title: Rituximab therapy has a rapid and durable response for refractory cytopenia in childhood-onset systemic lupus erythematosus.
abstract: OBJECTIVE
  Autoimmune thrombocytopenia (AITP) and hemolytic anemia (AIHA) are common in childhood-onset systemic lupus erythematosus (cSLE) and may be refractory to conventional therapies. Our objectives were to: (a) examine our experience; (b) determine the rate and durability of response to rituximab; and (c) evaluate its safety in our cSLE population with refractory cytopenias.
  
  
  METHODS
  We performed a single-center retrospective cohort study of cSLE patients with refractory AITP or AIHA treated with rituximab between 2003 and 2012. Outcomes included the time to complete clinical response, time to B-cell depletion, duration of response and time to flare. Adverse events were also analyzed.
  
  
  RESULTS
  Twenty-four (6%) of 394 cSLE patients received rituximab for refractory cytopenia. The indication was AITP in 16 (67%), AIHA in five (21%) and both in three (13%) patients. The median (interquartile range (IQR)) time from cytopenia onset to rituximab therapy was 16 (7-27) months for AITP and 10 (2-29) months for AIHA. Complete response following the first course of rituximab occurred at a median (IQR) of 48 (14-103) days, only one patient failed to respond. Five (21%) patients had one or more flare episodes at 22 (15-27) months. Infusion reactions were rare and one infection with herpes zoster required hospitalization in the first 12 months. Three of four patients with low IgG levels prior to the first rituximab course developed persistent hypogammaglobulinemia, and three patients have required intravenous immunoglobulin replacement.
  
  
  CONCLUSIONS
  Rituximab appears to be a well-tolerated, safe and long-lasting therapy for cSLE patients with refractory AITP and/or AIHA. Caution should be exercised when considering rituximab for patients with preexisting hypogammaglobulinemia.
authors: Division of Rheumatology, Hospital for Sick Children, Canada.
authors: M
authors: M
authors: Olfat
authors: Division of Rheumatology, Hospital for Sick Children, Canada University of Toronto, Canada.
authors: E D
authors: ED
authors: Silverman
authors: Division of Rheumatology, Hospital for Sick Children, Canada University of Toronto, Canada deborah.levy@sickkids.ca.
authors: D M
authors: DM
authors: Levy
mesh_terms: D000293:Adolescent; D000361:Agammaglobulinemia / Q000188:drug therapy; D017668:Age of Onset; D000744:Anemia, Hemolytic, Autoimmune / Q000097:blood / Q000188:drug therapy* / Q000473:pathology; D018501:Antirheumatic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D001402:B-Lymphocytes / Q000276:immunology; D002648:Child; D015331:Cohort Studies; D005260:Female; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000627:therapeutic use; D016130:Immunophenotyping; D008180:Lupus Erythematosus, Systemic / Q000097:blood* / Q000188:drug therapy* / Q000276:immunology; D008297:Male; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000097:blood / Q000188:drug therapy* / Q000473:pathology; D012074:Remission Induction; D012189:Retrospective Studies; D000069283:Rituximab / Q000009:adverse effects / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D018501:Antirheumatic Agents; D016756:Immunoglobulins, Intravenous; D000069283:Rituximab
keywords: B-cell depletion; Systemic lupus erythematosus; hemolytic anemia; hypogammaglobulinemia; rituximab; thrombocytopenia