Identification and characterization of bacteria isolated from patients with cystic fibrosis in Jordan

Figures & data

Figure 1. Prevalence of bacterial strains (number and percentage) isolated from patients with cystic fibrosis enrolled in the study.

Table 2. Antibiotic susceptibility percent of isolated bacteria from patients with cystic fibrosis enrolled in the study.

Bacteria antibiotics	Gram-negative bacteria						Gram-positive bacteria
	P. aeruginosa, % (n)	P. pseudoalcaligenes, % (n)	P. fluorescens, % (n)	P. mendocina, % (n)	S. marcescens, % (n)	E. coli, % (n)	S. aureus, % (n)	S. agalactiae, % (n)
CAZ	100 (17)	100 (1)	100 (1)	100 (1)	100 (2)	100 (2)	–	–
TOB	88.2 (15)	100 (1)	100 (1)	100 (1)	100 (2)	50 (1)	–	–
TZP	100 (17)	100 (1)	100 (1)	100 (1)	100 (2)	100 (2)	–	–
IPM	88.2 (15)	100 (1)	100 (1)	100 (1)	100 (2)	100 (2)	–	–
ATM	94.11 (16)	100 (1)	100 (1)	100 (1)	50 (1)	100 (2)	–	–
AK	82.35 (14)	100 (1)	100 (1)	100 (1)	100 (2)	100 (2)	–	–
LEV	100 (17)	100 (1)	100 (1)	100 (1)	50 (1)	50 (1)	–	0
MEM	94.11 (16)	100 (1)	100 (1)	100 (1)	100 (2)	100 (2)	–	100 (1)
FEP	100 (17)	100 (1)	100 (1)	100 (1)	100 (2)	100 (2)	–	100 (1)
CIP	94.11 (16)	100 (1)	100 (1)	100 (1)	50 (1)	50 (1)	94.4 (17)	–
CN	88.2 (15)	100 (1)	100 (1)	100 (1)	100 (2)	100 (1)	100 (18)	0 (0)
(P)	–	–	–	–	–	–	11.11 (4)	–
RA	–	–	–	–	–	–	88.88 (16)	0 (0)
DA	–	–	–	–	–	–	77.77 (14)	0 (0)
E	–	–	–	–	–	–	16.66 (15)	0 (0)
OX	–	–	–	–	–	–	33.33 (6)	–
DO	–	–	–	–	–	–	100 (18)	–
SXT	–	–	–	–	–	–	100 (18)	–
AZM	–	–	–	–	–	–	–	0 (0)
AM	–	–	–	–	–	–	–	0 (0)
OFX	–	–	–	–	–	–	–	0 (0)
TE	–	–	–	–	–	–	–	0 (0)
C	–	–	–	–	–	–	–	100 (1)
VA	–	–	–	–	–	–	–	0 (0)

Abbreviations. CAZ: ceftazidime; TOB: tobramycin; TZP: piperacillin-tazobactam; IPM; imipenem; ATM: aztreonam; AK: amikacin; LEV: levofloxacin; MEM: meropenem; FEP: cefepime; CIP: ciprofloxacin; CN: gentamicin; P: penicillin; RA: rifampin; DA: clindamycin; E: erythromycin; OX: oxacillin; DO: doxycycline; SXT: trimethoprim-sulfamethoxazole; AZM: azithromycin; AM: ampicillin; OFX: ofloxacin; TE: tetracycline; C: chloramphenicol; VA: vancomycin; –: not tested.

Table 3. Biofilm formation profile of bacteria isolated from patients with cystic fibrosis enrolled in the study.

Bacterial isolates	Biofilm formation patterns
	Strong biofilm formers, n (%)	Moderate biofilm formers, n (%)	Weak biofilm formers, n (%)	Non biofilm producer, n (%)
Staphylococcus aureus	0 (0)	6 (33.33)	12 (66.66)	0 (0)
Pseudomonas aeruginosa	8 (47)	4 (23.5)	5 (29.4)	0 (0)
P. pseudoalcaligenes	1 (100)	0 (0)	0 (0)	0 (0)
S. marcescens	0 (0)	0 (0)	2 (100)	0 (0)
E. coli	0 (0)	0 (0)	1 (50)	1 (50)
S. agalactiae	0 (0)	0 (0)	1 (100)	0 (0)
P. fluorescens	0 (0)	0 (0)	1 (100)	0 (0)
P. mendocina	1 (100)	0 (0)	0 (0)	0 (0)
Total	10 (23.26)	10 (23.26)	22 (51.16)	1 (2.33)

Table 4. MBEC (µg/mL) of tested antibiotics for bacteria isolated from patients with cystic fibrosis enrolled in the study.

Isolate #	Tested antibiotics
	AK	MEM	ATM	CAZ	LEV	CN	DO	FEP
PA1	≥500	≥500	≥500	≥500	0.015625	–	–	–
PA2	≥500	≥500	≥500	≥500	≥500	–	–	–
PA3	≥500	≥500	≥500	≥500	0.00195	–	–	–
PA4	≥500	≥500	≥500	≥500	0.015625	–	–	–
PA5	≥500	≥500	≥500	≥500	≥500	–	–	–
PA6	≥500	≥500	≥500	≥500	≥500	–	–	–
PA7	≥500	≥500	≥500	≥500	≥500	–	–	–
PA8	≥500	≥500	≥500	≥500	0.03125	–	–	–
PA9	≥500	0.3125	≥500	≥500	0.0009765	–	–	–
PA10	≥500	≥500	≥500	≥500	0.00195	–	–	–
PA11	≥500	≥500	≥500	≥500	0.0625	–	–	–
PA12	0.3125	≥500	≥500	≥500	≥500	–	–	–
PA13	0.039	≥500	≥500	0.0009765	0.0009765	–	–	–
PA14	≥500	≥500	≥500	≥500	0.0078	–	–	–
PA15	0.0625	≥500	≥500	≥500	0.0625	–	–	–
PA16	≥500	≥500	≥500	≥500	≥500	–	–	–
PA17	≥500	≥500	≥500	≥500	0.0156	–	–	–
PP1	0.00781	≥500	≥500	≥500	≥500	–	–	–
PM1	0.03125	≥500	≥500	≥500	≥500	–	–	–
PF1	≥500	≥500	≥500	≥500	0.0009765	–	–	–
EC1	≥500	≥500	≥500	≥500	≥500	–	–	–
EC2	≥500	≥500	≥500	≥500	0.00195	–	–	–
SM1	≥500	≥500	≥500	0.0009765	0.00195	–	–	–
SM2	≥500	≥500	≥500	≥500	≥500	–	–	–
SA1	–	–	–	–	–	0.0009765	≥500	–
SA2	–	–	–	–	–	0.0009765	≥500	–
SA3	–	–	–	–	–	0.03125	≥500	–
SA4	–	–	–	–	–	0.0009765	≥500	–
SA5	–	–	–	–	–	0.03125	0.003906	–
SA6	–	–	–	–	–	≥500	≥500	–
SA7	–	–	–	–	–	0.0625	≥500	–
SA8	–	–	–	–	–	0.003906	≥500	–
SA9	–	–	–	–	–	0.015625	0.0009765	–
SA10	–	–	–	–	–	0.125	≥500	–
SA11	–	–	–	–	–	0.03125	≥500	–
SA12	–	–	–	–	–	0.00195	≥500	–
SA13	–	–	–	–	–	0.015625	≥500	–
SA14	–	–	–	–	–	≥500	≥500	–
SA15						0.00195	≥500
SA16						0.0625	≥500
SA17						0.000975	≥500
SA18						0.000975	≥500
SG		0.00391			0.015625			0.0009765

Abbreviations. PA: P. aeruginosa; PP: P. pseudoalcaligenes; PM: P. mendocina; PF: P. fluorescens; EC: E. coli; SM: S. marcescens; SA: S. aureus; SG: S. agalactiae; AK: amikacin; MEM: meropenem; ATM: aztreonam; CAZ: ceftazidime; LEV: levofloxacin; CN: gentamicin; DO: doxycycline; FEP: Cefepime; -: not tested.

Table 5. Frequency (percentage and number) of antibiotic resistance genes among Gram-negative and Gram-positive bacteria isolated from patients with cystic fibrosis enrolled in the study.

Bacterial isolates	Resistance gene in Gram-negative bacteria						Resistance gene in Gram-positive bacteria
	Frequency of carbapenem resistance genes, n (%)			Frequency of ESBL resistance genes, n (%)			Frequency of methicillin resistance genes, n (%)			Frequency of erythromycin and clindamycin resistance genes, n (%)
	BlaKPC	blaNDM	BlaVIM	BlaTEM	Bla CTX	Bla SHV	nuc	mecA	MRS (A/B)	ermA	ermB	ermC	ermTR	mefA	mefE	linB
P. aeruginosa	11 (65)	7 (41)	4 (24)	0 (0)	3 (18)	5 (29)	–	–	–	–	–	–	–	–	–	–
P. pseudoalcaligenes	1 (100)	1 (100)	1 (100)	0 (0)	0 (0)	0 (0)	–	–	–	–	–	–	–	–	–	–
S. marcescens	2 (100)	1 (50)	2 (100)	0 (0)	0 (0)	0 (0)	–	–	–	–	–	–	–	–	–	–
E. coli	2 (100)	2 (100)	0 (0)	0 (0)	2 (100)	0 (0)	–	–	–	–	–	–	–	–	–	–
P. fluorescens	0 (0)	0 (0)	0 (0)	0 (0)	0 (0)	0 (0)	–	–	–	–	–	–	–	–	–	–
P. mendocina	100 (1)	0 (0)	0 (0)	0 (0)	0 (0)	0 (0)	–	–	–	–	–	–	–	–	–	–
S. aureus	–	–	–	–	–	–	17 (94)	11 (61)	2 (11)	4 (22)	2 (11)	8 (44)	–	–	–	–
S. agalactiea	–	–	–	–	–	–	–	–	–	–	0 (0)		0 (0)	0 (0)	0 (0)	0 (0)
Number of isolates (%)	17 (71)	11 (46)	7 (29)	0 (0)	5 (21)	5 (21)	17 (89.5)	11 (63.2)	2 (15.8)	4 (21.1)	2 (15.8)	8 (42.1)	0 (0)	0 (0)	0 (0)	0 (0)

Table 1. Interpretation of optical density data for detection of biofilm formation [15].

Average OD value	Interpretation
OD ≤ ODc	No biofilm formation
ODc < OD ≤ 2 × ODc	Weak biofilm formation
2 × ODc < OD ≤ 4 × ODc	Moderate biofilm formation
4 × ODc < OD	Strong biofilm formation

OD: optical density at 575 nm. Optical density cut-off value (ODc) = average OD of negative control + 3 × standard deviation (SD) of the negative controls.

Siddhiqui S, Afreen U, Kotgire S. Evaluation of biofilm formation by three different methods and its antibiogram with special reference to indwelling medical devices from a tertiary care hospital. Ann Pathol Lab Med. 2018;5(2):171–176.

 Google Scholar

Data availability statement

All data generated or analyzed during this study are included in this article.

Table 1. Interpretation of optical density data for detection of biofilm formation [15].

Average OD value	Interpretation
OD ≤ ODc	No biofilm formation
ODc < OD ≤ 2 × ODc	Weak biofilm formation
2 × ODc < OD ≤ 4 × ODc	Moderate biofilm formation
4 × ODc < OD	Strong biofilm formation

OD: optical density at 575 nm. Optical density cut-off value (ODc) = average OD of negative control + 3 × standard deviation (SD) of the negative controls.