There were those strange medieval holy orders in Eastern Europe. I know of one near Kiev, that,when the time came, devoted themselves entirely to prayer and nothing else, including taking care of the body. They had a cave where they were buried in the ground with only their heads above and would prey. The acolytes would care for them and feed them, barely enough to live. Naturally the conditions lead to death or a mortification of the body.
The earth must be very cold to be buried in. They didn't have to "take care of bodily functions" this just happened where they were buried, of course. I guess one of their holy men did this to himself and then they all sort of took this up. As the brothers ( future saints) died and one room was filled up they sort of closed that area off and started new ones in front. Archeologists have been unearthing these sites the last decade or two.
Could this be the scatological deaths your Eastern Saints Calender marked?
The orthodox don't have orders. There is only a 'division' in how a monastic chooses to live, within set precepts, but they all have the same manner of both practice and outlook.
1- the hermits (direct inheritors of the anchorite tradition, such as St Anthony), who live in complete isolation, except if they converge for liturgy (ie mass), or, if they take on an acolyte who will follow in their footsteps.
2- the 'idiorrythmics', who are neither hermits nor classic monks who live in a cloister. They tend to live in comfort, and some even in luxury, and are kind of looked upon with some disdain. These are becoming less common.
3- the 'cenobotics', the classic monastic, who lives in the monastery with the other monastics and are led by the abbot.
I've not come across the Kiev story you have related, but I have read of accounts where some monastics were almost insane (if not indeed insane) in their practices. The liturgical texts that I mentioned, we're usually, if I recall correctly, mainly martyrs. The τελειούται that I mentioned, more often than not, usually refers to a martyrdom, ie. execution. For example, there are references with that word in connection with swords; and s/he was put to the sword.
But, I'm intrigued now with what you wrote, I'll search for it to read up on it. Thanks!