Hi Sharmin,
Rituximab (brand name Rituxan) is used to eradicate the B lymphocytes. This drug is often used in cancer patients after chemotherapy has been finished. It is also used in lupus and rheumatoid and other autoimmune disorders, as a way to prevent the actions of the B cells. I found an article about its use with leukemia patients who have Autoimmune hemolytic anemia (AIHA). When looking at this article, please ignore what are the effects of leukemia because this has no relevance to your son's case. What does have relevance is that use of this drug did work to counter AIHA.
http://www.nature.com/leu/journal/v16/n10/full/2402676a.htmlOur results indicate that a rituximab-based combination regimen (RCD) is highly effective in treating steroid refractory AIHA of CLL (chronic lymphocytic leukemia)....This work was made possible by research grant support to Dr Kanti R Rai from The Chemotherapy Foundation, The Edward Brodsky Fund and The Joel Finkelstein Cancer Foundation.
Basically, what was found was that this did was suppress the AIHA for a median period of 13 months in these patients. This may be an option for your son, but I would suggest that you do not try this until you have also discussed it with Dr Vichinsky. Also, my part time worker has Rituxan treatments 6 months after his chemo for lymphoma and I will ask about side effects etc. He had the treatments on Fridays and never had any problem with working his days the following Wednesdays and Thursdays.
I hope there is some improvement in your son's results this time. 50 mg is a high dose and we don't want to see him on that dose for long.