Next-Generation Sequencing for Pathogen Detection and Quantification in Children With Musculoskeletal Infections

Plasma-Based Next-Generation Sequencing for Pathogen Detection and Quantification in Children With Musculoskeletal Infections

The purpose of this study is to evaluate the use of a blood test: Karius® plasma-based next-generation sequencing test (Karius Test), to see if we can detect and measure the infection causing agent in children with musculoskeletal infections (MSKI).

children admitted to Riley Hospital for Children (RHC) with musculoskeletal infections (osteomyelitis, septic arthritis, or pyomyositis) over a 12-month period will be prospectively enrolled. Eligible subjects will be identified by referral from the infectious diseases and orthopedic services at RHC. Blood samples will be obtained on the day of admission (within 48hrs), and 24 hours after the admission sample for real-time NGS (next-generation sequencing) testing at Karius Laboratory (Redwood City, CA). If a pathogen is identified by NGS, in either of the first two samples, subsequent samples will be sent every 48-72 hours while inpatient, and then collected every 1-2 weeks after hospital discharge, while being treated for MSKI (maximum 3 follow-up samples). If both of the initial inpatient NGS samples are negative, no further samples will be sent for NGS. Pathogen identification by NGS will be compared to standard cultures methods, and quantitative cfDNA (cell-free DNA) will be evaluated over time.

Inclusion Criteria:

1. 6 months (to ensure adequate blood volume drawn) to 18 years of age.
2. Strong clinical suspicion of MSKI as evidenced by fever, osteoarticular pain (e.g. tenderness to palpation of a joint, bone pain, or refusal to bear weight); and elevated ESR (erythrocyte sedimentation rate) or CRP (C-reactive protein).

Exclusion Criteria:

• Subjects will be excluded if they have clinical evidence suggesting an alternative diagnosis; inability or unwillingness to consent for the study