If you are having gut problems, that could cause your counts to tank. If the probiotics help your gut, I would think that would be a good thing. Some gut problems are made worse by probiotics (I've got one of those) so I wouldn't be surprised if they affected my counts in a bad way but you said you were doing better, so it's hard to think of how the probiotics could cause it. But remember, probiotics and other over the counter herbs, meds, etc. tend to not be well documented in terms of their possible adverse effects - so maybe.
Erica
And she was!
Diagnosed May 2005, lowest count 8K.
4/22/08: 43K (2nd Rituxan)
10/01/09: 246K, 1/8/10: 111K, 5/21/10: 233K
Latest count: 7/27/2015: 194K