Clinical impact of positive Propionibacterium acnes cultures in orthopedic surgery.

BACKGROUND: The clinical significance of a positive culture to Propionibacterium acnes in orthopedic specimens remains unclear, whether about its role as a contaminant or a pathogen, or its impact as a coinfectant. Therefore, we performed a retrospective study to provide a more accurate description of the clinical impact of P. acnes in an orthopedic population aiming to determine: 1) if there is a clinical difference between P. acnes infection and contamination? 2) If there is a clinical difference between P. acnes monoinfection, and coinfection. HYPOTHESIS: There is a clinical difference between P. acnes infection and contamination. MATERIALS AND METHODS: Patients were selected over a five-year period, and those with a minimum of one positive culture for P. acnes, from any intraoperative orthopedic tissue sample, were included in the study. P. acnes infection was defined as the isolation of P. acnes from≥2 specimens, or in only one specimen, in the presence of typical perioperative findings and/or local signs of infection. RESULTS: A total of 68 patients had a positive P. acnes culture, 35 of which were considered to be infected. The infections affected mostly males (29/35-83%), occurred mostly in shoulders (22/35-63%), and at a site already containing an orthopedic implant (32/35-91%). Local inflammatory signs were present in half of the cases when an infection was diagnosed. Coinfection with other pathogens was present in 31% of patients (11/35). When comparing patients coinfected with P. acnes, and those who were monoinfected, the latter presented less often with local inflammatory signs. Recurrence rate was 24% (8/35) and the only risk factor for recurrence was the presence of a monoinfection. DISCUSSION: This study confirms the pathogenicity of P. acnes in an orthopedic population, as it is present in multiple samples in the same patient, and because it is present in cultures from cases with clinical recurrence. Our study showed that monoinfections differ from coinfections mainly by their higher risk of recurrence. LEVEL OF EVIDENCE: Level IV retrospective case series.

Extracorporeal treatment for acetaminophen poisoning: recommendations from the EXTRIP workgroup.

BACKGROUND: The Extracorporeal Treatments in Poisoning (EXTRIP) workgroup was created to provide evidence-based recommendations on the use of extracorporeal treatments (ECTR) in poisoning and the results are presented here for acetaminophen (APAP). METHODS: After a systematic review of the literature, a subgroup selected and reviewed the articles and summarized clinical and toxicokinetic data in order to propose structured voting statements following a pre-determined format. A two-round modified Delphi method was chosen to reach a consensus on voting statements, and the RAND/UCLA Appropriateness Method was used to quantify disagreement. Following discussion, a second vote determined the final recommendations. RESULTS: Twenty-four articles (1 randomized controlled trial, 1 observational study, 2 pharmacokinetic studies, and 20 case reports or case series) were identified, yielding an overall very low quality of evidence for all recommendations. Clinical data on 135 patients and toxicokinetic data on 54 patients were analyzed. Twenty-three fatalities were reviewed. The workgroup agreed that N-acetylcysteine (NAC) is the mainstay of treatment, and that ECTR is not warranted in most cases of APAP poisoning. However, given that APAP is dialyzable, the workgroup agreed that ECTR is suggested in patients with excessively large overdoses who display features of mitochondrial dysfunction. This is reflected by early development of altered mental status and severe metabolic acidosis prior to the onset of hepatic failure. Specific recommendations for ECTR include an APAP concentration over 1000 mg/L if NAC is not administered (1D), signs of mitochondrial dysfunction and an APAP concentration over 700 mg/L (4630 mmol/L) if NAC is not administered (1D) and signs of mitochondrial dysfunction and an APAP concentration over 900 mg/L (5960 mmol/L) if NAC is administered (1D). Intermittent hemodialysis (HD) is the preferred ECTR modality in APAP poisoning (1D). CONCLUSION: APAP is amenable to extracorporeal removal. Due to the efficacy of NAC, ECTR is reserved for rare situations when the efficacy of NAC has not been definitively demonstrated.

Successful prevention of respiratory syncytial virus nosocomial transmission following an enhanced seasonal infection control program.

Respiratory syncytial virus (RSV) infections can be serious in severely immunocompromised patients. Use of a targeted infection control program (TICP) has been shown to reduce RSV nosocomial transmission. We evaluated the impact of an enhanced seasonal infection control program (ESICP) vs standard TICP in a hematology-oncology ward. TICP was applied from 1999 to 2001 and ESICP applied from 2001 to 2003. ESICP consisted of strict isolation for all patients admitted on the ward during the RSV season. We prospectively evaluated the incidence, related morbidity and mortality of nosocomial RSV in both field interventions. A total of 40 hospitalized RSV infections were documented. The cumulative incidence of nosocomial RSV during TICP and ESICP was respectively of 42.8 and 3.9 cases/1000 admissions (relative risk = 0.09). ESICP needed to be implemented on 26 admitted patients on our ward to prevent one RSV nosocomial case. Furthermore, implementation of ESICP prevented four pneumonias and two deaths per RSV season. We conclude that ESICP is significantly more efficient than TICP to reduce the occurrence of nosocomial RSV infections and its related morbidity and mortality in patients with hematological malignancy and recipients of hematopoietic SCT.