672. Diagnosis of Rocky Mountain Spotted Fever Using Plasma Metagenomic Next-Generation Sequencing. (4th December 2021)

• Record Type: Journal Article
• Authors: Chiang, Leslie; Ramchandar, Nanda; Coufal, Nicole; Farnaes, Lauge; Foley, Jennifer
• Is Part Of: Open forum infectious diseases. Volume 8(2021)Supplement 1
• Page Start: S438
• Page End: S438
• Publication Date: 2021-12-04
• Subjects: Communicable diseases -- Periodicals; Medical microbiology -- Periodicals; Infection -- Periodicals; 616.9
• DOI: 10.1093/ofid/ofab466.869
• Languages: English
• ISSNs: 2328-8957

Abstract

Abstract: Background: Rocky mountain spotted fever (RMSF), caused by Rickettsia rickettsii, incurs significant morbidity and mortality, especially in children. Early in the course of illness, standard diagnostic tests are of limited sensitivity, and diagnosis is often based on clinical symptoms and local epidemiology. The diagnosis can be missed in areas where RMSF is not endemic, and a delay in initiation of therapy may lead to poor clinical outcomes. Plasma metagenomic next-generation sequencing (mNGS), with turnaround times approaching 48 hours, may be a useful adjunctive tool in the diagnosis of RMSF. Methods: We describe four children hospitalized with RMSF between January 1, 2017 to May 15, 2021 at a tertiary children's hospital in southern California. All had plasma mNGS and rickettsial serologic testing as part of clinical care. Results: mNGS detected Rickettsia rickettsii in all 4 patients. Only 2 subjects had positive serologic testing initially and required repeat testing in the convalescent stage to confirm RMSF. The mean turnaround time for mNGS was 2.75 days, which was comparable to serologic testing. Antibiotic therapy was changed in three subjects as a result of the plasma mNGS result. Conclusion: Plasma mNGS may be a useful diagnostic modality early in the disease course of RMSF. Disclosures: Lauge Farnaes, MD, PhD, Cardea Bio (Advisor or Review Panel member)IDbyDNA (Employee)