Table 2

Results of analyses of specimens from 20 patients with suspected spondylitis or epidural abscess: broad range bacterial PCR, DNA sequencing, bacterial culture, data on operative technique, preoperative antimicrobial treatment, and blood cultures, and final diagnosis

No	Initial diagnosis	Operative technique	Spinal specimen	Bacterial culture result	PCR	Sequencing result	Homology (%)^a	Sequence length (nt)^a	Preoperative antibiotics^b	Blood culture result^c	Final diagnosis
^aThe per cent homology and the length of the overlapping sequence for the best match.
^bAn effective antimicrobial treatment against the recognised microbe in the specimen; duration of preoperative antibiotic treatment is given in parentheses.
^cThe number of days a positive blood culture result was obtained before the specimen for the PCR assay and culture was taken are given in parentheses. Unless otherwise indicated, blood culture was taken on the same day as the PCR.
^dThe sample was interpreted to contain several species if the electropherogram showed strong signals but multiple overlapping peaks in some locations.
^eNegative result.
^fThe patient received ofloxacin.
^gThe patient received ceftriaxone and metronidazole.
^hThe patient received trimethoprim prophylaxis for urinary tract infection.
ⁱAseptic spondylitis was diagnosed as one component of an autoimmune disorder of unknown origin, as described in ref29.
^jSequencing failure was assumed if the sequencing signals reported by the instrument were weak.
nt, nucleotides; PCR, polymerase chain reaction.
1	Spondylitis	Open biopsy	Pus	Staph aureus	+	Staphylococcus sp, probably several species^d	86.3	164	Yes (8 days)	Staph aureus (−8 days)	Spondylitis and epidural abscess
2	Epidural abscess	Open biopsy	Pus	−^e	+	Staphylococcus sp	94.7	216	Yes (15 days)	Staph aureus (−15 days)	Epidural abscess
3	Spondylitis	Open biopsy	Bone and disc	−	+	Staph aureus	98.6	441	Yes (12 days)	Staph aureus (−14 days)	Spondylitis
4	Postoperative spondylodiscitis	Open biopsy	Pus	−	+	Str intermedius	98.1	423	Yes (13 days)	Not done	Postoperative spondylodiscitis
5	Vertebral tumour	Open biopsy	Bone	−	+	Str mitis/gordonii/ oralis/peroris	100	418	Yes (4 days)	Not done	Spondylitis
6	Spondylitis	Puncture	Pus	−	+	Pseudomonas sp	97.4	268	Yes (2 days)	Str mitis (−3 days)	Spondylitis and infective endocarditis
7	Spondylitis	Stereotactic biopsy	Bone	Staph aureus	−				No	Staph aureus	Spondylitis
8	Postoperative epidural abscess	Open biopsy	Pus	Pseudomonas aeruginosa	−				No	Pseudomonas aeruginosa	Postoperative spondylodiscitis and epidural abscess
9	Vertebral tumour	Open biopsy	Bone	−	−				Yes^f (4 days)	−	Spondylitis
10	Spondylitis and epidural abscess	Open biopsy	Bone	−	−				No	−	Spondylitis
11	Epidural abscess	Open biopsy	Bone	−	−				Yes^g (10 days)	Not done	Spondylitis
12	Postoperative spondylodiscitis and epidural abscess	Open biopsy	Disc	−	−				No	−	Postoperative spondylodiscitis
13	Spondylitis	Open biopsy	Bone	−	−				Yes^h	−	Aseptic spondylitisⁱ
14	Spondylitis	Open biopsy	Bone	−	−				No	Not done	Aseptic spondylitis
15	Spondylitis	Open biopsy	Bone	−	−				No	−	Aseptic spondylitis
16	Spondylitis	Open biopsy	Bone	−	−				Yes (one dose)	−	Lymphoma
17	Spondylitis	Open biopsy	Bone	−	−				Yes (8 days)	−	Lymphoma
18	Vertebral tumour or infection	Open biopsy	Bone	−	+	Failure^j			Yes (one dose)	Not done	Lymphoma
19	Vertebral tumour or infection	Open biopsy	Epidural tumour	−	−				Yes (one dose)	Not done	Lymphoma
20	Vertebral tumour or infection	Open biopsy	Epidural tumour	−	−				Yes (one dose)	Not done	Plasma cell granuloma