Antibiotic-loaded bone void filler accelerates healing in a femoral condylar rat model.

AIMS: Demineralised bone matrix (DBM) is rarely used for the local delivery of prophylactic antibiotics. Our aim, in this study, was to show that a graft with a bioactive glass and DBM combination, which is currently available for clinical use, can be loaded with tobramycin and release levels of antibiotic greater than the minimum inhibitory concentration for Staphylococcus aureus without interfering with the bone healing properties of the graft, thus protecting the graft and surrounding tissues from infection. MATERIALS AND METHODS: Antibiotic was loaded into a graft and subsequently evaluated for drug elution kinetics and the inhibition of bacterial growth. A rat femoral condylar plug model was used to determine the effect of the graft, loaded with antibiotic, on bone healing. RESULTS: We found that tobramycin loaded into a graft composed of bioglass and DBM eluted antibiotic above the minimum inhibitory concentration for three days in vitro. It was also found that the antibiotic loaded into the graft produced no adverse effects on the bone healing properties of the DBM at a lower level of antibiotic. CONCLUSION: This antibiotic-loaded bone void filler may represent a promising option for the delivery of local antibiotics in orthopaedic surgery. Cite this article: Bone Joint J 2016;98-B:1126-31.

Fatal respiratory disease due to Corynebacterium diphtheriae: case report and review of guidelines for management, investigation, and control.

Dramatic reductions in the incidence of diphtheria and high levels of childhood vaccination in recent decades have led the United States to establish the goal of diphtheria elimination among persons < or = 25 years of age by the year 2000. In 1990, an unimmunized 25-month-old child died of respiratory diphtheria in Dade County, Florida, before treatment with diphtheria antitoxin could be instituted. Twenty-three asymptomatic household contacts and other close contacts of the child were identified, cultured for Corynebacterium diphtheriae, given antimicrobial prophylaxis, and vaccinated with diphtheria toxoid when indicated. Three contacts (13%) had pharyngeal cultures positive for toxigenic C. diphtheriae of the same type as that causing infection in the deceased child, but no additional cases developed. Although the source of infection was not determined, three other close contacts had recently been to Haiti, where diphtheria is endemic. A serological survey of 396 children < 5 years of age who received care at a medical center in Dade County revealed that 22% lacked protective immunity to diphtheria. Attainment of the goal of diphtheria elimination among persons < or = 25 years of age--and ultimately among all persons--will depend on the maintenance of a high level of clinical awareness of the disease, the prompt institution of preventive measures among close contacts of patients with sporadic cases, and improved vaccination levels among infants, children, and adults.

Measles outbreak among unvaccinated preschool-aged children: opportunities missed by health care providers to administer measles vaccine.

A measles outbreak in an inner-city area primarily involved preschool-aged children younger than 5 years of age. The reasons why 31 unvaccinated preschool children with measles disease had not been vaccinated were investigated. For some patients, health care providers missed opportunities to vaccinate eligible patients against measles. Of the 26 patients whose full immunization status was known, ten (38%) were vaccinated with diphtheria and tetanus toxoids and pertussis vaccine and/or oral poliovirus vaccine at a time when they could have received measles vaccine simultaneously, according to recommendations of the Immunization Practices Advisory Committee and the American Academy of Pediatrics. In addition, five of ten health care providers interviewed missed at least one opportunity to administer measles vaccine because of a minor illness that was not a contraindication to vaccination. Unvaccinated patients were more likely to receive health care in the public sector, have single mothers, and have parents who had no knowledge of existing vaccines; they were less likely to be age-appropriately immunized with other antigens. If measles immunization levels among preschool children in the United States are to be increased, education of both health care providers and parents, coupled with innovative strategies targeted to preschool children, particularly of low socioeconomic groups in inner cities, are needed.