Antimicrobial Resistance and Molecular Characteristics of Methicillin-resistant Staphylococcus aureus Isolates from Children Patients in Iran

Figures & data

Table 1 Classification of Biofilm Formation Abilities by Microtiter Plate Method

Cut-Off Value Calculation	Mean of OD Values Results	Biofilm Formation Abilities
OD > 4×ODc	OD > 0.2	Strong
2×ODc < OD ≤4×ODc	0.1 < OD ≤ 0.2	Moderate
ODc < OD ≤ 2×ODc	0.05 < OD ≤ 0.1	Weak
OD ≤ 0.05	OD ≤ 0.05	None

Table 2 Oligonucleotide Primers Used in This Study

Genes	Primers Sequence (5´–3´)	Product Size (bp)	Reference
nuc	F-GCGATTGATGGTGATACGGTT R-AGCCAAGCCTTGACGAACTAAAGC	270	^Citation29
mecA	F-GTAGAAATGACTGAACGTCCGATAA R-CCAATTCCACATTGTTTCGCTCTAA	310	^Citation30
icaA	F-GGAGGTCTTTGGAAGCAAC R-TGCGACAAGAACTACTGCTG	390	In this study
icaD	F-GGAGGTCTTTGGAAGCAAC R-TGCGACAAGAACTACTGCTG	229	In this study
clfA	F-ATTGGCGTGGCTTCAGTGCT R-CGTTTCTTCCGTAGTTGCATTTG	280	In this study
clfB	F-GCAGCATTTACTACCGGTTC R-CTACAACAGAGCCAGCTTCA	301	In this study
fnbA	F-CACTGCGCCAGTTACAATAC R-GATGGTGGAGGTGGATATGT	306	In this study
fnbB	F-TCTCTGCAACTGCTGTAACG R-GGAAAGTGGGAGTTCAGCTA	320	In this study
cna	F-CGATTAAAGTGGCATGGCCG R-CTGGCAGCATATCTCCCGTT	333	In this study
eno	F-ACGTGCAGCAGCTGACT R-CAACAGCATCTTCAGTACCTTC	301	^Citation31
pvl	F-CTCTAGCCGATGTCGCTCAA R-ATACCTGAGGCTCGCCACTG	433	^Citation32
SCCmec I	F: GCTTTAAAGAGTGTCGTTACAGG R: GTTCTCTCATAGTATGACGTCC	613	^Citation33
SCCmec II	F: CGTTGAAGATGATGAAGCG R: CGAAATCAATGGTTAATGGACC	398	^Citation33
SCCmec III	F: CCATATTGTGTACGATGCG R: CCTTAGTTGTCGTAACAGATCG	280	^Citation33
SCCmec IVa	F: GCCTTATTCGAAGAAACCG R: CTACTCTTCTGAAAAGCGTCG	776	^Citation33
SCCmec IVb	F: TCTGGAATTACTTCAGCTGC R: AAACAATATTGCTCTCCCTC	493	^Citation33
SCCmec IVc	F: ACAATATTTGTATTATCGGAGAGC R: TTGGTATGAGGTATTGCTGG	200	^Citation33
SCCmec IVd	F: CTCAAAATACGGACCCCAATACA R: TGCTCCAGTAATTGCTAAAG	881	^Citation33
SCCmec V	F: GAACATTGTTACTTAAATGAGCG R: TGAAAGTTGTACCCTTGACACC	325	^Citation33

Table 3 The MIC Range of Vancomycin in MRSA Isolates

MIC (μg/mL)	n (%)
0.19	1 (1%)
0.25	8 (8%)
0.38	2 (2%)
0.5	28 (29%)
0.75	15 (15%)
1	23 (23.5%)
1.5	18 (18.5%)
2	2 (2%)
2.5	1 (1%)
Total	98 (100%)

Table 4 Percentage of Biofilm Formation in Microtiter Plate Method

Biofilm Formation	Number	Percent
Strong	1	1%
Moderate	8	8%
Weak	53	54%
None	36	37%
Total	98	100%

Table 5 Relationship Between Biofilm Formation and Antibiotic Resistance

Antibiotic	Resistance		Susceptible		Total	P-Value
	Biofilm +	Biofilm −	Biofilm +	Biofilm −
Erythromycin	44 (72%)	17 (28%)	18 (49%)	19 (51%)	98 (100%)	0.01
Clindamycin	40 (71%)	16 (29%)	22 (52%)	20 (48%)	98 (100%)	0.04
Gentamicin	18 (75%)	6 (25%)	44 (59%)	30 (41%)	98 (100%)	0.1
Rifampicin	8 (67%)	4 (33%)	54 (63%)	32 (37%)	98 (100%)	0.7
Minocycline	6 (60%)	4 (40%)	56 (65%)	32 (35%)	98 (100%)	0.8
Trimethoprim sulfamethoxazole	15 (63%)		46 (64%)	27 (36%)	98 (100%)	0.9
Linezolid	–	–	62 (63%)	36 (37%)	98 (100%)	–
Vancomycin	–	–	62 (63%)	36 (37%)	98 (100%)	–
Penicillin	62 (63%)	36 (37%)	–	–	98 (100%)	–
Cefoxitin	62 (63%)	36 (37%)	–	–	98 (100%)	–

Table 6 Multiplex PCR Results of SCCmec Typing

Genes	n (%)
SCCmec I	1 (1%)
SCCmec II	0
SCCmec III	18 (18%)
SCCmec IVa	73 (75%)
SCCmec IVb	4 (4%)
SCCmec IVc	2 (2%)
SCCmec IVd	0
SCCmec V	0

Figure 1 Antimicrobial resistance patterns of MRSA isolates.

Figure 2 Dendrogram of MRSA patterns generated by an UPGMA clustering method.

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