Background: Axonal degeneration is the main pathological cause of progressive neurological disability in multiple sclerosis.Serum phosphorylated neurofilament-heavy (pNF-H) can be a useful marker to monitor axonal injury in multiple sclerosis (MS), but we have to investigate their serum value in disease course, disability, radiological parameters and treatment response.

Aim of the Work
To ass whether serum pNF-H levels are related with clinical and paraclinical measures of disease severity and imaging of MS to approve this protein as a likely surrogate marker for axonal loss in MS patients.

Subjects and methods
Study included 40 patients and 40 healthy control, All patients in this study were subjected to full history taking and clinical examination including BMI, neurolological examination and scoring according to the Expanded disability status score (EDSS), routine laboratory investigations, measuring pNF-H levels

Results: the serum levels of pNF-H protein were higher in patients compared to healthy controls. The higher levels were in the progressive groups and these levels were significantly correlated with EDSS , body mass index, disease duration and age of the patients.

Conclusion The increase in pNF-H titer in the patients and during the progressive phase of the disease together with the correlation of pNF-H levels with all clinical scales indicate that cumulative axonal loss is responsible for persistant disability and that high pNF-H level is a poor prognostic value.