Correlation Between Drug Resistance and Virulence of Candida Isolates from Patients with Candidiasis

Figures & data

Table 1 The Results of the Drug Susceptibility Test of These 53 Strains

Strains	No.	MIC/MEC (µg/mL)
		MCF	TRB	AMB	VRC	ITR
C. albicans: ATCC SC5314 (C1S)	0	<0.015	0.125	0.5	0.03	<0.03
CCJNMM-99	1	0.015	>0.5	0.25	0.03	0.03
CCJNMM-161	3	>8	>0.5	2	1	0.5
CCJNMM-166	4	>8	>0.5	16	16	>16
CCJNMM-328	1	0.0625	>0.5	0.5	<0.03	<0.03
CCJNMM-413	2	<0.015	>0.5	2	<0.03	0.125
CCJNMM-433	2	<0.015	>0.5	2	<0.03	0.5
CCJNMM-435	2	<0.015	>0.5	2	<0.03	0.5
CCJNMM-463	2	0.25	>0.5	0.25	1	1
CCJNMM-511	1	0.03	>0.5	0.5	0.5	0.0625
CCJNMM-514	1	0.015	>0.5	2	0.03	<0.03
CCJNMM-523	3	0.015	>0.5	4	1	0.03
CCJNMM-1504	2	<0.015	>0.5	8	0.125	<0.03
CCJNMM-1516	1	<0.015	0.5	1	0.125	1
CCJNMM-1522	3	1	>0.5	0.25	1	0.0625
CCJNMM-1528	3	0.5	0.5	4	1	0.03
CCJNMM-1551	3	0.015	>0.5	4	1	2
C. tropicalis: CBS 8072 (C2F)	0	<0.015	<0.03	<0.03	0.03	0.015
CCJNMM-32	2	>8	>0.5	2	0.03	0.03
CCJNMM-56	3	>8	>0.5	1	1	0.125
CCJNMM-58	3	>8	>0.5	2	1	0.125
CCJNMM-59	3	2	>0.5	1	4	0.5
CCJNMM-63	2	<0.015	>0.5	1	0.5	2
CCJNMM-70	1	<0.015	0.5	1	0.03	0.5
CCJNMM-71	3	>8	>0.5	1	4	0.25
CCJNMM-106	1	0.015	>0.5	1	<0.03	0.03
CCJNMM-317	1	<0.015	>0.5	0.5	<0.03	<0.03
CCJNMM-323	2	<0.015	>0.5	4	<0.03	0.0625
CCJNMM-354	2	<0.015	>0.5	<0.03	<0.03	1
CCJNMM-402	1	<0.015	>0.5	0.25	<0.03	<0.03
CCJNMM-418	5	>8	>0.5	>16	2	2
CCJNMM-443	2	0.0625	>0.5	2	2	0.125
CCJNMM-518	1	4	0.015	2	0.03	<0.03
CCJNMM-541	3	4	>0.5	2	8	0.5
CCJNMM-570	4	>8	>0.5	0.125	2	16
C. parapsilosis: ATCC 22019 (C4E)	0	0.25	0.001	0.125	<0.03	0.25
CCJNMM-278	1	<0.0625	>0.5	0.25	<0.03	<0.03
CCJNMM-414	1	0.125	>0.5	0.125	<0.03	<0.03
CCJNMM-415	1	0.125	>0.5	1	0.125	0.125
CCJNMM-461	1	0.03	0.0625	1	4	0.25
CCJNMM-471	1	0.5	0.0625	2	0.03	<0.03
CCJNMM-552	2	2	>0.5	2	0.5	0.125
CCJNMM-586	2	0.015	>0.5	2	<0.03	0.03
CCJNMM-600	2	0.015	>0.5	4	<0.03	0.03
CCJNMM-604	2	0.015	>0.5	4	0.03	0.25
CCJNMM-609	2	0.015	>0.5	2	<0.03	0.125
C. glabrata: ATCC2001 (C6G)	0	<0.015	0.0625	0.25	0.0625	0.03
CCJNMM-45	2	0.03	>0.5	16	0.25	0.5
CCJNMM-98	3	0.03	>0.5	>16	16	0.03
CCJNMM-318	1	<0.015	>0.5	1	0.25	0.5
CCJNMM-346	2	<0.015	>0.5	4	0.5	1
CCJNMM-460	2	<0.015	>0.5	1	0.0625	>16
CCJNMM-524	3	0.25	>0.5	0.25	8	0.5

Notes: The results of antifungal susceptibility tests in vitro were observed after 24 hours of incubation. The values of MIC or MEC were read as the lowest drug concentration that prevents any discernible growth. >, the maximum concentration of the antifungal agents which established in antifungal susceptibility tests in vitro still could not inhibit the growth of conidial suspensions; <, the minimum concentration of the antifungal agents which established in antifungal susceptibility tests in vitro can inhibit the growth of conidial suspensions.

Abbreviations: MIC, minimal inhibitory concentration; MEC, minimal effective concentration.

Figure 1 (A, B and C) Gender, ages and department distribution of 206 patients with Candida infection, respectively. (D) Distribution of Candida species in 206 clinical isolates.

Table 2 The Distribution of IC

No.	Age (years)	Sex	Department	Pathogens	Specimens
0069	66	F	ICU	C. tropicalis	Blood
0119	54	M	ICU	C. albicans	Blood
0334	64	F	ICU	C. albicans	Blood
0461	73	M	ICU	C. parapsilosis	Blood
0571	51	F	ICU	C. parapsilosis	Blood
1505	51	M	ICU	C. albicans	Blood
1506	8	M	Pediatrics	C. albicans	Blood
1516	89	M	ICU	C. albicans	Blood
1517	89	M	ICU	C. albicans	Blood
1525	7	F	Pediatrics	C. albicans	Blood
0068	68	M	ICU	C. albicans	Ascites
0102	71	M	ICU	C. parapsilosis	CVC tips

Figure 2 Distribution of diseases involved in 206 patients with Candida infection. (A) a Patients suffering from pulmonary conditions, b Patients suffering from cerebral conditions, c Patients with the history of tumor, d Patients with the history of surgery and trauma, e Patients with other conditions. (B) 206 patients were collected and among them, 101 patients suffered from pulmonary conditions (101/206, 49.03%), 75 patients suffered from cerebral conditions (75/206, 36.41%), 45 patients had the history of tumor (45/206, 21.84%) and 65 patients had the history of surgery and trauma (65/206, 31.55%). (C) The numbers of underlying diseases that patients suffered from. There were 67 patients (67/206, 32.52%) who suffered from 1 underlying disease, 62 patients (62/206, 30.10%) who suffered from 2 underlying diseases, 59 patients (59/206, 28.64%) who suffered from 3 underlying diseases, 15 patients (15/206, 7.28%) who suffered from 4 underlying diseases and 3 patients (3/206, 1.46%) who suffered from 5 underlying diseases.

Table 3 The Distribution of Specimen Sources of 4 Candida Species

Species	Sputum (%) (n=127)	Secretion (%) (n=46)	Urine (%) (n=15)	Blood (%) (n=10)	Others (%) (n=8)	Sum (%) (n=206)
C. albicans	108 (67.92)	32 (20.13)	10 (6.92)	7 (4.40)	2 (1.26)	159 (77.18)
C. tropicalis	12 (42.86)	9 (32.14)	3 (10.71)	1 (3.57)	3 (10.71)	28 (13.59)
C. glabrata	2 (33.33)	4 (66.66)	0 (0.00)	0 (0.00)	0 (0.00)	6 (2.91)
C. parapsilosis	5 (38.46)	1 (7.69)	2 (15.38)	2 (15.38)	3 (23.08)	13 (6.31)

Table 4 Results of Two Identification Methods

Species	No. of Agreement	No. of Misjudgment	Correct Rate (%)
C. albicans (n=159)	149	10	93.71
C. tropicalis (n=28)	24	4	85.71
C. glabrata (n=6)	5	1	83.33
C. parapsilosis (n=13)	13	0	100.00
Total (n=206)	191	15	92.72

Table 5 Ranges of MIC/MEC, MIC₅₀/MIC₉₀ and Susceptibility Category of 5 Antifungal Agents Against 206 Candida Isolates

Species (n)	Antifigual Agent	MICs/MECs (mg/L)		No. of Isolates in Each Indicated Susceptibility Category by CBP or ECV
		Range	MIC50/MIC90	S (%)	I (%)	R (%)	WT (%)	Non-WT (%)
C. albicans (159)	MCF	0.015–8	0.015/0.125	150 (94.34)	1 (0.63)	8 (5.03)
	TRB	0.03–0.5	0.5/0.5				19 (11.95)	140 (88.05)
	AMB	0.03–16	2/16				86 (54.09)	73 (45.91)
	VRC	0.03–16	0.03/1	119 (74.84)	12 (7.55)	28 (17.61)
	ITR	0.03–16	0.03/1
C. tropicalis (28)	MCF	0.015–8	0.25/8	14 (50.00)	0	14 (50.00)
	TRB	0.015–0.5	0.5/0.5				5 (17.86)	23 (82.14)
	AMB	0.03–16	1/4				24 (85.1)	4 (14.29)
	VRC	0.03–8	0.03/4	18 (64.29)	3 (10.71)	7 (25.00)
	ITR	0.125–1	0.03/16				25 (89.29)	3 (10.71)
C. glabrata (6)	MCF	0.015–0.25	0.015/0.25	5 (83.33)	0	1 (16.67)
	TRB	0.5	0.5/0.5				6 (100.00)	0
	AMB	0.25–16	1/16				4 (66.67)	2 (33.33)
	VRC	0.0625–16	0.25/16	–	–	–	–	–
	ITR	0.03–16	0.5/16				5 (83.33)	1 (16.67)
C. parapsilosis (13)	MCF	0.015–2	0.0625/0.5	13 (100.00)	0	0
	TRB	0.015–0.5	0.5/0.5				5 (38.46)	8 (61.54)
	AMB	0.125–4	1/2				7 (53.85)	6 (46.15)
	VRC	0.03–4	0.03/0.5	11 (84.62)	1 (7.69)	1 (7.69)
	ITR	0.03–0.25	0.03/0.25				13 (100.00)	0

Abbreviations: –, not defined; AMB, Amphotericin B; CBP, Clinical Breakpoints; ECV, Epidemiological Cutoff Value; I, Intermediate; ITR Itraconazole; MCF Micafungin; MEC, Minimal Effective Concentration; MIC, Minimal Inhibitory Concentration; MIC₅₀, the concentration at which 50% of the growth of conidial suspensions could be inhibited; MIC₉₀, the concentration at which 90% of the growth of conidial suspensions could be inhibited; Range, the 24-hour microdilution MIC/MEC range; R, Resistant; S, Susceptible; TRB Terbinafine; VRC Voriconazole; WT, Wild-type; non-WT, non-Wild-type.

Figure 3 (A) Fungal burden at different times of the strain C1S showed that the fungal load was not high when sampling at 2 h, but on the 1st or 3rd day, the number of high-concentration spores injected into the SDA plate showed more yeast-like colonies. On the 7th day, fungal burden was not observed on the SDA plate. (B and C) C. albicans (C1S, 511 and 166) and C. tropicalis (C2F, 402 and 418) had the same trend as C1S.

Figure 4 The mortality of G. mellonella larvae enhanced with strain concentration. The results of these following strains include C. albicans (C1S, 511 and 166), C. tropicalis (C2F, 402 and 418), C. parapsilosis (C4E, 278 and 604) and C. glabrata (C6G, 318 and 524).

Figure 5 For C. albicans, C. tropicalis, C. parapsilosis or C. glabrata, there was no significant difference in median lethal dose (LD₅₀) of G. mellonella larvae among infection models of multiple-drug resistant strains, single-drug resistant strains and non-drug resistant standard strains. But the difference among these four candida species was statistically significant (P<0.001).