LDH should be very reliable - what is your method for inducing the inflammasome? You could consider looking at propidium iodide uptake, which is very inexpensive and easy to do. It isn't very specific, however, and if you have membrane pores open up without pyroptosis occurring you may still see signal. You could alternatively look at ASC or Caspase-1 speck formation, but these are not specific to pyroptosis, but rather indicate inflammasome assembly which usually - but not always - leads to pyroptosis.

Jordan R. Yaron Appreciate for your answer, how about tunel assays, is it can detect pyroptosis mechanism?