The inflammatory myopathy with abundant macrophages presenting with abundant foam cells: one case report / 中华神经科杂志

ABSTRACT

Objective To report the inflammatory myopathy with abundant macrophages presenting with abundant foam cells in a Chinese patient.Methods A 44 year-old man with rheumatoid arthritis manifested as progressive proximal muscle weakness in the upper limbs for 13 months and in the lower limbs for 11 months.Laboratory tests showed that serum creatine kinase level was increased,whereas neither the myositis antibody nor paraneoplasma antibodies were detectable,including anti-Jo-1 antibody.Electromyogram showed a classic myogenic pattern with irritable sarcomembrane excitement.Muscle biopsies were carried out in the left and right biceps brechii in 2 months and 13 months of the disease course respectively.The muscle sections were processed with standard histological,enzyme histochemistrical and immunohistochemical workup.Results The first muscle biopsy revealed CD8 positive T lymphocytes infiltrating into major histocompatibility complex (MHC)-Ⅰ positive fibers and distributing around endomysium,accompanied with scattered necrosis and regeneration.The second muscle biopsy showed perifascicular atrophy,fragmented perimysial connective tissue,and a large amount of CD68 positive foam cells and Touton cells accumulating within perimysial connective tissues and endomysium.Some CD20 positive B lymphocytes and plasmacytes were found around perivascular space,but CD8 positive T lymphocytes were only accumulated in the endomysium.MHC- Ⅰ was darkly expressed in the sarcolemma.Conclusions Inflammatory myopathy with abundant macrophages can present with foam cells infiltrating in perimysial and endomysium.The disease can be associated with rheumatoid arthritis and refractory to corticosteroid therapy.