Outcome of Corynebacterial Bloodstream Infection in Patients With Cardiac Implantable Electronic Devices: A Brief Report and Systematic Review.

Cardiac implantable electronic device infection in the context of corynebacterial bloodstream infection (BSI) remains poorly understood. From 2012 to 2023 at Mayo Clinic, 4 of 12 patients with corynebacterial BSI had cardiac implantable electronic device infection: 1 patient was diagnosed during a relapsing BSI episode. Undefined source, persistent BSI, and the presence of a prosthetic cardiac valve were common characteristics.

Trimethoprim-sulfamethoxazole dosing and outcomes of pulmonary nocardiosis.

BACKGROUND: Nocardia often causes pulmonary infection among those with chronic pulmonary disease or immunocompromising conditions. Trimethoprim-sulfamethoxazole (TMP-SMX) is recommended as first-line treatment, though little data exists regarding outcomes of different dosing regimens. METHODS: We performed a multicenter retrospective cohort study of adult patients with non-disseminated pulmonary nocardiosis initially treated with TMP-SMX monotherapy. Patients' initial TMP-SMX dosing was categorized as high- (> 10 mg/kg/day), intermediate- (5-10 mg/kg/day) or low-dose (< 5 mg/kg/day). Outcomes included one-year mortality, post-treatment recurrence, and dose adjustment or early discontinuation of TMP-SMX. SMX serum concentrations and their effect on management were also assessed. Inverse probability of treatment weighting was applied to Cox regression analyses. RESULTS: Ninety-one patients were included with 24 (26.4%), 37 (40.7%), and 30 (33.0%) treated with high-, intermediate-, and low-dose TMP-SMX, respectively. Patients who initially received low-dose (HR 0.07, 95% CI 0.01-0.68) and intermediate-dose TMP-SMX (HR 0.27, 95% CI 0.07-1.04) had lower risk of one-year mortality than the high-dose group. Risk of recurrence was similar between groups. Nineteen patients had peak SMX serum concentrations measured which resulted in 7 (36.8%) dose changes and was not associated with one-year mortality or recurrence. However, 66.7% of the high-dose group required TMP-SMX dose adjustment/discontinuation compared to 24.3% of the intermediate-dose and 26.7% of the low-dose groups (p = 0.001). CONCLUSIONS: Low- and intermediate-dose TMP-SMX for non-disseminated pulmonary nocardiosis were not associated with poor outcomes compared to high-dose therapy, which had a higher rate of dose adjustment/early discontinuation. Historically used high-dose TMP-SMX may not be necessary for management of isolated pulmonary nocardiosis.

Evaluation of germicidal ultraviolet-C disinfection in a real-world outpatient health care environment.

BACKGROUND: The coronavirus disease 2019 pandemic has highlighted the need for effective infection control in outpatient health care settings. Germicidal ultraviolet-C (GUV) light, known for inactivating microorganisms by damaging their deoxyribonucleic acid or ribonucleic acid, offers a potential solution. This study examines the efficacy of GUV air disinfection systems in real-world outpatient environments. METHODS: We deployed upper-room and far-UV GUV fixtures in 3 outpatient facilities, assessing their impact on bacterial loads through air and surface sampling and bioindicator tests. Occupancy was also monitored. RESULTS: While manual air and surface sampling did not show a significant difference in bacterial loads between control and Ultraviolet C-treated groups, bioindicator tests demonstrated a high level of spore inactivation (up to 99.7% for upper-room GUV and 96.26% for far-UV). Occupancy levels did not significantly influence these outcomes. DISCUSSION: The discrepancy between bioindicator efficacy and environmental sampling results suggests limitations in the latter's ability to accurately capture environmental bioburden. Bioindicators proved to be reliable for in-situ validation of Ultraviolet C surface disinfection. CONCLUSIONS: Bioindicators are effective for validating GUV surface disinfection efficacy in health care settings, though further research is needed to optimize environmental sampling methods for assessing GUV's impact on real-world bacterial loads.

Epidemiology, Timing, and Secondary Prophylaxis of Recurrent Nocardiosis.

Background: Nocardia tends to cause infection in immunocompromised patients or those with chronic pulmonary disease. Nocardia is known to recur, prompting the practice of secondary prophylaxis in patients perceived at high risk. However, few data exist regarding the epidemiology of recurrent nocardiosis or the effectiveness of secondary prophylaxis. Methods: We performed a multicenter, retrospective cohort study of adults diagnosed with nocardiosis from November 2011 to April 2022, including patients who completed primary treatment and had at least 30 days of posttreatment follow-up. Propensity score matching was used to analyze the effect of secondary prophylaxis on Nocardia recurrence. Results: Fifteen of 303 (5.0%) patients developed recurrent nocardiosis after primary treatment. Most recurrences were diagnosed either within 60 days (N = 6/15, 40.0%) or between 2 to 3 years (N = 4/15, 26.7%). Patients with primary disseminated infection tended to recur within 1 year, whereas later recurrences were often nondisseminated pulmonary infection. Seventy-eight (25.7%) patients were prescribed secondary prophylaxis, mostly trimethoprim-sulfamethoxazole (N = 67/78). After propensity-matching, secondary prophylaxis was not associated with reduced risk of recurrence (hazard ratio, 0.96; 95% confidence interval, .24-3.83), including in multiple subgroups. Eight (53.3%) patients with recurrent nocardiosis required hospitalization and no patients died from recurrent infection. Conclusions: Recurrent nocardiosis tends to occur either within months because of the same Nocardia species or after several years with a new species. Although we did not find evidence for the effectiveness of secondary prophylaxis, the confidence intervals were wide. However, outcomes of recurrent nocardiosis are generally favorable and may not justify long-term antibiotic prophylaxis for this indication alone.