Aggressive Herpes Zoster in Young Patients With Multiple Sclerosis Under Dimethyl Fumarate: Significance of CD8+ and Natural Killer Cells

Reactivation of Herpes Zoster in a Young Patient With Multiple Sclerosis Under Dimethyl Fumarate Treatment and Normal Lymphocyte Subsets Count: A Case Report

Herpes zoster (HZ) infection results from the reactivation of the varicella-zoster virus (VZV), which remains dormant in the dorsal root ganglia after an initial chickenpox infection. Although HZ appears more common in people with multiple sclerosis (MS) than expected in the general population, few studies have investigated this association, particularly with a normal absolute lymphocyte count (ALC). Additionally, no reported cases have discussed the clinical presentation of such patients. This report describes the case of a 26-year-old female with a known history of relapsing-remitting MS on dimethyl fumarate (DMF) treatment. She presented with a history of painful erythematous blisters, diagnosed as acute HZ infection with a normal ALC. This case provides evidence that warrants further research and attention to the management of patients with MS receiving DMF, particularly regarding infectious risks. It highlights the importance of pharmacovigilance and the potential benefits of VZV and HZ immunization in DMF recipients.

High CD4+:CD8+ ratios with herpes zoster infections in patients with multiple sclerosis on dimethyl fumarate

BACKGROUND

Dimethyl fumarate (DMF) depletes CD8+ and CD4+ T cells, and cases of herpes zoster (HZ) in patients with multiple sclerosis (MS) on DMF have been documented.

OBJECTIVES

To evaluate lymphocyte subsets in patients with MS who developed HZ on DMF (Tecfidera) compared to matched controls who did not develop HZ.

METHODS

We used linear mixed-effects models to test for differences in white blood cell count, lymphocyte percentage, absolute lymphocyte count, CD3+ percentage, absolute CD3+ count, CD4+ percentage, absolute CD4+ count, CD8+ percentage, absolute CD8+ count, and CD4+:CD8+ ratio over time in HZ and non-HZ groups.

RESULTS

Eighteen patients developed HZ while on DMF. The linear mixed-effects model for CD4+:CD8+ ratio showed a significant difference between the HZ and non-HZ groups (p = 0.033). CD4+:CD8+ ratio decreased over time in the HZ group and increased over time in the non-HZ group.

CONCLUSION

Patients with MS who develop HZ while on DMF have high CD4+:CD8+ ratios, suggesting an imbalance of CD4+ and CD8+ cells that may put a patient at risk for developing HZ while on DMF. This result emphasizes the need for lymphocyte subset monitoring (including CD4+:CD8+ ratios) on DMF, as well as vaccination prior to DMF initiation.

Fingolimod as a first- or second-line treatment in a mini-series of young Hellenic patients with adolescent-onset multiple sclerosis: focus on immunological data

BACKGROUND

Pediatric onset multiple sclerosis(POMS) is characterized by a highly active profile, often warranting treatment with high efficacy disease-modulating therapies (DMTs). Fingolimod, an oral sphingosine-1-phosphate receptor modulator, is the first Food and Drug Administration (FDA)- and European Medicines Agency (EMA)-approved DMT for the treatment of POMS.

OBJECT

Our aim is to present real-world data of seven fingolimod-treated POMS-patients, recruited in a single MS center in Greece.

METHODS

Clinical and imaging/laboratory data from 7 Hellenic patients fulfilling the International Pediatric Multiple Sclerosis Study Group (IPMSSG) criteria for POMS diagnosis, who have received fingolimod treatment, were selected. Human leukocyte antigen (HLA) genotyping was performed with standard low-resolution sequence-specific oligonucleotide techniques.

RESULTS

Three patients were treatment-naïve adolescents who received fingolimod as first-line treatment. Two experienced ongoing clinical and radiological disease activity and have been switched to natalizumab. The remaining cases were post-adolescent adults with POMS, where the vast majority experienced total/near-total disease remission. Fingolimod was generally well-tolerated. Two patients with high disease activity carried the HLA-DRB1*03 allele, while five patients were carriers of at least one of the HLA-DRB1*04, HLA-DRB1*13, and HLA-DRB1*14 alleles, which when not combined with HLA-DRB1*03 showed a trend towards a more favorable clinical course. Fingolimod responders showed a trend towards increased CD(16-56)⁺NK cell counts in immunophenotyping assays.

CONCLUSIONS

Our preliminary results support that response of POMS patients to fingolimod may be partially dependent on age and previous DMT, with younger and treatment-naïve patients presenting worse outcomes. The role of immunogenetics and immunophenotyping in personalized treatment warrants investigation in larger and more diverse populations.