Analysis of predisposing factors for contamination of bone and tendon allografts.

Bone and tissue allografts are widely used in transplantation. The increasing demand for safe allografts must be met, while minimizing disease transmission. We analysed the incidence and potential risk factors of allograft contamination and the effectiveness of disinfection, by reviewing 22 years of tissue bank activity and 474 donor procurements. We also compared different disinfection procedures used over the 22 years. The overall contamination rate was 10.1%. Risk factors were related to the donor or procurement method. Immediate culture at the tissue recovery site diminished the rate of false positives by reducing later sample manipulation. High-virulence allograft contamination was mainly related to donor factors, while low-virulence contamination was related to procurement methods. Analysis of donor-related risk factors showed no statistical differences for age, sex, or cause of death. An intensive care unit stay was associated with less contamination with high-virulence microbes. Procurement in a setting other than an operating theatre was associated with higher contamination rate. Team experience reduced contamination. Pelvic and tendon allografts were most frequently contaminated. Proper disinfection considerably reduced the contamination rate to 3.6%. We conclude that procurement must be performed under aseptic conditions, with short delays, and by trained personnel. Grafts should be disinfected and packed as soon as possible.

Listeria infections associated with infliximab: case reports.

Infliximab is a human-murine chimeric monoclonal antibody directed against tumor necrosis factor alpha (TNFalpha). Infliximab and other TNF blockers are used to treat inflammatory diseases such as rheumatoid arthritis (RA). TNF blockers are suspected to play a key role in some infections. We report here two cases of Listeria monocytogenes sepsis associated with infliximab treatment for RA. The first patient developed a terminal ileitis and a bacteraemia after three doses of infliximab; the second RA patient presented a bacteraemia associated with a prosthetic joint arthritis of the left hip, both related to Listeria. Those two cases occurred in a population of 518 patients treated with TNF blockers in our hospitals since the year 2000. Those events are of particular interest because of the severity of the infection, because the treatment differs from other infections, and because that, in the rheumatology unit, septic arthritis can mimic RA symptoms. They enhance the likelihood for this drug to increase the risk for infections with germs like Listeria.

Vancomycin and ciprofloxacin: systemic antibiotic administration for peritoneal dialysis-associated peritonitis.

OBJECTIVES: Peritonitis due to peritoneal dialysis (PD) is best treated empirically while waiting for the results of the dialysate culture. Thus, antibiotic therapy must cover both gram-positive and gram-negative micro-organisms. First, over a period of 9 years in a multicenter study we evaluated the efficiency of a vancomycin and ciprofloxacin combination given as the first-line treatment protocol for PD peritonitis. Second, we evaluated whether a systemic route of administration of the antibiotics could be an interesting alternative to the usual cumbersome intraperitoneal drug administration. METHODS: Vancomycin 15 mg/kg body weight, intravenous, and oral ciprofloxacin 250 mg two times per day (500 mg twice per day if residual creatinine clearance was above 3 mL/minute) were prescribed at diagnosis of peritonitis. Vancomycin injections were repeated (when blood trough level was expected to be below 12 microg/mL) in cases of gram-positive organisms for a total duration of 3 weeks. Ciprofloxacin was given for a total of 3 weeks in cases of gram-negative and a total of 10 days for susceptible gram-positive infections. RESULTS: A total of 129 episodes of peritonitis occurred; 28 of them were not included in the study because of protocol violation (n = 15) or fungal (n = 7) or fecal (n = 6) peritonitis, leaving 101 peritonitis episodes for analysis. 52 (51.5%) gram-positive and 28 (27.7%) gram-negative organisms were grown; 38 gram-positive organisms were coagulase-negative staphylococci. No organism was identified in 8 peritonitis episodes, whereas 13 peritonitis episodes were caused by more than 1 organism. 35% of the coagulase-negative staphylococci were resistant to first-generation cephalosporin and methicillin, whereas all were susceptible to vancomycin. For gram-negative bacilli, the susceptibility rate was 96% and 95% for ciprofloxacin and ceftazidime respectively. The overall treatment success rate was 77.2% (78 of the 101 peritonitis episodes): 61.4% at first intention and 15.8% after optimization of the antibiotic therapy (second intention). The protocol failed in 22.8% of the peritonitis episodes. Hospitalization was required in 52% of the peritonitis episodes; average hospitalization was 11 (range 1-45) days. CONCLUSION: Systemic vancomycin and ciprofloxacin administration is a simple and efficient first-line protocol antibiotic therapy for PD peritonitis. In our opinion, vancomycin should still be used for gram-positive infections because of its high susceptibility rate compared with first-generation cephalosporins, providing a close monitoring of the local epidemiology. Oral ciprofloxacin provides satisfactory results in gram-negative infections, comparable to those obtained with intraperitoneal ceftazidime or aminoglycosides.