Intestinal Microbiota in Elderly Inpatients with Clostridioides difficile Infection

Figures & data

Table 1 Clinical Characteristics of Enrolled Subjects, Hospitalized Patients with CDI and Non-CDI Group

Variable	Patients with CDI^a (n=28)	Non-CDI Group (n=56)	P-value
Demographic data
Age (years)^b	79 (68–84)	75 (65–82)	0.971
Female, n (%)	13 (46.42)	24 (42.85)	0.882
BMI (kg/m^2)^b	25.14±3.21	26.28±1.23	0.078
Laboratory data
White blood cells (×10^9 cell/mL) (IQR)	14.4 (9.1–18.8)	9.3 (7.5–11.7)	0.540
Platelets (×10^9 cell/mL)	271 (178–334)	245 (135–291)	0.723
Hemoglobin (mg/L)	11.8 (8.9–13.8)	13.7 (9.2–15.8)	1.02
Albumin (g/dL)	2.8 (2.0–3.1)	2.0 (2.0–2.3)	0.922
Creatinine (mg/dL)	1.36 (0.6–1.50)	0.86 (0.5–1.1)	0.483
Sodium (mg/L)	139 (136–145)	123 (125–136)	0.657
Comorbidities, n (%)
Heart failure	7 (25)	18 (32.1)	0.948
Dementia	2 (7.1)	0	0.986
Respiratory disease	9 (32.1)	11 (19.7)	0.468
Hypertension	3 (10.7)	10 (17.8)	0.756
Cerebrovascular disease	3 (10.7)	12 (21.4)	0.721
Others	4 (14.3)	5 (8.9)	0.990
Antimicrobials and drug administration, n (%)
Clindamycin	18 (64.28)	18 (32)	0.005
Metronidazole	2 (7.14)	1 (1.78)	0.850
Piperacillin/tazobactam	12 (42.85)	10 (17.85)	0.009
Aminoglycosides	11 (39.28)	24 (42.85)	0.128
Cephalosporin	13 (46.42)	15 (26.78)	0.001
Proton pump inhibitors	13 (46.42)	24 (44.64)	0.105
Risk factors
Days of hospitalization, median	29 (16–41)	12 (7–23)	<0.001
Previous surgery within 3 months, n (%)	10 (35.71)	10 (17.85)	<0.001
Residence in nursing home, n (%)	11 (21.15)	4 (8.16)	0.005
Duration of antibiotic exposure	11 (6–18)	5 (4–9)	0.000

Notes: The data are no. (%) of subjects. ^aPatients reported to be CDI positive as they were positive for the microbial culture, the genes encoding tpi gene and the gene encoding toxin B (tcdB) or toxin A (tcdA) genes. ^bValues are presented as mean ± SD.

Abbreviation: IQR, interquartile range.

Table 2 Antimicrobial Susceptibility of 28 Toxigenic C. difficile Isolates

Antimicrobials	Disk Potency	Zone Diameter Values in mm		Number (%) of Isolates
		Susceptible	Resistant	Susceptible	Resistant
Clindamycin^a	(2 µg)	≥15	<15	15 (53.6)	18 (64.2)
Erythromycin^a	(15 µg)	≥22	<17	19 (67.9)	9 (32.1)
Rifampicin^a	(5 µg)	≥20	≤16	26 (92.9)	2 (7.1)
Vancomycin^b	(30 µg)	≥19	<19	26 (92.9)	2 (7.1)
Moxifloxacin^b	(5 µg)	≥21	<18	27 (96.5)	1 (3.5)
Metronidazole^b	(5 µg)	≥15	<15	27 (96.5)	1 (3.5)
Fusidic acid^a	(10 µg)	≥26	≤22	28 (100)	0
Levofloxacin^b	(5 µg)	≥17	≤13	28 (100)	0

Note: ^aClinical and Laboratory Standard Institute; ^bEuropean Committee on Antimicrobial Susceptibility Testing.

Table 3 Minimum Inhibitory Concentrations of 28 Toxigenic Isolates to Vancomycin and Metronidazole

Antimicrobials	MIC (mg/L)			Number (%) of isolates (n=28)
	Range	MIC50	MIC90	Susceptible	Intermediate	Resistant
Vancomycin	0.016–1.5	0.032	0.032	26 (92.8)	2 (7.1)	0
Metronidazole	0.032–2	0.25	0.5	27 (96.4)	1 (3.6)	0

Table 4 Comparison of Population Numbers of Selected Microbial Groups in Case (CDI Patients) and Control (Hospitalized Patients without Diarrhea) Studied Groups Participated in This Study

Bacterial Species	Copies per gram of Faecal Case (N=28) Control (N=56)	t-Test for Equality of Means T Sig. (Two-Tailed)
E. coli	6.65E7±5.38E7 3.16E7±3.92E7	3.30 0.001
Lactobacillus spp.	9.34E7±2.56E8 1.75E7±3.67E7	2.18 0.032
Bacteroides spp.	6.18E7±1.30E8 2.00E8±2.58E8	−2.66 0.009
Clostridium IV	6.25E7±1.05E8 1.95E8±3.25E8	−2.09 0.039
Bifidobacterium spp.	1.41E8±3.86E8 1.56E9±1.92E9	−3.83 0.000
F. prausnitzii	6.91E8±1.33E9 1.29E9±8.55E8	−2.49 0.015
A. muciniphila	7.53E8±1.84E9 2.18E8±2.98E8	2.13 0.036
Klebsiella spp.	6.93E7±7.00E7 3.31E7±5.34E7	2.62 0.010
Enterococcus spp.	5.41E8±1.30E9 4.34E7±5.62E7	2.84 0.006
Prevotella spp.	2.12E7±2.68E7 8.39E8±1.39E9	−3.10 0.003

Figure 1 Box-and-whisker plots of bacterial groups quantified by qPCR. Notes: Bacterial groups quantified by SYBR Green qPCR and expressed as Log10 bacteria per gram stool in hospitalized patients with CDI and non-CDI group. Outlier point were shown by *.

Figure 2 Flow diagram illustrating the number of patients and their gut microbiota patent.