CFS symptoms during follow-up of three patients after first rituximab infusion. The patients had regular consultations with 1–2 month intervals, and telephone contact with 1–2 week intervals for the follow-up period. The patients kept record of their symptom development and assessed this figure, to assure that the joint interpretation of the two investigators was in accordance with their opinion. In each patient all CFS symptoms in general changed synchronously, thus the overall symptom status was subjectively scored from 1 (no symptoms) to 10 (severe symptoms) on the vertical scale. Below the figure B-cell numbers in peripheral blood are shown, for each patient, and plotted at the appropriate time during follow-up (i.e. weeks from first rituximab infusion). R: rituximab infusion. M: start of oral weekly methotrexate.