Table 1. Clinical characteristics and treatment outcomes of patients with vertebral osteomyelitis caused by methicillin-susceptible Staphylococcus aureus.
| Characteristics | No. (%) | P-value | ||||
|---|---|---|---|---|---|---|
| Total (N = 100) | Treatment success (N = 84) | Treatment failure (N = 16) | ||||
| Demography | ||||||
| Age >65 years | 56 (56.0) | 43 (51.2) | 13 (81.3) | 0.026 | ||
| Male gender | 58 (58.0) | 48 (57.1) | 10 (62.5) | 0.691 | ||
| Obesity (BMI >25 kg/m2) | 26 (26.0) | 22 (26.2) | 4 (25.0) | 1.000 | ||
| Comorbid conditions at the time of diagnosis | ||||||
| Presence of one or more comorbid conditions | 53 (53.0) | 45 (53.6) | 8 (53.0) | 0.793 | ||
| Solid tumor | 4 (4.0) | 4 (4.8) | 0 | 1.000 | ||
| Diabetes mellitus | 32 (32.0) | 26 (32.0) | 6 (37.5) | 0.607 | ||
| Liver cirrhosis | 5 (5.0) | 4 (4.8) | 1 (6.3) | 1.000 | ||
| Alcoholism | 6 (6.0) | 6 (7.1) | 0 | 0.586 | ||
| Rheumatoid arthritis | 3 (3.0) | 2 (2.4) | 1 (6.3) | 0.411 | ||
| ESRD on renal replacement therapy | 3 (3.0) | 3 (3.6) | 0 | 1.000 | ||
| Immunosuppressive therapy within 30 days | 2 (2.0) | 2 (2.4) | 0 | 1.000 | ||
| History of spinal trauma or fracture within 6 months | 14 (14.0) | 13 (15.5) | 1 (6.3) | 0.458 | ||
| Prior VO at the same site | 2 (2.0) | 2 (2.4) | 0 | 1.000 | ||
| Clinical or laboratory findings at the time of diagnosis | ||||||
| Duration of symptoms before presentation (median [IQR], days) | 7 (3–19) | 7 (3–18) | 7 (2–21) | 0.819 | ||
| Back pain | 93 (93.0) | 78 (92.9) | 15 (93.8) | 1.000 | ||
| Fever or a history of fever | 53 (53.0) | 44 (52.4) | 9 (56.3) | 0.776 | ||
| Neurologic symptoms | 41 (41.0) | 36 (42.9) | 5 (31.3) | 0.387 | ||
| Leukocytosis (WBC >10,000 cells/mm3) | 66 (66.0) | 54 (64.3) | 12 (66.0) | 0.407 | ||
| Elevated CRP (>1 mg/dL) | 95 (95.0) | 80 (95.2) | 15 (93.8) | 1.000 | ||
| Elevated ESR (>20 mm/h) | 79 (79.0) | 66 (78.6) | 13 (81.3) | 1.000 | ||
| Azotemia (BUN >20 mg/dL or serum creatinine >1.5 mg/dL) | 40 (40.0) | 32 (38.1) | 8 (50.0) | 0.373 | ||
| Radiographic findings at the time of diagnosis | ||||||
| Involved spines | ||||||
| Cervical spine | 10 (10.0) | 10 (11.9) | 0 | 0.358 | ||
| Thoracic spine | 27 (27.0) | 21 (25.0) | 6 (37.5) | 0.359 | ||
| Lumbosacral spine | 76 (76.0) | 65 (77.4) | 11 (68.8) | 0.525 | ||
| Multifocal involvement | 13 (13.0) | 12 (14.3) | 1 (6.3) | 0.687 | ||
| Involvement of ≥3 vertebral segments | 34 (34.0) | 28 (33.3) | 6 (37.5) | 0.747 | ||
| Infectious complications around the spinal column | 93 (93.0) | 77 (91.7) | 16 (100.0) | 0.594 | ||
| Paravertebral extension | 52 (52.0) | 39 (46.4) | 13 (81.3) | 0.011 | ||
| Psoas abscess | 44 (44.0) | 36 (42.9) | 8 (50.0) | 0.598 | ||
| Epidural extension | 63 (63.0) | 55 (65.5) | 8 (50.0) | 0.240 | ||
| Meningeal involvement | 1 (1.0) | 1 (1.2) | 0 | 1.000 | ||
| Positive culture specimens | ||||||
| Blood | 71 (71.0) | 60 (71.4) | 11 (68.8) | 1.000 | ||
| Purulent discharge | 14 (14.0) | 13 (15.5) | 1 (6.3) | 0.458 | ||
| Aspiration or biopsy specimen | 11 (11.0) | 11 (13.1) | 0 | 0.204 | ||
| Surgical specimen | 46 (46.0) | 38 (45.2) | 8 (50.0) | 0.726 | ||
| Biopsy or surgical procedure after initial presentation | ||||||
| Biopsy | 33 (33.0) | 26 (31.0) | 7 (43.8) | 0.318 | ||
| Surgical procedure | 63 (63.0) | 54 (64.3) | 9 (56.3) | 0.542 | ||
| Multiple surgical procedures | 15 (15.0) | 12 (14.3) | 3 (18.8) | 0.704 | ||
| Implant insertion during surgical procedures | 24 (24.0) | 20 (23.8) | 4 (25.0) | 1.000 | ||
| Antibiotic therapy | ||||||
| Interval from presentation to appropriate antibiotic therapy (median [IQR], days) | 2 (0–6) | 3 (0–6) | 1 (0–6) | 0.499 | ||
| Duration of appropriate parenteral antibiotic therapy (median [IQR], days) | 36 (21–51) | 36 (21–52) | 32 (7–48) | 0.486 | ||
| Duration of appropriate oral antibiotic therapy (median [IQR], days) | 20 (0–45) | 28 (0–46) | 0 (0–32) | 0.074 | ||
| Duration of appropriate total antibiotic therapy (median [IQR], days) | 61 (33–97) | 61 (35–102) | 48 (7–91) | 0.165 | ||
| Clinical courses | ||||||
| Improvement of the follow-up CRP | 66 (66.0) | 60 (71.4) | 6 (37.5) | 0.009 | ||
| Improvement of the follow-up ESR | 45 (45.0) | 40 (47.6) | 5 (31.3) | 0.228 | ||
| Clinical outcomes | ||||||
| Length of hospital stay (median [IQR], days) | 45 (30–66) | 46 (34–66) | 37 (13–86) | 0.275 | ||
| Interval from discontinuation of antibiotic therapy to end of follow-up (median [IQR], days) | 152 (41–694) | 159 (46–693) | 65 (0–929) | 0.268 | ||
BMI, body mass index; ESRD, end-stage renal disease; VO, vertebral osteomyelitis; IQR, interquartile range; WBC, white blood cells; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; BUN, blood urea nitrogen.