ORCAS Study: Kappa Free Light Chains in Cerebrospinal Fluid for Detecting Inflammation

ORCAS is a prospective, multicenter, real-world diagnostic study evaluating kappa free light chains (FLCκ) in cerebrospinal fluid as a biomarker for intrathecal immunoglobulin synthesis. The dataset includes 1052 paired CSF and serum samples collected from six laboratories in Germany, with 624 samples meeting the final inclusion criteria. The study, authored by Marie Süße and last updated in March 2026, reports sensitivity and negative predictive value for FLCκ in detecting intrathecal Ig synthesis and oligoclonal bands.

Use Cases

• Validate the sensitivity of FLCκ as a biomarker for intrathecal immunoglobulin synthesis based on the reported metrics.
• Compare the diagnostic performance of FLCκ against established markers like oligoclonal bands.
• Assess the utility of FLCκ in a real-world, multi-center clinical laboratory workflow.
• Investigate the negative predictive value of FLCκ for ruling out intrathecal inflammation.

Strengths

• Includes 1052 paired cerebrospinal fluid and serum samples from a real-world clinical setting.
• Data is from a prospective, multicenter study conducted across six laboratories in Germany.
• Reports specific performance metrics, including a sensitivity of 0.87 and a negative predictive value of 0.97 for detecting intrathecal Ig synthesis.

Limitations

• Row count for the final analytical dataset is unknown; only the initial sample count (1052) and final included sample count (624) are provided.
• Column-level documentation is absent; field semantics must be inferred after download.
• The primary endpoint of sensitivity >0.95 was not met, indicating the biomarker may not be suitable as a standalone test.

Provenance

Source

Marie Süße via figshare.

Collection Method

Prospective nationwide real-world diagnostic study (ORCAS) with samples analyzed according to local laboratory standards.

Freshness

Last updated 2026-03-18 05:21:24.

Geography

Germany.