Antibiotic prophylaxis in surgery of the intervertebral disc: A comparison between gentamicin and cefuroxime

Abstract

Antibiotics are often administrated prophylactically in spinal procedures to reduce the risk of infection of the disc space. It is still not known which antibiotics are able to penetrate the intervertebral disc effectively. In a prospective, randomised, double-blind clinical study, we examined the penetration of the intervertebral discs of two commonly used antibiotics, cefuroxime and gentamicin. The patients, randomised into two groups, received either 1.5 g of cefuroxime or 5 mg/kg of gentamicin prophylactically two hours before their intervertebral discs were removed. A specimen of blood, from which serum antibiotic levels were determined, was obtained at the time of discectomy. Therapeutic levels of antibiotic were detectable in the intervertebral discs of the ten patients who received gentamicin. Only two of the ten patients (20%) who received cefuroxime had a quantifiable level of antibiotic in their discs although therapeutic serum levels of cefuroxime were found in all ten patients. Our results show that cefuroxime does not diffuse into human intervertebral discs as readily as gentamicin. It is possible that the charge due to ionisable groups on the antibiotics can influence the penetration of the antibiotics. We therefore recommend the use of gentamicin in a single prophylactic dose for all spinal procedures in order to reduce the risk of discitis.

Nutrition of the Intervertebral Disc

“…10 They showed that although short-term exercise (6 hours) had no effect on transport into the disc, 26 long-term exercise (3 months) significantly increased rates of sulfate and oxygen transport into the disc, possibly because of remodeling of the microcirculation at the vertebral body-disc interface. [31][32][33] Magnetic Resonance Imaging Studies In recent years, development in MRI has allowed almost noninvasive investigations of transport into the disc in animals and humans in vivo. 28 Animal studies also showed that the degree of solute penetration depended on the characteristics of the solute, with both solute size and charge affecting transport.…”

Kinetics of charged antibiotic penetration into human intervertebral discs: A numerical study

“…z is the valence of the antibiotics. Regions with concentration higher than the minimum inhibitory concentration (MIC) [e.g., 1 mg/L (Tai et al, 2002; Walters et al, 2006a)] were colored in Crimson.…”

“…After age 16, there are no blood vessels which go into the IVD. Penetration of antibiotics into IVD has been studied in animals (Currier et al, 1994; Eismont et al, 1987; Fraser et al, 1989; Riley et al, 1994; Scuderi et al, 1993; Thomas et al, 1995; Walters et al, 2006b) and humans (Gibson et al, 1987; Lang et al, 1994; Tai et al, 2002; Walters et al, 2006a). These studies have suggested that the ability of antibiotics to penetrate into IVDs depends on several factors, such as antibiotic molecular weight (size), antibiotic charge, IVD porosity, etc.…”

“…A number of experimental studies have indicated that electrical charge plays a significant role in penetration of antibiotics into discs (Conaughty et al, 2006; Gibson et al, 1987; Riley et al, 1994; Scuderi et al, 1993; Tai et al, 2002; Thomas et al, 1995). Gibson et al (1987) reported that despite high levels of flucloxacillin and cephadrine in serum, little antibiotic could be detected in AF or NP harvested 30 minutes to 4 hours after intravenous (IV) administration in the 12 adolescent patients (Gibson et al, 1987).…”

“…Gibson et al (1987) reported that despite high levels of flucloxacillin and cephadrine in serum, little antibiotic could be detected in AF or NP harvested 30 minutes to 4 hours after intravenous (IV) administration in the 12 adolescent patients (Gibson et al, 1987). Tai et al (2002) examined the penetration of negatively charged cefuroxime and positively charged gentamicin into patients and they found that gentamicin diffused into discs much easier than cefuroxime (Tai et al, 2002). In a rabbit model of IVD infection with methicillin-resistant Staph aureus, Conaughty et al (2006) found that intravenous treatment with positively charged vancomycin was much more effective than treatment with negatively charged linezolid in resolving the infection.…”