Genotyping and Drug Resistance Profile of Clinical Isolates of Candida Albicans From Vulvovaginal Candidiasis in The Eastern China

doi:10.21203/rs.3.rs-976834/v1

A total of 244 Candida albicans isolates recovered from VVC patients in Suzhou, Eastern China, were investigated. According to CLSI documents M27-A4 and M59-3ed / M60-2ed, the geometric mean MICs of nine antifungals in increasing order were micafungin(0.048mg/L), anidulafungin (0.132mg/L), caspofungin (0.19mg/L), itraconazole(0.23mg/L), posaconazole(0.25mg/L), voriconazole(0.28mg/L), 5-flucytosine (0.44mg/L), amphotericin B (0.49mg/L) and fluconazole (2.01 mg/L) respectively. Of note, 6.5% (16/244) C. albicans isolates showed resistance mainly to anidulafungin (mono-echinocandin resistance), while voriconazole had the lowest susceptibility rate of 34.8% (85/244), followed by fluconazole 59.4% (145/244), respectively. All isolates were genotyped by allelic combination of 3 microsatellite markers (CEF3, CAIII and LOC4). A total of 129 different allelic genotypes were identified, in which seven different clades were recognized with a discriminatory power of 0.96. Genotype A-D were present in 35% of the isolates. In conclusion, decrease of antifungal drug susceptibility to C. albicans isolates from VVC is alarming. Our findings revealed the genetic diversity of C. albicans isolates among VVC patients and provided insights into the molecular epidemiology of Candida infections in China.

Mycology

General Microbiology

Genetic diversity

antifungal susceptibility

resistance

Candida albicans

vulvovaginal candidiasis

China

Vulvovaginal candidiasis (VVC) is one of the most common vaginitis that caused by Candida albicans, which accounts for 80–95% of all episodes of VVC worldwide, though the number of non-albicans species (such as C. glabrata) are increasing as etiological agents of VVC[1, 2]. An increasing prevalence of fungal resistance is also reported in antifungal surveillance studies globally[3–5]. Antifungal susceptibility testing of C. albicans isolates therefore plays a crucial role for appropriate and effective management strategies of VVC [5]. In addition, it is important to look into the population genetic characteristics of C. albicans infections owing to increasing reports indicating dynamic antifungal susceptibility profile with different genotype and geographic origin[6]. Thus, understanding the genetic diversity of C. albicans could help clinicians to implement appropriate diagnostic, therapeutic and preventive strategies[7, 8]. Microsatellite marker is highly reproducible with strong discriminatory potential and is widely applied in molecular typing [9]. In previous studies, microsatellite analysis has proved itself to be a powerful tool in investigating the relationship between genetic diversity and antifungal susceptibility of C. albicans isolates [10, 11]. However, population genetic and antifungal susceptibility profile of isolates from VVC patients in China still remain fragmented and limited. Therefore, in this study, we investigated the antifungal susceptibility profile based on M27-A4 and M59/M60 documents approved in 2020 for interpretive breakpoints and ECV, and performed molecular typing utilizing three microsatellite loci (CAIII, CEF3, and LOC) on a hundreds of C. albicans isolates from VVC patients in eastern China (Suzhou area).

Isolates and Identification

A total of 244 vaginal C. albicans isolates were recovered from patients with Vulvovaginal candidiasis in the People's hospital of Suzhou New District during 2018 in this study. The patients and case definition, vaginal samples collecting information have been reported in previous publication[5]. All isolates were identified to the species level by sequencing 26S ribosomal DNA gene D1/D2 domains as described previously[5]. Isolates information and GenBank accession numbers of D1/D2 sequences are listed in Supplementary table1.

Microsatellite analysis

Microsatellite genotyping was performed on all 244 C. albicans isolates, with a panel of three different short-nucleotide repeat fragments, using fluorescently labeled primers CAIII (5-Tamra -TTGGAATCACTTCACCAGGA-3, 5-TTTCCGTGGCATCAGTATCA-3); CEF3 (5- Hex-TTTCCTCTTCCTTTCATATAGAA-3, 5- GGATTCACTAGCAGCAGACA-3); LOC4 (5- FAM –GTAATGATTACGGCAATGAC-3, 5-AGAACGACGTGTACTATTGG-3)[11]. A multiplex polymerase chain reaction (PCR) was performed in 10μl reaction volumes containing 5μl of Qiagen Multiplex PCR (2x, Lot 148031955), 0.25μl of each primer (F+R), 3μl of ddH2O, and 1μl of genomic DNA. PCR amplifications were performed in a thermocycler (BOECO, TC-Pro, Germany) operated with a temperature-cycling program that consisted of an initial denaturing step at 95◦C for 15 min, followed by 35 cycles of 30 s at 94◦C, 90 s at 57◦C, and 60 s at 72◦C. The final extension step was for 10 min at 72◦C. The sizes of the fragments were determined by addition of the GeneScan LIZ [500] marker and subsequent analysis of the fragments on the Applied Biosystems 3730 DNA analyzer. Assignment of repeat numbers in each marker was determined from the GeneScan data by using the Peak GeneMapper5.0 software (Applied Biosystems, Foster City, CA, USA). The sizes of the fragments were determined based on the LIZ500 marker, Allele-sharing distance matrices were generated from the tandem repeat numbers and were used as input for UPGMA clustering analysis. The UPGMA clustering of the 244 C. albicans isolates was performed using R package phangorn. The UPGMA tree was then plotted using R (version 3.4.4). The discrimination power (DP) of the microsatellite genotyping method used in this study, which calculates the probability of any pair of isolates to have different genotypes, was calculated by the online calculator created by the university of the basque country (http://insilico.ehu.es/mini_tools/discriminatory_power).

Antifungal Susceptibility Testing

All isolates were tested for in vitro antifungal susceptibility to 9 antifungal agents according to the CLSI reference guideline M27-A4[12]. Antifungal drugs tested were anidulafungin (ANF), caspofungin (CAS), micafungin (MFG), amphotericin B (AmB), 5-flucytosine (5-FC), fluconazole (FLC), itraconazole (ITC), voriconazole (VRC), posaconazole(POS). Anidulafungin, and voriconazole were purchased from Toronto Research Chemicals Inc,Canada, micafungin was provided by Astellas Pharma,Japan, and remaining antifungals were obtained from Sigma-Aldrich. C. parapsilosis ATCC 22019 and C. krusei ATCC 6258 were used as control strains in all experiments. All isolates were sub-cultured onto Sabouraud Dextrose Agar at 35 ℃ for 24h for viability and purity. Colonies were suspended in sterile saline, and the final inoculum concentration of the suspension was adjusted to 0.5-2.5 x 10³ CFU mL^-1 with RPMI1640 broth medium. The 96-well plates were incubated for 24 or 48 h at 35℃, and minimum inhibitory concentrations (MIC) were determined visually. Drug concentration ranges, time of MIC reading and interpretive breakpoints used for 9 antifungal agents are listed in Supplementary table 2.

Interpretation of MIC results

Interpretation of susceptibility was performed by applying the clinical breakpoints (CBPs) defined by the document M60-2ed[13]. In the absence of CBPs, isolates were defined as having a wild-type (WT) or a non-wild-type (NWT) drug susceptibility phenotype (to amphotericin B, posaconazole, itraconazole and 5-flucytosine) according to the epidemiological cutoff values (ECV)defined by the document M59-3ed[14], as shown in Supplementary table 2.

Ethical statement

Ethical approval and patient consensus were not considered necessary due to the descriptive nature of the study that implied only the samples obtained during routine laboratory activity.

Table 1 summarized the antifungal susceptibility profile of 244 C. albicans isolates to 9 antifungals. The Geometric Mean MIC of the antifungals across all isolates were the following (in increasing order): micafungin(0.048mg/L), anidulafungin(0.132mg/L), caspofungin(0.19mg/L), itraconazole(0.23mg/L), posaconazole(0.25mg/L), voriconazole(0.28mg/L), 5-flucytosine (0.44mg/L), amphotericine B (0.49mg/L) and fluconazole (2.01mg/L).

Table 1．Antifungal susceptibility profile of 244 C. albicans isolates from VVC to 9 antifungal agents.

Drug	Range	MIC₅₀/ MIC₉₀	GM	S(%)	I (%)	SDD (%)	R (%)	NWT (%)
MFG	0.016-1	0.0313/0.25	0.048	227/93.0%	15/6.2%	NA	2/0.8%	NA
ANF	0.016-4	0.125/0.5	0.132	210/86.1%	18/7.4%	NA	16/6.5%	NA
CAS	0.0313-1	0.25/0.25	0.191	222/91.0%	21/8.6%	NA	1/0.4%	NA
FLC	0.125-64	2/16	2.011	145/59.4% NA		36/14.8%	63/25.8%	NA
VRC	0.125-4	0.25/1	0.278	85/34.8%	126/51.6%	NA	33/13.5%	NA
POS	0.0313-4	0.25/1	0.251	NA^a	NA	NA	NA	221 / 90.5%
ITR	0.0313-16	0.25/1	0.232	NA	NA	NA	NA	NA
AmB	0.25-1	0.5/0.5	0.485	NA	NA	NA	NA	0/0%
5-FC	0.125-64	0.25/2	0.436	NA	NA	NA	NA	NA

Note: a: not applicable; GM: geometric mean values; S%: susceptible rate; I%: intermediate susceptible rate; SDD%: susceptible dose dependent rate; R%: resistant rate; NWT%: rate of non-wild type.

Table 2 summarized MIC distribution, R% and NWT% of 244 C. albicans isolates from VVC to 9 antifungal agents. Of the 244 C. albicans isolates, 86% (210/244) - 93% (227/224) isolates were susceptible to the three echinocandins tested, and 6.5% of the C. albicans isolates were resistant to anidulafungin which was much higher than those of two other echinocandins tested (0.4% and 0.8%, respectively).

Table 2.MIC distribution, R%, NWT% of 244 C. albicans isolates from VVC to 9 antifungal agents.

Drug	0.016	0.0313	0.0625	0.125	0.25	0.5	1	2	4	8	16	32	≥64	R%	NWT%
MFG	16.4	61.5^a	80.7	87.3	93.0^b	99.2	100.0	100.0	100.0	100.0	100.0	100.0	100.0	0.8%	38.50%
ANF	3.3	8.2	37.3	67.6	86.1	93.4	97.1	99.2	100.0	100.0	100.0	100.0	100.0	6.5%	32.4%
CAS	0.0	2.9	10.7	34.4	91.0	99.2	100.0	100.0	100.0	100.0	100.0	100.0	100.0	0.4%	NA
FLC	0.0	0.0	0.0	5.7	13.9	25.4	42.6	59.4	74.2	86.1	92.2	99.6	100.0	25.8%	74.6%
VRC	0.0	0.0	0.0	34.8	66.0	86.5	98.0	99.2	100.0	100.0	100.0	100.0	100.0	13.5%	100%
POS	0.0	5.3	23.0	42.2	59.4	81.6	90.2	97.5	100.0	100.0	100.0	100.0	100.0	NA^c	90.5%
ITR	0.0	14.8	24.2	39.8	60.2	84.4	93.0	95.9	98.8	99.6	100.0	100.0	100.0	NA	NA
AmB	0.0	0.0	0.0	0.0	11.5	93.0	100.0	100.0	100.0	100.0	100.0	100.0	100.0	NA	0
5-FC	0.0	0.0	0.0	35.7	51.6	66.0	76.2	95.5	98.0	98.8	99.2	98.2	100.0	NA	NA

Note: a: percentage of isolates with MIC≦ECV; b: percentage of isolates with MIC≦susceptible CBP; c: not applicable; R%: resistant rate; NWT%: rate of non-wild type

The in vitro activity of triazoles against 244 isolates of C. albicans was variable; Fluconazole was active against 59.4% (145/244) isolates tested, and 25.8% (63/244) of the C. albicans isolates were fluconazole resistant. However, 14.8% (36/244) of the isolates were fluconazole SDD. Voriconazole had reduced activity to approximately more than half of the isolates with susceptibility rate 34.8% (85/244), whereas 51.6% (126/244) isolates were intermediate susceptibility and13.5% (33/244) were resistant to voriconazole. Resistance to both fluconazole and voriconazole were found in 23 isolate of C. albicans. However, 90.5% isolates of the C. albicans showed relatively higher MICs than epidemiological cutoff value (ECV 0.06 mg/L) to posaconazole, when testing the susceptibility to itraconazole, 60.2% isolates had MICs value >0.125 mg/L, and 15.6% isolates had MICs value>0.5mg/L.

As expected, all C. albicans isolates tested revealed lower MICs than ECV (2 mg/L) to amphotericin B, while 98.0% of isolates showed lower MIC than 4mg/L to 5-flucytosine.

The genotypic relationship of 244 C. albicans isolates from VVC patients was determined based on UPGMA analysis of 3 microsatellite markers CEF3, CAIII, LOC4 . Seven different clades were recognized (Figure 1). Microsatellite genotyping of three loci showed considerable diversity among 244 C. albicans isolates, and 129 different allelic combinations were identified among 244 unrelated C. albicans isolates with 108 singleton genotypes. The combined discriminatory power (DP) of the 3-loci (CAIII, CEF3, and LOC4) typing method was 0.96. The most frequent genotype was genotype A (34/244, 13.9%) followed by genotype B (25/244, 10%) and C (18/244, 7%), respectively. The other remaining genotypes had a frequency less than 5%（Supplementary table 1）.

This study investigated the antifungal susceptibility profile and genetic diversity of 244 C. albicans isolates from VVC patients in Suzhou, eastern China.

The majority of C. albicans isolates in this study showed good antifungal activity to the three echinocandins. Micafungin (MIC₅₀/MIC₉₀: 0.031/0.25mg/L) showed slightly higher potency than caspofungin (MIC₅₀/MIC₉₀: 0.25/0.25 mg/L) and anidulafungin (MIC₅₀/MIC₉₀: 0.125/0.5 mg/L) which were consistent with previous studies[5, 15]. Of note, less than 10% C. albicans isolates was found to have intermediate susceptibility to three echinocandins tested, whereas 16 in 244 (6.5%) C. albicans isolates showed resistant mainly to anidulafungin(mono-echinocandin resistance), furthermore, of the 16 isolates of C. albicans with high-MIC anidulafungin phenotype(MICs≧1 mg/L), only one isolate had MICs≧1 mg/L for micafungin, and another one isolate had MICs≧1 mg/L for caspofungin, which is not in agreement with those reported previously that C. albicans resistant to echinocandins accounted for less than <1% [6, 16] and the mono-echinocandin resistance phenotype was rare[17, 18]. However, our previous study reported one isolate with MIC 1mg/L for anidulafungin among 207 C. albicans isolates from VVC patients in western China[5]. Pfaller et al. presented similar results on anidulafungin against C. albicans causing invasive infections [19]. Lindberg et al.[20] determined the in vitro susceptibility of Candida isolates from the blood samples of patients with candidemia at a Swedish hospital and found that 17% C. albicans isolates were not susceptible to anidulafungin by applying the EUCAST CBPs, however, when the CLSI CBPs were applied, all the isolates exhibited susceptibility to anidulafungin. Thus, isolates with this high anidulafungin MIC warrant further study.

All triazoles tested had reduced activity against C. albicans isolates from VVC patients. Voriconazole had the lowest susceptibility rate of 34.8% (85/244), followed by fluconazole 59.4% (145/244), respectively. Of note, about half of C. albicans isolates (51.6%) tested were classified as intermediate susceptibility to voriconazole, whereas 25.8%, 13.5% of the isolates were resistant to fluconazole and voriconazole, respectively. Compared to our previous study in western China[5], fluconazole resistance of C. albicans isolates from VVC significantly increased in eastern China (8.2% Resistaant rate in western China versus 25.8% Resistaant rate in Suzhou, eastern China). Our results were also compatible with the most Chinese reports which presented approximately half isolates of C. albicans causing VVC were susceptible to fluconazole [21-23]. Notably, percentage of isolates on resistance and I/SDD to fluconazole and voriconazole in Suzhou are much higher than those in previous reports from Dota KFD et al.[15], Ying C et al.[21] and Shi et al.[23].

The MIC values for posaconazole in present study were overall high with 90.5% NWT isolates which was higher than 60% NWT isolates found in our previous study in west area when the CLSI ECV (0.06mg/L) was applied. Our findings is contrary to those from northern America[24] and Kuwait[25] which showed good activity of posaconazole against C. albicans isolates from VVC (MIC₉₀: 0.03mg/L and 0.064 mg/L, respectively). However, 37.6% NWT isolates to posaconazole were reported from invasive candidiasis[26]. Although no interpretive breakpoint for itraconazole to C. albicans based on the newly described CLSI breakpoints[13, 14], it must be recognized as distinctly unusual, given that 60% isolates had MICs value >0.125 mg/L, and 15.6% (38/244)isolates had MICs value≧1mg/L(Table 2). Overall, resistance to triazoles among C. albicans isolates was found to have increasing significantly with time. It could be associated with relatively high frequency use of those azoles in clinical settings in Suzhou area[27], Therefore, continued surveillance on changes of antifungal susceptibility are necessary to guide treatment of VVC.

Microsatellite genotyping of three loci showed considerably high diversity, and 129 different allelic combinations were identified among 244 isolates of C. albicans recovered from patients with VVC. We observed that the dominant genotype A-C (77/244) accounted for 31.5 % of the isolates, however, a total of 108 isolates were shown to represent unique molecular type which account for 44% isolates tested, indicating high genetic diversity within the isolates in this study (Supplementary table 1). Seven clades were recognizable based on a categorical analysis of CEF3, CAIII, LOC4 microsatellite markers in combination with UPGMA clustering (Fig.1). Our results confirmed high genetic diversity among C. albicans isolates which is consistent with previous studies[10, 11]. The relatively high genetic variability among C. albicans samples may be related to high dynamism of the C. albicans genome with frequent translocations, deletions, and duplications.

Drug resistances of C. albicans presents significant challenges to implement appropriate therapies and treatment for VVC. Therefore, antifungal susceptibility testing of Candida isolates plays a crucial role in the management of Candida infections. The microsatellite data of C. albicans, confirmed that this medically important yeast has maintained high levels of genetic diversity in Eastern China.

Author Contributions: Conceptualization, N.H., N.Y. & SW.D.; Methodology, Y.L., L.Y, H.Z., R.F., DY.H., G.W. & XF. C.; data analysis, N.H. & H.C.; writing—original draft preparation, SW.D., N.H. & N.Y.; writing—review and editing, SW.D. & H.C.; visualization, D.H. & H.C; supervision, WQ.L. & SW.D. All authors have read and agreed to the published version of the manuscript.

Funding: This study were funded by from Suzhou Health and Family Planning Commission (LCZX201728), Suzhou New District (2017Z008) to Shuwen Deng; partly by two projects of National Natural Science Foundation of China (82102419 and 81720108026) and Innovation Team Foundation of Jiangsu Province (grant number CXTDA2017038).

Data Availability Statement: Sequence data used in this study was available in Genbank under accession number MZ172462-MZ172702 and MZ226435-MZ226437.

Acknowledgments: N.H., Y.L. and H.C. contributed equally to this work and should share the first co-authorship.

Conflicts of Interest: The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

Mendling W, Brasch J, Cornely OA, Effendy I, Friese K, Ginter-Hanselmayer G, Hof H, Mayser P, Mylonas I, Ruhnke M, Schaller M, and E. R. Weissenbacher. "Guideline: Vulvovaginal Candidosis (Awmf 015/072), S2k (Excluding Chronic Mucocutaneous Candidosis)." Mycoses 58 Suppl 1 (2015): 1-15.
Achkar JM. and B. C. Fries. "Candida Infections of the Genitourinary Tract.". Clin Microbiol Rev. 2010;23(2):253–73.
Nagashima M, Yamagishi Y, Mikamo H. Antifungal Susceptibilities of Candida Species Isolated from the Patients with Vaginal Candidiasis. J Infect Chemother. 2016;22(2):124–6.
Richter SS, Galask RP, Messer SA, Hollis RJ, Diekema DJ. and M. A. Pfaller. "Antifungal Susceptibilities of Candida Species Causing Vulvovaginitis and Epidemiology of Recurrent Cases.". J Clin Microbiol. 2005;43(5):2155–62.
Yan L, Wang XD, Seyedmousavi S, Yuan JN, Abulize P, Pan WH, Yu N, Yang YL, Hu HQ, Liao WQ, and S. W. Deng. "Antifungal Susceptibility Profile of Candida Albicans Isolated from Vulvovaginal Candidiasis in Xinjiang Province of China." Mycopathologia 184, no. 3 (2019): 413-22.
Arendrup MC, Dzajic E, Jensen RH, Johansen HK, Kjaeldgaard P, Knudsen JD, Kristensen L, Leitz C, Lemming LE, Nielsen L, Olesen B, Rosenvinge FS, Røder BL. and H. C. Schønheyder. "Epidemiological Changes with Potential Implication for Antifungal Prescription Recommendations for Fungaemia: Data from a Nationwide Fungaemia Surveillance Programme.". Clin Microbiol Infect. 2013;19:no. 8. E343-53.
Adjapong G, Hale M, Garrill A. Population Structure of Candida Albicans from Three Teaching Hospitals in Ghana. Med Mycol. 2016;54(2):197–206.
Ge SH, Wan Z, Li J, Xu J, Li RY, Bai FY. "Correlation between Azole Susceptibilities, Genotypes, and Erg11 Mutations in Candida Albicans Isolates Associated with Vulvovaginal Candidiasis in China.". Antimicrob Agents Chemother. 2010;54(8):3126–31.
Sampaio P, Gusmão L, Correia A, Alves C, Rodrigues AG, Pina-Vaz C, Amorim A, Pais C. "New Microsatellite Multiplex Pcr for Candida Albicans Strain Typing Reveals Microevolutionary Changes.". J Clin Microbiol. 2005;43(8):3869–76.
Güzel AB, Döğen A, Aydın M, Serin A, Serin MS, Kalkancı A, Ilkit M. "Genotyping Reveals No Link between Candida Albicans Genotype and Vaginitis Severity in Turkish Women." Mycopathologia 175, no. 3-4 (2013): 287-94.
Sharifynia S, Rezaie S, Mohamadnia A, Mortezaee V, Hadian A, Seyedmousavi S. "Genetic Diversity and Antifungal Susceptibility of Candida Albicans Isolated from Iranian Patients. " Med Mycol. 2019;57(1):127–31.
Clinical and Laboratory Standards Institute. Reference Method for Broth Dilution Antifungal Susceptibility Testing of Yeasts, 4rd edition; Document M27-A4. 2017.
Clinical and Laboratory Standards Institute. Reference Method for Broth Dilution Antifungal Susceptibility Testing of Yeasts: Performance Standards for Antifungal Susceptibility Testing of Yeasts, M60 2nd Edition, 2020.
Clinical and Laboratory Standards Institute. Epidemiological Cutoff Values for Antifungal Susceptibility Testing, M59 3nd Edition, 2020.
Boikov DA, Locke JB, James KD, Bartizal K, Sobel JD. "In Vitro Activity of the Novel Echinocandin Cd101 at Ph 7 and 4 against Candida Spp. Isolates from Patients with Vulvovaginal Candidiasis.". J Antimicrob Chemother. 2017;72(5):1355–58.
de Aquino Lemos J, Costa CR, de Araújo CR, Souza LK, Silva Mdo R. "Susceptibility Testing of Candida Albicans Isolated from Oropharyngeal Mucosa of Hiv(+) Patients to Fluconazole, Amphotericin B and Caspofungin. Killing Kinetics of Caspofungin and Amphotericin B against Fluconazole Resistant and Susceptible Isolates.". Braz J Microbiol. 2009;40(1):163–9.
Arendrup MC, Perlin DS. "Echinocandin Resistance: An Emerging Clinical Problem?". Curr Opin Infect Dis. 2014;27(6):484–92.
Siopi M, Tarpatzi A, Kalogeropoulou E, Damianidou S, Vasilakopoulou A, Vourli S, Pournaras S, Meletiadis J. "Epidemiological Trends of Fungemia in Greece with a Focus on Candidemia During the Recent Financial Crisis: A 10-Year Survey in a Tertiary Care Academic Hospital and Review of Literature." Antimicrob Agents Chemother 64, no. 3 (2020).
Pfaller MA, Boyken L, Hollis RJ, Kroeger J, Messer SA, Tendolkar S, Diekema DJ. "In Vitro Susceptibility of Invasive Isolates of Candida Spp. To Anidulafungin, Caspofungin, and Micafungin: Six Years of Global Surveillance.". J Clin Microbiol. 2008;46(1):150–6.
Lindberg E, Hammarström H, Ataollahy N, Kondori N. Species Distribution and Antifungal Drug Susceptibilities of Yeasts Isolated from the Blood Samples of Patients with Candidemia. Sci Rep. 2019;9(1):3838.
Ying C, Zhang H, Tang Z, Chen H, Gao J, Yue C. Antifungal Susceptibility and Molecular Typing of 115 Candida Albicans Isolates Obtained from Vulvovaginal Candidiasis Patients in 3 Shanghai Maternity Hospitals. Med Mycol. 2016;54(4):394–9.
Liu XP, Fan SR, Peng YT, Zhang HP. Species Distribution and Susceptibility of Candida Isolates from Patient with Vulvovaginal Candidiasis in Southern China from 2003 to 2012. J Mycol Med. 2014;24(2):106–11.
Shi XY, Yang YP, Zhang Y, Li W, Wang JD, Huang WM, Fan YM. "Molecular Identification and Antifungal Susceptibility of 186 Candida Isolates from Vulvovaginal Candidiasis in Southern China.". J Med Microbiol. 2015;64:390–93. no. Pt 4 ).
Danby CS, Boikov D, Rautemaa-Richardson R, Sobel JD. "Effect of Ph on in Vitro Susceptibility of Candida Glabrata and Candida Albicans to 11 Antifungal Agents and Implications for Clinical Use.". Antimicrob Agents Chemother. 2012;56(3):1403–6.
Alfouzan W, Dhar R, Ashkanani H, Gupta M, Rachel C, Khan ZU. Species Spectrum and Antifungal Susceptibility Profile of Vaginal Isolates of Candida in Kuwait. J Mycol Med. 2015;25(1):23–8.
Noni M, Stathi A, Vaki I, Velegraki A, Zachariadou L, Michos A. "Changing Epidemiology of Invasive Candidiasis in Children During a 10-Year Period." J Fungi (Basel) 5, no. 1 (2019).
Lin XY, Wang SL, Duan XL, Lan CG, Chen XJ, Xue J, Yang Y. "Review of Clinical Experience in Itraconazole Therapy for 10 Years in China.". J Clin Dermatol. 2003;32(7):429–30.

Supplementarytable1.docx
Supplementary table 1: The isolates information and GenBank accession numbers for 244 C. albicans isolates tested in this study;
Supplementarytable2.docx
Supplementary table 2: Drug concentration range, time of MIC reading and interpretive breakpoints for 9 antifungal agents used in this study.

Genotyping and Drug Resistance Profile of Clinical Isolates of Candida Albicans From Vulvovaginal Candidiasis in The Eastern China

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Introduction

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