Ciprofloxacin in the Treatment of Chronic Osteomyelitis in Adults

Abstract

The use offluoroquinolones as a treatment modality in osteomyelitis is a consequence of their broad antibacterial spectrum, high degree of penetration into bone tissue and low incidence of adverse effects (Tice et al. 1988). Ciprofloxacin, which has high activity against Pseudomonas aeruginosa and other Gram-negative and Gram-positive bacteria (Canton et al. 1992; Desplaces & Acar 1988), should playa major role in the treatment of chronic post-traumatic osteomyelitis complicating open fractures. This study was designed to further test the efficacy and safety of intravenous ciprofloxacin followed by oral ciprofloxacin vs intravenous ceftriaxone plus amikacin in the treatment of chronic osteomyelitis. 70 adults with chronic post-traumatic osteomyelitis were enrolled in an open randomised comparative study. The patients were allocated to one of the 2 groups as follows: group A included 31 males and 4 females, mean age 32.7 years; and group B comprised 32 males and 3 females, mean age 35.7 years. Clinical diagnoses were confirmed by routine radiographs in all 70 patients. Bacteriological diagnoses were based upon analysis of material obtained by surgical excision or biopsy of the affected bony area in all 70 patients. Before treatment was begun, all patients from both groups underwent surgery, and 2 bone biopsy cultures were performed and repeated 3, 8, 15 and 21 days after the beginning of the treatment. The bone cultures were grown following standard microbiological procedures. All organisms isolated from bone tissue were identified, and their susceptibilities to ciprofloxacin, ceftriaxone and amikacin were determined using standard methods. The organisms isolated from group A and group B, respectively, included P. aeruginosa (7 and 6 strains), Escherichia coli (9 and II strains), Proteus mirabilis (3 and 5 strains), Klebsiella pneumoniae (7 and 5 strains), Enterobacter aerogenes (4 and 3 strains), and Staphylococcus aureus (5 and 6 strains). All organisms were sensitive to the 3 drugs. 35 patients from group A were treated with intravenous ciprofloxacin 200mg twice daily for 14 days, followed by oral administration of 500mg bid for 75 days. The 35 patients in group B received ceftriaxone plus amikacin intravenously (the ceftriaxone dose was 2 g/day and that of amikacin 500mg twice daily) for 90 days. Clinical and bacteriological assessment after a follow-up period averaging 12 months indicated cure in all patients from both groups. Adverse reactions occurred in 6 patients who were treated with ciprofloxacin and in 19 patients who received ceftriaxone plus amikacin; these are shown in table I. Our results show that the 2 antibiotic regimens were equally effective in the treatment ofpost-traumatic chronic osteomyelitis due to Gram-negative and Gram-positive bacteria. Ciprofloxacin administered orally is well tolerated and safe for prolonged administration. We conclude that surgical measures together with the intravenous administration of the antibiotics used in this study are of primary importance in the management of chronic osteomyelitis. The differences between the 2 groups with regard to the duration of intravenous therapy and the incidence of adverse effects were statistically significant.