Efficacy of ciprofloxacin implants in treating experimental osteomyelitis

Abstract

Ciprofloxacin (CFX) implants containing poly(D,L-lactide) and calcium phosphates (tricalcium phosphate and hydroxyapatite) was evaluated in 50 rabbits in an experimental osteomyelitis model. Their femoral cavity was inoculated with Staphylococcus aureus. After 2 weeks, the infected focus was cleaned out and the delivery system implanted. The infection and subsequent response to treatment were evaluated by microbiological analysis, biochemical and hematological markers, body weight, temperature, clinical signs, X-rays, and histology. Infected bone cultures, treated with CFX implants, showed reduced bacterial growth against controls. All CFX was released within 6 weeks. All animals recovered within 4 weeks. Even 12 weeks after implantation, no recurrence of infection was observed. Serum C-reactive protein, platelet, and leukocyte levels increased in all animals before treatment, and 4 weeks after it were maintained or rose in control animals, while decreased to normal levels in treated ones. Body weight was characterized by pretreatment losses, then gains during recuperation, or further loss in untreated animals; with no significant intraindividual differences in body temperature. Body weight, leucocytes, platelets, and C-reactive protein turned out to be highly useful markers for monitoring this kind of infection and its treatment. CFX implants demonstrated to be an effective therapy for S. aureus bone infection. Their efficacy was also reflected in decreasing severity of clinical signs, nonprogress of radiological signs indicative of infection, and good integration into bone structure. Histological examination revealed repair, with new bone formation extending into implants.

Biomaterials approaches to treating implant-associated osteomyelitis

“…After inoculating the bacteria into a localized site within the bone (usually into the marrow cavity), bacteria spread throughout the length of the medullary cavity, invade cracks and canaliculi within the bone, and can also infect the surrounding soft tissue. The joint capsule is also vulnerable to infection in the studies where the inoculation took place through the tibial plateau or femoral intercondylar notch [3, 4, 44]. Consequently, the most reliable processing method is to completely grind and homogenize the whole bone, marrow, and surrounding soft tissue before inoculating serial dilutions of the suspensions onto media agar plates for CFU counts.…”

Anti-sessile bacterial and cytocompatibility properties of CHX-loaded nanohydroxyapatite

“…There is a broad choice of active molecules such as anticoagulants, antiinflammatory drugs, antibiotics and extracellular matrix proteins [2]. Several authors [4][5][6][7][8] reported that the adsorption of antibiotics (e.g., gentamicin, ciprofloxacin, amoxicillin, and erythromycin) on medical devices has a huge potential in the medical field. How-ever, there is a consensus in the medical area on the rational use of antibiotics in order to avoid microbial resistance.…”

Natural rubber latex used as drug delivery system in guided bone regeneration (GBR)

“…BMPs have strong bone-inductive activity and many works have been dedicated to the development of delivery systems that sustain their gradual release for dental and orthopedic uses [14][15][16][17] . One key issue in this particular problem is that bone regeneration is a long term processes, typically in humans of the order of 8-16 weeks [18][19][20][21] . Thus the ideal membrane would have to release BMPs along many weeks.…”