Antibiotic therapy of osteomyelitis in outpatients

The treatment of infected tibial pilon fractures

A total of 33 patients with infection after pilon fracture were retrospectively reviewed from 1988 to 1992. Twenty patients were transfered from peripheral hospitals with active osteitis, 13 patients were treated primarily in our hospital. Factors inducing infection in this group of patients are discussed critically. All patients underwent radical debridement. Restoration of bone stability was required in 72%. Due to the extent of infection, segmental resection had to be perfomed on 7 patients. Resulting soft tissue defects were closed with free flaps in 11 cases. Infection was controlled in 31 patients (93%), but only 8 could be classified as "cured" (24%). Two patients had amputations after failure of treatment. Despite successful therapy, the functional results are poor. Therefore, avoiding infection, has top priority in the post fracture treatment. The correct form of osteosynthesis adapted to the soft tissue lesion can lower infection rates significantly. Soft tissue defects, resulting from open fractures or after primary treatment, have to be closed by flap transfer within a short period of time. The management of the soft tissue is at least as important as the reconstruction of the bone in the treatment of pilon fractures.

Outpatient parenteral antibiotic therapy

Clinical studies have shown that outpatient administration of parenteral antibiotics is sage, cost-effective and practical. The development of new antibiotics with prolonged half-lives, such as ceftriaxone or cefotetan, has facilitated outpatient parenteral antibiotic therapy (OPAT). Good OPAT management requires coordination of physicians, nurses, pharmacists and health care administrators, and the establishment of firm guidelines. A variety of infections can be treated through OPAT, including osteomyelitis and soft tissue infections, chronic urinary tract infections, and ear, nose and throat infections.

Antimicrobial treatment of chronic osteomyelitis

Chronic osteomyelitis has been a difficult problem for patients and the treating physicians. Appropriate antibiotic therapy is necessary to arrest osteomyelitis along with adequate surgical therapy. Factors involved in choosing the appropriate antibiotic(s) include infection type, infecting organism, sensitivity results, host factors, and antibiotic characteristics. Initially, antibiotics are chosen on the basis of the organisms that are suspected to be causing the infection. Once the infecting organism(s) is isolated and sensitivities are established, the initial antibiotic(s) may be modified. In selecting specific antibiotics for the treatment of osteomyelitis, the type of infection, current hospital sensitivity resistance patterns, and the risk of adverse reactions must be strongly appraised. Antibiotic classes used in the treatment of osteomyelitis include penicillins, beta-lactamase inhibitors, cephalosporins, other beta-lactams (aztreonam and imipenem), vancomycin, clindamycin, rifampin, aminoglycosides, fluoroquinolones, trimethoprim-sulfamethoxazole, metronidazole, and new investigational agents including teicoplanin, quinupristin/dalfopristin, and oxazolidinones. Traditional treatments have used operative procedures followed by 4 to 6 weeks of parenteral antibiotics. Adjunctive therapy for treating chronic osteomyelitis may be achieved by using beads, spacers, or coated implants to deliver local antibiotic therapy and/or by using hyperbaric oxygen therapy (once per day for 90-120 minutes at two to three atmospheres at 100% oxygen).

Evolution of outpatient parenteral antibiotic therapy

The future will no doubt continue to promote safe, cost-effective therapies such as outpatient intravenous therapy. It is imperative that physicians trained and knowledgeable in the administration of outpatient intravenous antimicrobial drug administration continue to assume responsibility and leadership roles.

Outpatient parenteral antibiotic therapy. Management of serious infections. Part II: Amenable infections and models for delivery. Infusion center, office, and home

Outpatient parenteral antibiotic therapy (OPAT) administered in an infusion center often offers the advantages but not the expense of the hospital setting. Office-based OPAT maintains the physician-patient relationship but may be impractical for the physician. Home administration is ideal for selected patients, but when it is provided by an infusion company, the physician may be sidestepped.

Ceftriaxone in treatment of serious infections. Osteomyelitis

Ceftriaxone is an effective and safe agent for the treatment of osteomyelitis. It is active against most of the causative organisms. Combined with surgery, it is useful for all types of osteomyelitis. In addition, its once-daily dosing has made outpatient therapy feasible for most patients. Questions that remain are whether full treatment with 2 gm every 24 hours for four to six weeks is needed for osteomyelitis or whether 1 gm/day would provide comparable results. The relevance of minimal inhibitory/bactericidal concentrations and serum inhibitory/bactericidal concentrations has not been-determined. Some questions remain about the cure rate of ceftriaxone against S. aureus osteomyelitis, although most cases do well. Comparative studies with agents such as cefazolin or oxacillin would be helpful to resolve this issue. Long-term follow-up of patients treated for osteomyelitis outcome has not been done in sufficient detail to be certain of the comparative results of different antimicrobials. The success rate of the quinolones against gram-negative osteomyelitis appears good, but their activity against gram-positive organisms is uncertain, and development of resistance is a problem. Questions still linger in regard to how much can be accomplished with antimicrobial therapy without surgery and how long antimicrobials are needed once effective surgery has been performed.

Antimicrobial therapy in special situations, including extended care facilities and the outpatient setting

After implementation of the diagnosis-related group (DRG) payment system by the federal government there has been a shift of medical care, including intravenous antibiotic therapy, from the acute care hospital to the extended care facility and to the patient's home. Antibiotic selection in the extended care facility involves consideration of a number of factors such as the health status of the patient and the common infections that occur in patients in these facilities, which generally are similar to hospital-acquired infections. Home intravenous therapy is appropriate for treatment of some infectious diseases and is generally safe, although a number of infections and other complications may occur and may require consideration by the physician and the home therapy nurse. Common infectious complications and choices of antibiotic therapy in these two settings are reviewed.