Automated-red cell exchange for methaemoglobinaemia in a G6PD-deficient patient

Methaemoglobinaemia in G6PD deficiency can be managed by oxidizing agents such as methylene blue and red cell exchange (RCE). We describe a G6PD-deficient patient who presented with oxidative stress with methaemoglobinaemia and was successfully managed with automated-RCE. At presentation, the patient had anaemia, was restless, was tired and had dyspnoea. Co-oximetry showed methaemoglo-binaemia of 10.1 U/g. Further testing revealed the patient had insufficient quantities of G6PD enzyme activity (0.1 U/g Hb). In view of methaemoglobinaemia, severe G6PD deficiency and signs of haemolysis, therapeutic RCE was planned. The patient underwent two automated-RCE procedures on consecutive days, bringing down his methaemoglobin levels from 12.5 to 0.1 U/g. In each procedure, 1.5 volumes of RCE at 100% balance rate was performed using 5 units of red blood cells. The patient responded well to RCE and other supportive treatment and was off medication and doing well at day 100 of follow-up.