Cervical lymph node diameter reflects disease progression in multiple sclerosis

Background: Multiple sclerosis (MS) is an autoimmune disease against the central nervous system (CNS), where B cells activate in the deep cervical lymph nodes (CLNs) before migrating to the CNS. CLN diameter in head magnetic resonance imaging (MRI) is an unexplored possible biomarker for disease activity. Methods: We measured CLN axial diameter from head MRIs of patients with active stable relapsing-remitting MS (a-RRMS-stable, n = 26), highly active stable RRMS (ha-RRMS-stable, n = 23), RRMS patients directly after a relapse (RRMS-relapse, n = 64) and follow-up MRIs from the same patients (r-RRMS-follow-up, n = 26). MRIs of primary headache syndrome patients (n = 38) served as a control group. We evaluated the correlation between CLN diameter and clinical data. Results: Increases in EDSS in approximately 2 year-follow up after imaging was connected to smaller CLN diameter at imaging (correlation coefficient −0.305, p = 0.009). In a regression model, age did not show a significant effect to CLN diameter in MS patients. Enlarged CLNs of over 10 mm diameter were more common in patients with shorter disease duration (p = 0.013). The largest CLN axial diameter in RRMS-relapse group was smaller than in the control group (p = 0.005), whereas MS subgroups of the study did not differ in CLN diameter. Conclusions: CLN diameter appears to reflect disease duration and disease progression in MS, in line with compartmentalization of immunological activity to the CNS in time. Decrease in CLN diameter was seen also during relapse. CLN axial diameter in MRI shows promise as a feasible biomarker for assessing MS disease activity.