I was just reading through the ISSTD Treatment Guideslines and saw this on this topic, so posting it...
"Somatoform Comorbidity in DID
Historically speaking, somatoform disorders and dissociative disorders have been linked through the concept of hysteria and until the DSM–III were conceptualized as having similar underlying processes or mechanisms.
The DSM–III committee placed somatoform and dissociative disorders in separate categories, although this decision has been challenged (R. J. Brown, Cardeña, Nijenhuis, ¸Sar, & Van der Hart, 2007).
The International Classification of Diseases–9 (World Health Organization, 1977), however, continued to conceptualize these disorders as sharing an underlying relationship. The same is true for the International Classification of Diseases–10 (World Health Organization, 1992), which includes dissociative disorders of movement and sensation rather than conversion disorders.
High rates of somatization and somatoform disorders are found in DID patients.
Nijenhuis (1999) has characterized many of these types of symptoms as somatoform dissociation. Common somatoform symptoms in DID patients are quite varied and can include abdominal pain, pelvic pain, joint pain, face and head pain, lump in the throat, back pain,
non-epileptic seizures, and pseudo-asthma, among others.
Somatoform dissociation may explain the high rates of childhood maltreatment, particularly sexual abuse, found in patients with somatization disorder (Briquet’s Syndrome), somatoform pain disorder, hypochondriasis, and conversion disorder, particularly
non-epileptic seizures (Barsky, Wool, Barnett, & Cleary, 1994; Bowman & Markand, 1996; Goodwin & Attias, 1999; Litwin & Cardeña, 2000; Loewenstein, 1990, 2002; Loewenstein & Goodwin, 1999; McCauley et al.,
1997; Morrison"
http://www.isst-d.org/default.asp?contentID=49