Psychocutaneous Disorder

The Current Management of Delusional Parasitosis and Dermatitis Artefacta

Caroline S. Koblenzer, MD

Skin Therapy Letter. 2010


Introduction:

Patients who present with delusional parasitosis or dermatitis artefacta are not easy for dermatologists to work with, whose treatment requires the use of drugs unusual to the dermatologist and a significant investment of the clinician's time.

Each is a skin manifestation of a psychiatric disorder that represents a psychological defense - a way for the patient to avoid the acknowledgment of psychiatric pathology.

Delusions of Parasitosis

The delusions seen in dermatology are "systematized" or non-bizarre - i.e., they are fixed beliefs that, though false, control the patient's feelings and behavior in ways that are wholly consistent with the content of those beliefs. Delusions of parasitosis associated with cutaneous dysesthesia.

The delusional patient is often defensive, angry, and distrusting. The patient desperately wants answers. "We do not know the cause, but we have treatments that are effective" or "We have seen other patients with similar symptoms, and whatever is the cause, there are changes in the skin that we can treat" are possible answers.

Intensive topical measures are helpful (e.g., tar or bleach baths, emollients, and antibiotics as indicated). Topical agents, such as pramoxine hydrogen chloride cream or lotion, may be used to provide temporary relief of any dysesthesia.

Antipsychotic drugs are the first-line treatment (Much smaller doses than those used). Pimozide has long been the drug of choice. Risperidone and aripiprazole are preferable to olanzapine.

50–90% of patients are reported to have near or full symptom resolution, with improved functioning and any psychiatric and physical comorbidities tend to improve in parallel.

Dermatitis Artefacta

Dermatitis artefacta refers to skin lesions produced by the patient, under the veil of secrecy, to satisfy an unconscious need to be taken care of.

Lesions that are morphologically bizarre, often geometric in outline, destructive, and reportedly of sudden, mysterious yet fully formed appearance. Patients with neurotic excoriations usually have depression or anxiety with obsessive-compulsive features; those with Munchausen's syndrome have a sociopathic personality, while patients with dermatitis artefacta are most commonly diagnosed with the borderline personality disorder.

Dermatologic support is important, borderline patients are best treated psychiatrically, though a recommendation for psychiatric referral must be approached very judiciously. The antipsychotics are the drugs of choice and aripiprazole has an advantage in that it also has antidepressant properties.

Discussion:

Because patients with delusional parasitosis and dermatitis artefacta do not accept the need for psychiatric treatment, they fall either to the lot of the dermatologist or receive no help at all.

An optimal approach includes frequent short clinic visits, expression of empathy, affirmation that the skin itself is involved, and low dose antipsychotic drugs. With compliance, remissions of varying length occur, but both disorders are likely to last life-long.