Prognostic value of free light chains lambda and kappa in early multiple sclerosis.

Area of Science:

• Neurology
• Immunology
• Biomarker Research

Background:

• Cerebrospinal fluid (CSF) immunoglobulin free light chains (FLC) are explored as a quantitative alternative to oligoclonal bands (OCB) for multiple sclerosis (MS) diagnosis.
• Limited data exists on the prognostic role of FLC in predicting disease progression, especially in early MS stages.

Purpose of the Study:

• To evaluate the prognostic significance of FLC in patients with OCB-positive clinically isolated syndrome (CIS) and early MS.
• To assess the association of FLC with clinical and MRI-based markers of disease progression.

Main Methods:

• CSF and serum KFLC and LFLC levels were measured using nephelometry in 61 CIS/MS patients and 60 controls.
• Clinical follow-up and 3T MRI (T2 lesion load, percent brain volume change) were conducted over a median of 4.8 and 2.2 years, respectively.

Main Results:

• CSF FLC levels were significantly elevated in CIS/MS patients compared to controls (p < 0.001).
• A lower CSF KFLC/LFLC ratio was associated with conversion from CIS to clinically definite MS (CDMS) (HR=2.89, p < 0.05).
• No significant correlations were observed between FLC variables and MRI measures (T2LL, PBVC).

Conclusions:

• Intrathecal synthesis of FLC is confirmed in CIS/MS, supporting their diagnostic utility.
• The CSF KFLC/LFLC ratio demonstrates prognostic value in CIS, potentially exceeding that of OCB for predicting MS conversion.