I am having the same issue periodically. And the ONLY solution to fix it (temporary) is to reboot. As far as I remember it was happened to me on 4.4.2, 4.4.3 and now on 4.4.4.
BBS shows nothing major. There are no rouge processes in memory (checked in terminal), CPU deep sleep is fine (another fact saying that this cannot be a wake-lock). LTE/GSM signal is good and consistent (same place all the time). I have tried an airplane mode when drain has started but it does not matter.
If drain has started - phone would loose about 20% overnight (8-9 hours) when completely idle. Normally it should be 2-3%.
So, the source of such high drain is more likely somewhere in hardware/drivers etc.
I cannot determine which part of the hardware is draining current - baseband processor, digitizer, busmux, DAC or else...
PS: so much for all that google gimmicks about battery life improvement in every new Android OS.
Speaking of which I find out that Google Services in 4.4.4 are always trying to connect to "mother ship" even if Data Connection is turned down.
Some google developer explained algorithm they use for framework communications like this: if connection is failed then double wait time and repeat until it reached max wait time around 30min.
Well, last night (7 hours), with data connection explicitly turned off through Android Settings UI, Google Framework attempted to report to "central office" 246 times! - max wait time was about 1 minute and half.
Clearly, developers of framework know nothing about Android Settings API and continue "pinging" - well, but this is another problem.