Isolation and antimicrobial susceptibility pattern of Staphylococcus aureus in patients with surgical site infection at Debre Markos Referral Hospital, Amhara Region, Ethiopia

Table 3 Bivariate and multivariable analysis of characteristics related with S. aureus isolation at Debre Markos Referral Hospital, Amhara, Ethiopia [December, 2011 - March, 2012]

Variables	Total	S. aureus positive	S. aureus negative	COR (95% CI)	p-value	AOR (95% CI)	p-value
Age
18-30	100	37	63	1
31-40	43	19	24	0.74 (0.35-1.53)	0.420
41-50	18	7	11	0.92 (0.32-2.58)	0.879
≥51	23	10	13	0.76 (0.30-1.91)	0.565
Sex
Female	123	52	71	1
Male	61	21	40	1.39 (0.73-2.64)	0.306
Pus consistency
Yellowish	126	58	68	1
Bloody	49	15	34	1.93 (0.95-3.89)	0.065
Duration of operation
≤30 minute	92	46	46	1		1
31-60 minute	29	11	18	1.63 (0.69-3.84)	0.258	1.40 (0.41-4.14)	0.29
≥61 minute	63	16	47	2.93 (1.46-5.91)	0.003	0.34 (0.73-2.13)	0.49
Type of surgery
Caesarean section	86	44	42	1		1
Laparotomy	57	12	45	3.92 (1.82-8.43)	0.0001	2.03 (1.91-7.01)	0.03
Appendectomy	12	5	7	1.46 (0.43-4.98)	0.539	0.78 (0.08-7.65)	0.83
Hysterectomy	9	4	5	1.31 (0.32-5.21)	0.702	0.56 (0.05-5.74)	0.62
Prostectomy	4	2	2	1.04 (0.14-7.78)	0.964	0.01 (0.91-8.01)	0.99
Salphangectomy	3	1	2	2.09 (0.18-3.97)	0.552	1.40 (0.06-17.98)	0.95
Others	13	5	8	1.67 (0.50-5.53)	0.397	0.03 (0.11-11.30)	0.99
Induration
No	69	21	48	1		1
Yes	115	52	63	0.53 (0.28-0.99)	0.049	0.60 (0.31-1.17)	0.14
Ward
Surgical	67	21	46	1
Gynaecology	117	52	65	0.57 (0.30-1.07)	0.082
Hospital stay
≤5 days	114	49	65	1
6-10 days	55	18	37	1.55 (0.78-3.04)	0.203
11-15 days	5	1	4	3.01 (0.32-27.83)	0.330
≥16 days	10	5	5	0.75 (0.20-2.74)	0.669

1= reference category induration- a focus or region of abnormally hardened tissue.

ISSN: 2049-3258