal susceptibility profiles of C. glabrata in it. This study shows a wide range of the genetic diversity of C. glabrata (35 different genotypes) from VVC in the southwest of Iran. The majority of the non-wild isolates had a dominant genotype or genotypes related to this dominant genotype (clonal cluster one).

Antifungals susceptibility pattern of Candida spp. isolated from female genital tract at the Yaoundé Bethesda Hospital in Cameroon

Introduction

Vaginal candidiasis is considered as an important public health problem worldwide and its incidence has increased nowadays. In recent years, inappropriate and disproportionate use of antifungal drugs, automedication as well as non compliance have caused drug resistance.

Methods

This study aimed at determining the in vitro antifungal susceptibility patterns of Candida speciesisolated from female genital tract at Yaoundé Bethesda Hospital in Cameroon. Two hundred and fourthy five women (age range: 15 years to 49 years) attending the hospital were recruited between January and June 2014 in this cross sectional study. Vaginal smears were collected using sterile swabs from each participant and cultured on sabouraud dextrose agar supplemented with chloramphenico l 0.5%; identification of Candida spp. was performed following standard methods. The disk diffusion method was used for antifungal susceptibility testing.

Results

Out of the 245 vaginal smears collected, 94 (38.4%) strains of yeast were isolates among which 43 (45.7%) were Candida albicans and 51 (54.3%) were non albicans. The highest susceptibility of the isolates was seen for nystatin 62 (83.78%), ketoconazole 61 (82.43%) and fluconazole 60 (81.08%).

Conclusion

Despite the noticeable resistance of Candida spp. isolates to miconazole and itraconazole, the results indicate that nystatin, ketoconazole and fluconazole are the drugs of choice for the therapy of vaginal candidiasis in this region.

Retrospective observation of drug susceptibility of Candida strains in the years 1999, 2004, and 2015

Introduction

There is much literature devoted to the problem of drug resistance and decreased susceptibility of fungi to commonly used antifungals.

Aim

To analyze drug susceptibility of Candida albicans and non-Candida albicans strains isolated from the hands of people without any symptoms of disease over a 16-year period.

Materials and Methods

The study included a total of 1,274 Candida-type strains isolated from the hands of people without any symptoms of disease, including: in 1999, 432 strains; in 2004, 368; and in 2015, 454 strains. Biological monitoring of hand surface contamination was performed using the Count-Tact^TM applicator with Count-Tact plates (bioMerieux). Drug susceptibility was evaluated using FUNGITEST^®.

Results

In 1999, the most strains showed resistance to fluconazole (53.2%), in 2004 to itraconazole (52.9%), and in 2015 to fluconazole (85.8%). Resistance to more than one drug was 35.8% in 1999, 64.7% in 2004, and 92% in 2015. Mean resistance to azole antifungals significantly increased from 98 ± 39.7 strains in 1999 to 118.3 ± 29.6 in 2015 (p < 0.001). In 1999, the most strains showed resistance to fluconazole (50.6%), in 2004 to itraconazole (52.9%), and in 2015 to fluconazole (44.9%). Resistance to more than one drug was 52.9% in 1999, 64.3% in 2004, and 88.1% in 2015. Mean resistance to azole antifungals significantly increased from a mean of 76 ± 9.7 strains in 1999, to 95.3 ± 24.2 in 2004, and to 97.3 ± 16.6 in 2015 (p < 0.001).

Conclusions

We showed increased C. albicans and non-Candida albicans strain resistance to commonly used antifungal chemotherapeutics, mainly imidazole. We found a clear rise in susceptibility of C. albicans and non-Candida albicans strains to several studied antifungals.

Isolation, molecular identification, and antifungal susceptibility profiles of vaginal isolates of Candida species

BACKGROUND AND OBJECTIVES

Vulvovaginal candidiasis is a common fungal infection among women during reproductive ages. Although, Candida albicans is accounted as the main etiologic agent of vaginitis, non-albicans species have arisen during last years. Resistant to antifungal drugs especially, fluconazole has been more reported by researchers from around the World. The aims of this study were to determine the prevalence of vulvovaginal candidiasis among suspected patients with vaginitis, the frequency of Candida species, and the susceptibility profiles of isolates to caspofungin, fluconazole and clotrimazole.

MATERIALS AND METHODS

One hundred and twenty suspected women with vaginitis were examined by specialist physician and sampled using moisture swabs. Swabs were inoculated on CHROMagar Candida plates, incubated at 35°C and detected all isolated Candida species using morphological, microcopy and molecular methods. The antifungal susceptibility tests with caspofungin, fluconazole and clotrimazole were applied using microdilution and Resazurin dye methods against all isolated yeasts.

RESULTS

The cultures were positive for 34(28.3%) samples and three Candida species including; C. albicans (88.2%), C. glabrata (8.8%) and C. kefyr (2.9%). Our study shows that only one isolate of C. albicans was resistant to caspofungin at the concentration of 2 μg/ml after 24h incubation that increased to 2 isolates after 48h incubation. All isolates were sensitive to fluconazole at the MIC ranges of 1-0.25 μg/ml, while 88.2% of them were inhibited at 0.25 μg/mL of clotrimazole. Candida albicans remains the most common agent of fungal vaginitis.

CONCLUSION

Although all of Candida isolates were susceptible to fluconazole in vitro, it should be used with caution for empirical therapy due to more resistant rates in clinic. In addition, due to valuable sensitivity of all tested strains to caspofungin, it potentially can be presented as the first line therapy for Candida vaginitis.