What medical condition would have deliberate sleep deprivation as a symptom?
This could be a symptom of some mood-altering antidepressants. Many tricyclic antidepressants happen to suppress REM sleep, providing additional evidence for a link between mood and sleep. Similarly, tranylcypromine has been shown to completely suppress REM sleep at adequate doses. Sleep deprivation is a form of torture and if it is self-induced than I imagine it can be very painful. I would recommend seeing a doctor if you are experiencing it.