Thrombotic Microangiopathy Associated with Macrophage Activation Syndrome: A Multinational Study of 23 Patients.

OBJECTIVE: To describe the clinical characteristics, treatment, and outcomes of a multinational cohort of patients with macrophage activation syndrome (MAS) and thrombotic microangiopathy (TMA). STUDY DESIGN: International pediatric rheumatologists were asked to collect retrospectively the data of patients with the co-occurrence of MAS and TMA. Clinical and laboratory features of patients with systemic juvenile idiopathic arthritis (sJIA)-associated MAS and TMA were compared with those of an historical cohort of patients with sJIA and MAS. RESULTS: Twenty-three patients with MAS and TMA were enrolled: 17 had sJIA, 2 systemic lupus erythematosus, 1 juvenile dermatomyositis, 1 mixed connective tissue disease, and 2 undifferentiated connective tissue disease. Compared with the historical cohort of MAS, patients with sJIA with coexistent MAS and TMA had higher frequencies of renal failure and neurologic involvement, hemorrhage, jaundice, and respiratory symptoms, as well as more severe anemia and thrombocytopenia, higher levels of alanine aminotransferase, lactate dehydrogenase, bilirubin and D-dimer, and lower levels of albumin and fibrinogen. They also required admission to the intensive care unit more frequently. Among patients tested, complement abnormalities and reduced ADAMTS13 activity were observed in 64.3% and 44.4% of cases, respectively. All patients received glucocorticoids. Treatment for TMA included plasma-exchange, eculizumab, and rituximab. CONCLUSIONS: The possible coexistence of MAS and TMA in rheumatic diseases may be underrecognized. This association should be considered in patients with MAS who develop disproportionate anemia, thrombocytopenia, and lactate dehydrogenase increase, or have multiorgan failure.

Methotrexate therapy may prevent the onset of uveitis in juvenile idiopathic arthritis.

OBJECTIVE: To evaluate whether early treatment with methotrexate (MTX) prevents the onset of uveitis in children with juvenile idiopathic arthritis. STUDY DESIGN: The clinical charts of all consecutive patients seen between January 2002 and February 2011 who had a disease duration <1 year at first visit and had received a stable management for at least 2 years with or without MTX were reviewed. Patients who were given systemic medications other than MTX (except nonsteroidal anti-inflammatory drugs) were excluded. Patients with systemic arthritis, rheumatoid factor-positive arthritis, or enthesitis-related arthritis were also excluded. In each patient, the 2-year follow-up period after first visit was examined to establish whether uveitis had occurred. RESULTS: A total of 254 patients with a median disease duration of 0.3 year were included. Eighty-six patients (33.9%) were treated with MTX, whereas 168 patients (66.1%) did not receive MTX. During the 2-year follow-up, 211 patients (83.1%) did not develop uveitis, whereas 43 patients (16.9%) had uveitis a median of 1.0 year after the first visit. The frequency of uveitis was lower in MTX-treated than in MTX-untreated patients (10.5% vs 20.2%, respectively, P = .049). Survival analysis confirmed that patients treated with MTX had a lower probability of developing uveitis. CONCLUSION: Early MTX therapy may prevent the onset of uveitis in children with juvenile idiopathic arthritis. Because our study may be affected by confounding by indication, the potential of MTX to reduce the incidence of ocular disease should be investigated in a randomized controlled trial.