isepamicin and Osteomyelitis

We have developed a new drug delivery system using porous apatite-wollastonite glass ceramic (A-W GC) to treat osteomyelitis. A-W GC (porosity, 70% and 20% to 30%), or porous hydroxyapatite (HA) blocks (porosity 35% to 48%) used as controls, were soaked in mixtures of two antibiotics, isepamicin sulphate (ISP) and cefmetazole (CMZ) under high vacuum. We evaluated the release concentrations of the antibiotics from the blocks. The bactericidal concentration of ISP from A-W GC was maintained for more than 42 days, but that from HA decreased to below the detection limit after 28 days. The concentrations of CMZ from both materials were lower than those of ISP. An in vivo study using rabbit femora showed that an osseous concentration of ISP was maintained at eight weeks after implantation. Osteoconduction of the A-W GC block was good. Four patients with infected hip arthroplasties and one with osteomyelitis of the tibia have been treated with the new delivery system with excellent results.

Topics: Adult; Animals; Anti-Bacterial Agents; Apatites; Arthroplasty, Replacement, Hip; Calcium Compounds; Cefmetazole; Cephamycins; Ceramics; Drug Delivery Systems; Drug Implants; Drug Therapy, Combination; Durapatite; Female; Femur; Gentamicins; Glass; Hip Prosthesis; Humans; Male; Middle Aged; Osteomyelitis; Pilot Projects; Porosity; Prosthesis-Related Infections; Rabbits; Silicates; Tibia; Time Factors

Hydroxyapatite blocks (HAB) can be used to administer antibiotics or anticancer drugs because its porous structure allows the gradual administration of the pharmacologic agents. A novel drug delivery system using hydroxyapatite blocks was developed for osteomyelitis and postoperative infections occurring after joint replacement. To load the antibiotics, hydroxyapatite blocks were mixed with an antibiotic solution and centrifuged at 1500 rpm for 15 minutes or decompressed in vacuum container at 5 to 10 in. Hg for 20 minutes. Fifteen patients with osteomyelitis including one with tuberculosis and four with infections subsequent to joint replacement were treated with antibiotic-loaded hydroxyapatite blocks in combination with intravenous injection. Except in one case, all of the foci had completely healed at follow-up (range: 13 to 71 months; average: 39.7 months). These new methods are simple and can safely treat osteomyelitis in a one-stage operation.

Topics: Aged; Aged, 80 and over; Anti-Bacterial Agents; Biocompatible Materials; Combined Modality Therapy; Curettage; Drug Implants; Durapatite; Female; Follow-Up Studies; Gentamicins; Humans; Infusions, Intravenous; Joint Prosthesis; Male; Osteomyelitis; Porosity; Prosthesis-Related Infections; Radiography; Treatment Outcome