Bactericidal and synergistic activity of double-carbapenem regimen for infections caused by carbapenemase-producing Klebsiella pneumoniae

Available therapeutic options against carbapenem-resistant Klebsiella pneumoniae (CR-Kp) are limited because of the high level of resistance to other antimicrobial classes including polymyxins. The double-carbapenem regimen has been recently considered a possible therapeutic strategy. In the present study, we evaluated the in vitro bactericidal and synergistic activity of a double-carbapenem regimen consisting of ertapenem plus high-dose meropenem in a series of patients with healthcare-associated CR-Kp infections in whom the use of colistin was not indicated because of potential nephrotoxicity and/or resistance. In vitro synergy was evaluated using checkerboard and killing studies. A total of 15 patients were included in the study, with sepsis, severe sepsis and septic shock found in two (13.3%), five (33.3%) and one (6.7%) patients, respectively. Overall, the clinical/microbiological response was 12/15 (80%). Synergy was observed in 11/14 (78.6%) isolates using the checkerboard method whereas in killing studies 12/14 (85.7%) and 14/14 (100%) strains were synergistic and bactericidal at 24 h at concentrations of 1 × MIC MEM+1 × MIC ERT and 2 × MEM+1 × MIC ERT, respectively, with a significant decrease of log CFU/mL compared with other combinations (p <0.0001). The double-carbapenem regimen showed clinical and in vitro effectiveness in patients with CR-Kp infections.

The role of IL-15 in challenging Acquired Immunodeficiency Syndrome

OBJECTIVE

To determine the functions of in vitro primed Natural Killer (NK) cells in Human Immunodeficiency Virus (HIV-1) infection and the role of IL-2, IL-12 and IL-15 in enhancing the NK survival and activity in terms of viral suppression and of purging of HIV provirus.

METHODS

Peripheral Blood Mononuclear Cells (PBMCs) and CD4+ T lymphocytes cells obtained from eight healthy donors were infected in vitro with HIV-1 and p24 was measured with and without IL-2, IL-12 and IL-15. We studied the effect of NK pulsed in vitro with IL-2, IL-12 and IL-15 on HIV replication by measurement of p-24 and DNA-provirus load when added into the culture of PBMCs and CD4+ T lymphocytes cells infected in vitro. We evaluated the effect of NK cells pulsed with IL-2, IL-12 and IL-15 on HIV replication and DNA-load into the culture of CD4+ T lymphocytes cells and PBMCs by trans-well chamber.

RESULTS

We found high levels of p24 in the supernatants of PBMCs and CD4+ T lymphocytes cells cultured with IL-2, IL-12, and IL-15. We observed a significant reduction of p24 in the culture both of infected PBMCs and CD4+ T lymphocytes cells in which was added NK pulsed with IL-15. We did not obtain the some results with NK pulsed with IL-2 and IL-12. We observed a power effect of NK pulsed with IL-15 on HIV-DNA. The trans-well chamber experiments showed that the effect of NK is both direct and both mediated by realizing of soluble factors.

CONCLUSIONS

This study highlights some important effects of IL 15 on NK in HIV patients anyway our results are preliminary and descriptive and others studies will be needed to provide rationale for immune therapies.

Surgical debridement with muscle flap transposition and systemic teicoplanin therapy for infected hip arthroplasty

The use of muscle flaps is now accepted as a method for coverage of infected wounds. To obtain complete eradication of infection following hip arthroplasty surgery is combined with antibiotic treatment. Aggressive debridment to remove devitalized tissue followed by vastus lateralis muscle flap transposition may improve the likelihood of success in certain challenging cases. We report two cases of prosthetic joint infection treated by aggressive debridment and vastus lateralis transposition with associated appropriate antibiotic therapy. Complete recovery of functional status was observed.