B cells may play a pivotal role in the pathophysiology of DM, and reports have claimed that targeting B cells is a viable treatment option in patients with
dermatomyositis. A 20-year-old girl presented in October 2007, with few weeks' history of proximal
muscle weakness. Gottron's papules were noted on her knuckles. She had normal inflammatory markers and negative
autoantibody screen. Her CPK was 7,000 U/L (normal range 0-170) with an LDH of 1,300 U/L (normal range 266-500). EMG and muscle biopsy was consistent with active
myositis. She had normal pulmonary function tests. HRCT showed no
interstitial lung disease. She was started with 60 mg
glucocorticoids (1 mg/kg), with a good clinical response. However, any attempt to taper down the
steroid dose led to recurrence of her symptoms. The options of available immunosuppressive therapies, including the experimental usage of
rituximab, were discussed with her; averse to long-term systemic treatments, she opted to try a course of
rituximab. She had
rituximab 1,000 mg on days 0 and 14, and her
glucocorticoids were tapered in next few weeks. Now, 24 months since her
rituximab infusions, she remains in complete clinical and biochemical remission and is naïve to other
immunosuppressive agents apart from
glucocorticoids and
rituximab. Depleting peripheral B cells with
rituximab (one course) in our patient has led not only to complete resolution of muscle and
skin disease (induction) but also remains off all immunosuppressives including
glucocorticoids.