Psychocutaneous Diseases at a Glance
- Primarily Psychiatric Disorders
- Delusional: Delusions of Parasitosis, Body Dysmorphic Disorder.
- Factitial: Dermatitis Artefacta, Dermatitis Para-Artefacta (Trichotillomania, Skin Picking), Malingering.
- Somatoform: Body Dysmorphic Disorder, Atypical Pain/burning, Hypochondriasis, Somatization.
- Obsessive Compulsive Disorders.
- Affecting approximately 5% of dermatology patients.
- Variable degree of insight, mostly poor.
- Mostly self-induced lesions.
- Poor prognosis if untreated.
- Quality of life severely deteriorated.
Scientific advances are shedding new light on the understanding and treatment of long-recognized conditions located at the interface of dermatology and psychiatry. Both arising from ectoderm, the skin and the nervous system are connected by more than just their common origins. The skin is one of the major avenues by which humans perceive the world, and, in turn, are perceived by it. When these perceptions go awry, great distress may result. When the skin is markedly affected by a primary dermatologic condition, psychological sequelae in the form of comorbidity often follow, greatly impacting patient quality of life.
The central nervous system (CNS) can influence the health of other organ systems, including the skin. Psychophysiologic mechanisms for this interaction range from the stress responses mediated by neuroadrenal connections and associated changes in immunologic function, to the systemic and local action of various neuropeptides and neurohormones.1,2
Between 20% and 40% of patients seeking treatment for skin complaints have some type of psychiatric or psychological problem causing or complicating the presenting symptoms.3,4 A large number of these patients lack insight into the possible psychogenic origin of their symptoms and are often reluctant to accept any kind of psychiatric referral. Therefore, in the absence of a psychiatry liaison clinic in the dermatologic setting,4 the dermatologist must be familiar with the most common of these diagnoses, their clinical manifestations (both psychological and dermatologic), and the basic principles of treatment. When approaching these issues, it is important to explore psychiatric, and particularly psychotic, symptoms as well as compliance with medications. Collateral informants such as family members can be quite helpful if the patient grants permission. Lastly, the effects of patient symptoms on familial and social life can be of much assistance in understanding the issues to be addressed.
Following the original description of C. Koblenzer,5 psychocutaneous diseases can be classified on the basis of their primary etiology as:
- Primary psychogenic disorders, which can present with a variety of symptoms and behaviors, usually characterized by self-injury, that can lead to perceived or actual dermatologic conditions, or
- Primary dermatologic disorders that can be either triggered or amplified by contextual causes (e.g., life stresses or interpersonal relationships) that may lead to psychiatric comorbidities such as, anxiety, depression, and distress through their impact on physical appearance and well being. In some instances, the psychiatric comorbidities are not merely the result of the detrimental aspects of skin, but are associated to the pathophysiology of the dermatological disease itself. An example of the latter is ...