[Spontaneous infectious spondylodiscitis in adults. Analysis of 30 cases]

We revised retrospectively 30 cases of Spontaneous Infectious Spondylodiskitis (SIS) in adults, diagnosed between 1986 and 1997. The mean age of the patients was 68.8 years; 56.7% were males. The identifiable causes were infectious endocarditis 13 (43.3%); tuberculosis 7 (23.3%); urinary tract infection 4 (13.3%); bacteremia with focus 2 (6.7%) and without focus 2 (6.7%). The cause was not identified in other 2 cases (6.7%). Infections were due to pyogenic bacteriae in 19 (63.3%); tuberculosis 6 (20%) and unknown 5 (16.7%). All patients had localized pain, 70% fever, 36.7% irradiated pain and 23.3% paraparesis. Fever was more frequent in patients with pyogenic etiology than in those with tuberculous SIS (p = 0.004). Blood cultures were positive in 70.4%. Percutaneous aspiration of the disc was performed in 13 patients; cultures were positive in 7. Causal germs were Streptococcus spp. 33.3%; Mycobacterium tuberculosis 20%; Staphylococcus spp. 16.6%; Escherichia coli 6.6%; Pseudomonas aeruginosa 6.6%. There was no bacteriological recovery in 5 (16.7%). Localization was lumbar in 18 (60%), dorsal in 8 (26.6%) and cervical in 4 (13.3%). X-ray of the spine was positive in 63.3% of the cases. Technetium scan in 90.5%, CT in 85.7% and MRI in 100% of cases in which it was carried out. All patients received antibiotic treatment with a median duration of 6 weeks for pyogenic SIS and one year for tuberculous SIS. Eighty three percent required immobilizing brace and 10% surgery for stabilization. Thirty six percent of patients presented complications, most of them related to the causal disease. There was a statistically significant association between mortality and diabetes.