Steroid-Refractory Chronic Graft-Versus-Host Disease-Associated Isolated Myositis Successfully Treated With...

Area of Science:

• Hematology
• Immunology
• Neurology

Background:

• Chronic graft-versus-host disease (cGVHD) is a significant complication of allogeneic hematopoietic stem cell transplantation (HSCT).
• Musculoskeletal involvement, specifically isolated myositis, is an exceptionally rare manifestation of cGVHD.
• This case presents a unique instance of cGVHD-associated myositis following HSCT for acute lymphoblastic leukemia.

Purpose of the Study:

• To report a rare case of cGVHD-associated myositis.
• To investigate the diagnostic features and therapeutic response in this rare condition.
• To evaluate the efficacy of ruxolitinib in steroid-refractory cGVHD myositis.

Main Methods:

• Case report of a patient undergoing allogeneic HSCT for Philadelphia chromosome-positive acute lymphoblastic leukemia.
• Clinical evaluation including assessment of muscle weakness and serum creatine kinase (CK) levels.
• Exclusion of infectious myositis and idiopathic inflammatory myopathies.
• Muscle biopsy analysis revealing inflammatory myopathy with CD3-positive lymphocytes and PD-1 expression.
• Treatment with high-dose corticosteroids followed by the addition of ruxolitinib.

Main Results:

• The patient developed fever, myalgia, and proximal muscle weakness after corticosteroid discontinuation for acute GVHD.
• Muscle biopsy confirmed inflammatory myopathy consistent with cGVHD-associated myositis.
• Initial high-dose corticosteroid therapy provided only partial clinical improvement and transient CK reduction.
• Addition of ruxolitinib led to normalization of CK levels and sustained clinical recovery.
• Ruxolitinib facilitated successful tapering of corticosteroids.

Conclusions:

• Isolated myositis is a rare but possible manifestation of cGVHD post-HSCT.
• Ruxolitinib demonstrates potential as an effective treatment for steroid-refractory cGVHD-associated myositis.
• This case expands the understanding of cGVHD complications and treatment strategies.