TABLE 2.

Result of D-test obtained with MRSA and MSSA isolates showing presence of erythromycin resistance genes and its correlation with MLSB phenotypes among Staphylococcus aureus.

Erythromycin resistance and MSB phenotypes	Phenotype (%)	Gene combinations
		msrA	ermA	ermC	mphC	msrA, ermC	ermA, ermC	ermC, mphC	msrA, ermA, ermC	msrA, ermC, mphC	msrA, ermA, ermC, mphC
MRSA (n=32)
ER-S, CL-S	10 (31.25%)	0	0	0	0	3 (30%)	0	1 (10%)	1 (10%)	3 (30%)	1 (10%)
ER-R, CL-S (MSB phenotype)	2 (6.25%)	0	0	0	0	1 (50%)	0	0	0	1 (50%)	0
ER-R, CL-R (cMLSB phenotype)	6 (18.75%)	0	0	1 (16.6 %)	0	0	3 (50%)	1 (16.6%)	0	1 (16.6%)	0
ER-R, CL-D (iMLSB phenotype)	10 (31.25%)	0	0	6 (60%)	0	0	1 (10%)	0	1 (10%)	1 (10%)	0
MSSA (n=77)
ER-S, CL-S	52 (67.5%)	3 (5.7%)	1 (1.9%)	16 (30.7 %)	1 (1.9%)	20 (38.4%)	0	4 (7.6%)	0	4 (7.6%)	0
ER-R, CL-S (MSB phenotype)	12 (15.5%)	0	1 (8.3%)	1 (8.3%)	2 (16.6 %)	6 (50%)	0	0	0	0	0
ER-R, CL-R (cMLSB phenotype)	1 (1.29%)	0	0	0	0	0	0	0	1 (100%)	0	0
ER-R, CL-D (iMLSB phenotype)	4 (5.19%)	0	0	1 (25%)	0	3 (75%)	0	0	0	0	0

S: sensitive; R: resistance; ER: erythromycin; CL: clindamycin.