Changes in liver transaminases and EBV DNA levels are shown for patients no. 1 and no. 2 following treatment with rituximab. The timelines below the figures indicate the time points at which quantitative EBV-PCR was performed and the values that were obtained. The arrows above the timelines indicate when rituximab was administered. AST indicates aspartate aminotransferase; ALT, alanine aminotransferase; and Neg, negative.