BIID is not in the DSM-IV, is it real?
Yes, Body Integrity Identity Disorder is real, even though it is not (yet) in the DMS-IV.
While several people have argued that BIID isn't real because it is not included, the official DSM Frequently Asked Questions has this to say:
Q: What does it mean if a diagnosis is not included in the DSM?
A: It only means that, as of 1994, there was not sufficient data to justify its inclusion in the DSM-IV. Just because a category is not included in DSM-IV does not necessarily mean that it is invalid, or not worthy of being a focus of research or treatment.
There are many ways diagnoses have ended up in the DSM. During the time of the publication of DSM-I and DSM-II (1952 and 1968 respectively), there was very little empirical data available about psychiatric disorders. Since the primary purpose of the early versions of the DSM was to standardize data collection administratively and to facilitate communication among clinicians, the diagnostic makeup of these early versions represented a consensus of those disorders that were being seen by psychiatrists in the United States in the 1950's and 1960's. Starting with DSM-III, with the explosion of research in psychiatry, attempts have been made to make the DSM as empirically-based as possible. While DSM-III and DSM-III-R relied primarily on expert consensus that was informed by the experts' familiarity with then-current psychiatric research, DSM-IV was developed based on a comprehensive review of the literature.
As the DSM has become increasingly more informed by research, so has the basis for inclusion of new categories in the DSM. As stated above, originally categories were included because they were felt to represent what psychiatrists were treating. In later editions of the DSM (DSM-III-R and DSM-IV), new categories were only considered for inclusion if there was significant data available to allow critical consideration of the relevant merits and risks of inclusion. In contrast, some categories that date back to older editions of the DSM may have relatively little empirical data. Thus, because the data requirement for consideration of new categories has become more stringent, some proposed categories that were ultimately rejected may have had more data available than grandfathered categories already in the DSM.
From: http://www.dsmivtr.org/2-1faqs.cfm Emphasis added