The use of automated data extraction tools to develop a solid organ transplant registry: Proof of concept study of bloodstream infections

Tedizolid vs Linezolid for the Treatment of Nontuberculous Mycobacteria Infections in Solid Organ Transplant Recipients

Background

Treatment options for nontuberculous mycobacteria (NTM) infections are limited by the pathogen's intrinsic resistance profile and toxicities. Tedizolid and linezolid display in vitro activity against NTM species. However, safety data and treatment outcomes are limited in the solid organ transplant (SOT) population.

Methods

This was a single-center retrospective cohort study of adult SOT recipients receiving linezolid or tedizolid for an NTM infection from January 1, 2010, to August 31, 2019. The primary outcome compared the hematologic safety profiles of tedizolid vs linezolid. We also described nonhematological adverse drug events (ADEs) and therapy discontinuation rates. In an exploratory analysis, we assessed symptomatic microbiologic and clinical outcomes in those receiving tedizolid or linezolid for at least 4 weeks.

Results

Twenty-four patients were included (15 tedizolid, 9 linezolid). No differences were identified comparing the effects of tedizolid vs linezolid on platelet counts, absolute neutrophil counts (ANCs), and hemoglobin over 7 weeks using mixed-effects analysis of variance models. ANC was significantly decreased in both groups after 7 weeks of therapy (P = .04). Approximately 20% of patients in each arm discontinued therapy due to an ADE. Seven of 12 (58%) and 2 of 3 (67%) patients were cured or clinically cured with tedizolid- and linezolid-containing regimens, respectively.

Conclusions

This study suggests no significant safety benefit of tedizolid over linezolid for the treatment of NTM infections in SOT recipients. Tedizolid or linezolid-containing regimens demonstrated a potential benefit in symptomatic and microbiologic improvement. Larger cohorts are needed to further delineate the comparative role of linezolid and tedizolid for the treatment of NTM infections in SOT recipients.

Epidemiology and risk factors for varicella zoster virus reactivation in heart transplant recipients

Heart transplant (HT) recipients are at higher risk of varicella zoster virus (VZV) reactivation. Risk factors for VZV reactivation are currently not well defined, impeding the ability to design and implement strategies to minimize the burden of this illness in this population. Automated data extraction tools were used to retrieve data from the electronic health record (EHR) of all adult HT recipients at our center between 2010 and 2016. Information from the Organ Procurement and Transplantation Network Standard Analysis and Research Files was merged with the extracted data. Potential cases were manually reviewed and adjudicated using consensus definitions. Cumulative incidence and risk factors for VZV reactivation in HT recipients were assessed by the Kaplan-Meier method and Cox modeling, respectively. In 203 HT recipients, the cumulative incidence of VZV reactivation at 8-years post-transplantation was 26.4% (95% CI: 17.8-38.0). The median time to VZV reactivation was 2.1 years (IQR, 1.5-4.1). Half (14/28) of the cases experienced post-herpetic neuralgia (PHN). Post-transplant CMV infection (HR 9.05 [95% CI: 3.76-21.77) and post-transplant pulse-dose steroids (HR 3.19 [95% CI: 1.05-9.68]) were independently associated with a higher risk of VZV reactivation in multivariable modeling. Identification of risk factors will aid in the development of targeted preventive strategies.