Clinical impact and cost-consequence analysis of ePlex® blood culture identification panels for the rapid diagnosis of bloodstream infections: a single-center randomized controlled trial.

To assess clinical impact and perform cost-consequence analysis of the broadest multiplex PCR panels available for the rapid diagnosis of bloodstream infections (BSI). Single-center, randomized controlled trial conducted from June 2019 to February 2021 at a French University hospital with an institutional antimicrobial stewardship program. Primary endpoint was the percentage of patients with optimized antimicrobial treatment 12 h after transmission of positivity and Gram stain results from the first positive BC. This percentage was significantly higher in the multiplex PCR (mPCR) group (90/105 = 85.7% %, CI95% [77.5 ; 91.8] vs. 68/107 = 63.6%, CI95% [53.7 ; 72.6]; p < 10- 3) at interim analysis, resulting in the early termination of the study after the inclusion of 309 patients. For patients not optimized at baseline, the median time to obtain an optimized therapy was much shorter in the mPCR group than in the control group (6.9 h, IQR [2.9; 17.8] vs. 26.4 h, IQR [3.4; 47.5]; p = 0.001). Early optimization of antibiotic therapy resulted in a non-statistically significant decrease in mortality from 12.4 to 8.8% (p = 0.306), with a trend towards a shorter median length of stay (18 vs. 20 days; p = 0.064) and a non-significant reduction in the average cost per patient of €3,065 (p = 0.15). mPCR identified all the bacteria present in 88% of the samples. Despite its higher laboratory cost, the use of multiplex PCR for BSI diagnosis leads to early-optimised therapy, seems cost-effective and could reduce mortality and length of stay. Their impact could probably be improved if implemented 24/7.

Toxoplasma gondii-specific IgG avidity testing in pregnant women.

BACKGROUND: The parasite Toxoplasma gondii can cause congenital toxoplasmosis following primary infection in a pregnant woman. It is therefore important to distinguish between recent and past infection when both T. gondii-specific IgM and IgG are detected in a single serum in pregnant women. Toxoplasma gondii-specific IgG avidity testing is an essential tool to help to date the infection. However, interpretation of its results can be complex. OBJECTIVES: To review the benefits and limitations of T. gondii-specific avidity testing in pregnant women, to help practitioners to interpret the results and adapt the patient management. SOURCES: PubMed search with the keywords avidity, toxoplasmosis and Toxoplasma gondii for articles published from 1989 to 2019. CONTENT: Toxoplasma gondii-specific IgG avidity testing remains a key tool for dating a T. gondii infection in immunocompetent pregnant women. Several commercial assays are available and display comparable performances. A high avidity result obtained on a first-trimester serum sample is indicative of a past infection, which occurred before pregnancy. To date, a low avidity result must still be considered as non-informative to date the infection, although some authors suggest that very low avidity results are highly suggestive of recent infections depending on the assay. Interpretation of low or grey zone avidity results on a first-trimester serum sample, as well as any avidity result on a second-trimester or third-trimester serum sample, is more complex and requires recourse to expert toxoplasmosis laboratories. IMPLICATIONS: Although used for about 30 years, T. gondii-specific avidity testing has scarcely evolved. The same difficulties in interpretation have persisted over the years. Some authors have proposed additional thresholds to exclude an infection of <9 months, or in contrast to confirm a recent infection. Such thresholds would be of great interest to adapt management of pregnant women and avoid unnecessary treatment; however, they need confirmation and further studies.

[Post-traumatic pulmonary aspergilloma]. / Aspergillome pulmonaire sur corps étranger résiduel post-traumatique. Diagnostic et prise en charge.

INTRODUCTION: Aspergillomas occur due to colonization of a pre-existing pulmonary, bronchial or pleural cavity by Aspergillus spp. Often asymptomatic, this pathology can reveal itself by recurrent haemoptysis or when bacterial superinfections occur. Aspergillomas occurring in post-traumatic cavities are rare and their management is poorly codified. CASE REPORT: A child suffered from a chest wound at the age of 13 years. Two years later, investigation of recurrent haemoptysis revealed a residual pneumatocele in the right lower lobe colonized by Aspergillus spp. Initial treatment with systemic azole antifungals was unsuccessful because of digestive and ophthalmological intolerance. Surgical treatment by right lower lobectomy was finally decided on by the multidisciplinary team. This revealed an intrabronchial foreign body of vegetal type with cellulosic reinforcement, causing a polymorphic granulomatous reaction around, and associated with a proliferation of filamentous fungi including Aspergillus fumigatus. Surgery was followed by liposomal amphotericin B treatment for three weeks with a favourable outcome. CONCLUSIONS: This clinical case illustrates the benefits of surgical management of post-traumatic aspergillomas, even in children, in order to eradicate the aspergillus implant and to remove any foreign body to prevent recurrence.

Impact of systemic antifungal therapy on the detection of Candida species in blood cultures in clinical cases of candidemia.

The diagnosis and follow-up of candidemia still rely on blood cultures (BCs). In vitro studies show that antifungals can significantly modify the result of blood culture not containing adsorbing agents. We aimed to evaluate, under clinical conditions, the impact on BC yeast detection of systemic antifungal therapy (SAT). Patients (n = 125) experiencing candidemia at Grenoble University Hospital (France) were included in a 4-year retrospective study. The Plus Aerobic/F (Aerobic) and Plus Anaerobic/F (Anaerobic) bottles, which both contain adsorbing resins and the non-resin selective Mycosis IC/F (Mycosis) bottles, were compared using multivariate hierarchical models adjusted for clinical characteristics. The positivity rate (PR) is decreased in patients with SAT (p < 0.01), abdominal surgery (p = 0.01), and hemodialysis (p = 0.02). In all bottles, SAT reduces PR by a factor of 0.16 (95 % CI: [0.08; 0.32]) and increases the time to positivity (TTP) by a factor of 1.76 ([1.30; 2.40]; p < 0.01). In the presence of SAT, TTP is higher in non-resin bottles (Mycosis) than in resin bottles (RR = 1.76, [1.30; 2.40]); however, the TTP in nonresin and resin bottles remains comparable. Although discordant results are observed with and without SAT (37 and 58 % respectively), we showed that the presence of SAT decreases significantly the agreement rate by a factor of 0.29 (CI: [0.12; 0.68]). The combination of Anaerobic and Mycosis bottles allowed a 100 % positivity rate for C. glabrata. SAT significantly affects BC results. Because they provide additional and complementary results, this study supports the concomitant use of resin and selective bottles, especially in patients receiving SAT.