Comparison of two doses of leucovorin in severe low-dose methotrexate toxicity - a randomized controlled trial.

Background: Leucovorin (folinic acid) is a commonly used antidote for severe toxicity with low-dose methotrexate, but its optimum dose is unclear, varying from 15 to 25 mg every 6-h.

Methods: Open-label RCT included patients with severe low-dose (≤ 50 mg/week) methotrexate toxicity defined as WBC ≤ 2 × 10^9/L or platelet ≤ 50 × 10^9/L and randomized them to receive either usual (15 mg) or high-dose (25 mg) intravenous leucovorin given every 6-h. Primary outcome was mortality at 30-days and secondary outcomes were hematological recovery and mucositis recovery.

The effect of methotrexate on neutrophil reactive oxygen species and CD177 expression in rheumatoid arthritis.

Objectives: Neutrophils are found in abundance in the synovial fluid of patients with rheumatoid arthritis (RA), where they are activated and show high reactive oxygen species (ROS) production. However, there is limited data on circulating neutrophils in peripheral blood of patients with RA in terms of ROS production, expression of activation markers and the effect of treatment with methotrexate (MTX) on ROS.

Methods: This single-centre prospective study recruited patients of RA classified as per the 2010 ACR/EULAR criteria.