[Clinical effect of tacrolimus in the treatment of myasthenia gravis in children]

[Clinical effect of different immunosuppressive treatment regimens in children with ocular myasthenia gravis: a retrospective analysis]

OBJECTIVES

To investigate the clinical effect of different immunosuppressive treatment regimens in children with ocular myasthenia gravis (OMG).

METHODS

A retrospective analysis was conducted on 130 children with OMG who were treated in the Department of Neurology, Jiangxi Children's Hospital, from February 2018 to February 2023. According to the treatment regimen, they were divided into four groups: glucocorticoid (GC) group (n=29), mycophenolate mofetil (MMF) group (GC+MMF; n=33), methotrexate (MTX) group (GC+MTX; n=30), and tacrolimus (FK506) group (GC+FK506; n=38). Treatment outcomes and adverse reactions were compared among the groups.

RESULTS

After 3 months of treatment, the FK506 group had significantly lower scores of Myasthenia Gravis Quantitative Scale and Myasthenia Gravis-Specific Activities of Daily Living than the other three groups (P<0.05). After 3 months of treatment, the FK506 group had a significantly lower dose of prednisone than the GC group, and after 6 and 9 months of treatment, the MMF, MTX, and FK506 groups had a significantly lower dose of prednisone than the GC group (P<0.05). After 12 months of treatment, the MMF, MTX, and FK506 groups had a significantly lower incidence rate of GC-related adverse reactions than the GC group (P<0.05).

CONCLUSIONS

For children with OMG, the addition of various immunosuppressants can reduce the dosage of GC and adverse reactions. Among them, FK506 shows superior efficacy compared to other immunosuppressants in the early treatment of OMG.

Long-Term Improvement in a Chinese Cohort of Glucocorticoid-Resistant Childhood-Onset Myasthenia Gravis Patients Treated With Tacrolimus

Objectives

To evaluate the long-term outcome of tacrolimus for childhood-onset myasthenia gravis (CMG) with an inadequate response to glucocorticoids, and investigate factors associated with favorable outcomes following tacrolimus treatment.

Methods

A retrospective, observational cohort study was performed for CMG patients who had not improved satisfactorily after sufficient prednisone therapy for at least 8 weeks. All patients were given tacrolimus in doses of 2–3 mg for more than 6 months. The primary efficacy outcome was assessed using the prednisone dose, quantitative MG (QMG), and MG-activity of daily living (ADL) scores. The participants were divided into improved and unimproved groups based on changes in QMG scores to investigate the risk factors that affected tacrolimus efficacy.

Results

A total of 149 glucocorticoid resistant CMG patients were finally enrolled in our study, with 113 (75.8%) responding well to tacrolimus (defined as minimal manifestation status or better). One month after initiating tacrolimus, there was a noticeable improvement in prednisone dose, QMG, and ADL scores, which continued to improve throughout the study. More importantly, the prednisone was eventually stopped in 89 of the patients (78.8%). Thymus type [odds ratio (OR) = 3.156, 95% confidence interval (CI) 1.427–6.978; P = 0.005] and pre-intervention status (OR = 0.284, 95%CI 0.109–0.741; P = 0.010) were independent predictors of tacrolimus efficacy after controlling for confounding factors in multiple logistic regression.

Conclusion

The majority of glucocorticoid-resistant CMG patients have a good long-term prognosis after adding tacrolimus. Thymus type and pre-intervention status can serve as potential predictors affecting the efficacy of tacrolimus.