Rituxan results update

I just got back my results from the blood test for levels of anti-MAG in January. Anti-MAG has thankfully fallen from the original 52,000 BTU (Buhlmann Titer Units) in October 2007 to 19,000 BTU in January 2009 following Rituxan treatments (4 in December 2007, and 3 mid year 2008). This reduction is also reflected in a reduction in the IgM electrophoresis, although not quite as much. It is still way above the normal 1000 BTU, and I suppose that more Rituxan treatments will be needed at some point, but the results are thankfully heading in the right direction (a drop of 63%).
Now…the question becomes, how does one know when more Rituxan is needed? It seems like the best gauge is IgM level, because access to the anti-MAG test is quite difficult (cost > $800 for the test).
Funny…two years ago I didn’t know what “Chronic” meant!! 🙂