Impact of Empirical Antimicrobial Treatment on Patients with Ventilator-Associated Pneumonia Due to Stenotrophomonas maltophilia.

This retrospective study was conducted to evaluate the characteristics and outcomes of patients with ventilator-associated pneumonia (VAP) caused by Stenotrophomonas maltophilia (S. maltophilia), focusing on the impact of appropriate empirical antimicrobial treatment. Of the enrolled 240 patients with VAP due to S. maltophilia (median age: 45 years) in a tertiary-care hospital in southern Thailand between January 2010 and December 2021, 90% had medical comorbidities and 91% had previously received carbapenems. In addition, only 45% of the patients were initially admitted to the intensive care unit. Patients administered appropriate empirical antimicrobial treatment including colistin alone and colistin plus TMP-SMX or fluoroquinolone-based regimens had significantly lower 14-day, 30-day, and in-hospital mortalities, compared with those who did not receive appropriate empirical antimicrobial treatment (21% and 2% vs. 31%; 30% and 5% vs. 44%; and 30% and 12% vs. 53%, respectively). Thus, the use of appropriate empirical antimicrobial treatments led to a significantly reduced length of hospital stay, duration of ventilation, and hospital costs. The current study suggests that the use of appropriate empirical antimicrobial treatment based on susceptibility testing without considering pharmacokinetic properties and administration dosages improves the outcomes of patients with VAP due to S. maltophilia.

Outcomes of Adjunctive Therapy with Open Arthrotomy for Patients with Septic Arthritis Due to Melioidosis: A Retrospective Study.

Melioidosis is a potentially fatal infection caused by the bacterium Burkholderia pseudomallei. Septic arthritis caused by this infection is uncommon and difficult to treat. The role of adjunctive open arthrotomy in this type of infection has not yet been elucidated. We conducted a retrospective study of patients with microbiologically confirmed melioidosis between January 2002 and December 2022. Patients with a clinical condition of septic arthritis and positive cultures for B. pseudomallei were included. Comparisons were made between patients who received adjunctive therapy with open arthrotomy with conventional standard treatment and those who did not in terms of clinical outcomes and hospital expenditures. Of the 478 patients diagnosed with melioidosis microbiological confirmation, 81 patients had septic arthritis, accounting for 17% of cases. Among these patients, only 36 (44%) underwent adjunctive therapy with open arthrotomy. The 14-day and 30-day in-hospital mortality and length of hospital stays of patients who underwent adjunctive therapy with open arthrotomy were more favorable than those of patients who did not receive adjunctive therapy with open arthrotomy; however, the difference was not statistically significant. Patients who underwent adjunctive therapy with open arthrotomy had lower hospital expenditures (antimicrobial and non-antimicrobial costs) than those who did not undergo open arthrotomy. Adjunctive therapy with open arthrotomy for patients with septic arthritis due to melioidosis was associated with favorable clinical outcomes and significantly lower hospital expenditures.

Comparative immunogenicity and neutralizing antibody responses post heterologous vaccination with CoronaVac (Sinovac) and Vaxzevria (AstraZeneca) in HIV-infected patients with varying CD4+ T lymphocyte counts.

The immune response to heterologous coronavirus disease (COVID-19) vaccination in people living with HIV (PLWH) is still unclear. Herein, our prospective cohort study aimed to compare the immune response of heterologous vaccination with CoronaVac (Sinovac) and Vaxzevria (AstraZeneca) between PLWH having CD4 counts ≤ 200 cells/µL (low CD4+) and > 200 cells/µL (high CD4+). Anti-receptor-binding domain (RBD) immunoglobulin G (IgG) levels and the percentage inhibition of neutralizing antibodies (nAbs) were analyzed at 2 and 12 weeks after immunization. Participants in the low and high CD4+ groups had mean CD4+ counts of 139 and 575 cell/µL, respectively. Two and 12 weeks after immunization, in the low CD4 group, the median anti-RBD-IgG levels were 159 IU/mL and 143 IU/mL, respectively, whereas the nAb level was 71% and decreased to 47.2%, respectively. Contrarily, the median anti-RBD-IgG levels in the high CD4+ group were 273 IU/mL and 294 IU/mL, respectively, whereas the nAb levels were 89.3% and relatively stable at 81.6%. However, although immune responses between the two study groups were not significantly different, a decline in nAb levels was observed at 12 weeks in the low CD4+ group. Therefore, a COVID-19 booster vaccine dose is suggested for immunoprotection.