Background: Mycobacterium nebraskense is a rare, slow growing nontuberculous mycobacterium species with limited documented cases. This systematic review aims to comprehensively analyze the clinical characteristics, presentation, and management of M. nebraskense infections by analyzing the available literature, including a newly reported case that we present in this article. Methods: A comprehensive search was conducted using PubMed and Google Scholar to identify relevant cases up to October 2023. Only seven reported cases were found, highlighting the scarcity of information on this pathogen. Results: Our analysis revealed several key findings. First, gender disparities were observed, with females being more susceptible to M. nebraskense infections. Additionally, a significant portion of patients presented with asymptomatic infections. Most affected individuals were over the age of 60, emphasizing potential age-related susceptibility. Comorbidity profiles varied widely among cases, and patients with preexisting lung comorbidities were at an increased risk of infection. The decision to treat or observe depended on clinical presentation, with even immunosuppressed individuals not always requiring treatment. Regarding treatment, we proposed an empirical approach with amikacin, clarithromycin, or rifabutin, considering the reported resistance to doxycycline and minocycline. Combination therapy was commonly employed to minimize resistance development, consistent with mycobacterial infection management. Conclusion: This study underscores the need for further research to validate these findings and enhance our understanding of M. nebraskense infections. As limited data are available, this review aims to provide valuable insights into a rare and emerging pathogen to guide clinical practice and future research endeavors.
Half a Century in Hiding: A Unique Case of Tuberculoid Leprosy with an Unprecedented Incubation Period
Abstract MSC (a.k.a. mesenchymal stem cell or medicinal signaling cell) cell therapies show promise in decreasing mortality in acute respiratory distress syndrome (ARDS) and suggest benefits in treatment of COVID-19-related ARDS. We performed a meta-analysis of published trials assessing the efficacy and adverse events (AE) rates of MSC cell therapy in individuals hospitalized for COVID-19. Systematic searches were performed in multiple databases through November 3, 2021. Reports in all languages, including randomized clinical trials (RCTs), non-randomized interventional trials, and uncontrolled trials, were included. Random effects model was used to pool outcomes from RCTs and non-randomized interventional trials. Outcome measures included all-cause mortality, serious adverse events (SAEs), AEs, pulmonary function, laboratory, and imaging findings. A total of 736 patients were identified from 34 studies, which included 5 RCTs (n = 235), 7 non-randomized interventional trials (n = 370), and 22 uncontrolled comparative trials (n = 131). Patients aged on average 59.4 years and 32.2% were women. When compared with the control group, MSC cell therapy was associated with a reduction in all-cause mortality (RR = 0.54, 95% CI: 0.35-0.85, I 2 = 0.0%), reduction in SAEs (IRR = 0.36, 95% CI: 0.14-0.90, I 2 = 0.0%) and no significant difference in AE rate. A sub-group with pulmonary function studies suggested improvement in patients receiving MSC. These findings support the potential for MSC cell therapy to decrease all-cause mortality, reduce SAEs, and improve pulmonary function compared with conventional care. Large-scale double-blinded, well-powered RCTs should be conducted to further explore these results.
364. Individualized Prognostics in COVID-19 Facilitated by Computer Recognition of Blood Leukocyte Subsets
Abstract Background To determine whether CBC differentials of COVID+ inpatients can predict, at admission, both maximum oxygen requirements (MOR) and 30-day mortality. Methods Based on an approved IRB protocol, CBC differentials from the first 3 days of hospitalization of 12 SARS CoV-2 infected patients were retrospectively extracted from hospital records and analyzed with a privately owned Pattern Recognition Software (PRS, US Patent 10,429,389 B2) previously validated in sepsis, HIV, and hantavirus infections. PRS partitions the data into subsets immunologically dissimilar from one another, although internally similar. Results Regardless of the angle considered, the classic analysis −which measured the percentages of lymphocytes, monocytes, and neutrophils− did not distinguish outcomes (A). In contrast, non-overlapping patterns generated by the PRS differentiated 3 (left, vertical, and right) groups of patients (B). One subset was only composed of survivors (B). The remaining subsets included the highest oxygenation requirements (B). At least two immunologically interpretable, multi-cellular indicators distinguished the 3 data subsets with statistically significant differences (C, p≤ 0.05). Survivors (the left subset) showed lower N/L and/or higher M/L ratios than non-survivors (the vertical subset, C).Therefore, PRS partitioned the data into subsets that displayed both biological and significant differences. Because it offers visually explicit information, clinicians do not require a specialized training to interpret PRS-generated results. CBCs vs. outcomes - Software-analyzed CBCs vs. outcomes Conclusion (1) Analysis of blood leukocyte data predicts MOR and 30-d mortality. (2) Real time PRS analysis facilitates personalized medical decisions. (3) PRS measures two dimensions rarely assessed: multi-cellularity and dynamics. (4) Even with very small datasets, PRS may achieve statistical significance. (5) Larger COVID+ infected cohort is being analyzed for potential commercialization. Disclosures Claudia R. Libertin, MD, Gilead (Grant/Research Support)