2009 Southern Regional Meeting Abstracts

Case Report: A 10-year old girl, after evaluation by her pediatrician, dermatologist and child psychiatrist, was referred for persistent descriptions of parasites emerging from her body. History was remarkable for atopy and anxiety that had functionally impaired her daily living. Daily shortness of breath, attributed to asthma, was treated with levoalbuterol. The patient denied sensations in association with the parasites, and had no contacts with similar complaints. Physical exam was significant only for xerosis. Microscopy and blood tests were normal except for elevated IgE to tree pollen. Cognitive errors with internally-sustained suggestions were suspected as the etiology of the delusions; treatment of the underlying anxiety disorder was recommended. The patient and her mother were not interested in medications, but did begin psychotherapy. After a period of improvement, psychotherapy was stopped, followed by a relapse of symptoms.
Delusions of parasitosis can arise from real sensations in a patient with source monitoring errors, or from suggestions in those rendered susceptible by a primary cognitive condition. In the latter case, suggestions can be sustained by rumination/obsession or by folie impose. In children with obsessive thoughts that sustain the suggestion, treatment of the underlying psychiatric condition is helpful. Folie impose resolves with removal from the environment. For source monitoring errors, treatment of the condition causing the sensation is helpful.
Many cases progress to involve both suggestions and source monitoring errors. Patients with a cognitive etiology for delusions often focus on minor skin defects and sensations as evidence of infestation, and generate wounds in an attempt to extract the perceived parasites. Patients with source monitoring errors may develop cognitive errors as well, leading to persistence of the delusion after resolution of the instigating sensation. Determining the primary etiology of the delusions can help to determine the therapy likeliest to help. However, the treatment of patients suffering with delusions remains challenging. The establishment of a therapeutic alliance is hindered by conflicts between a physician’s diagnosis and the patient’s fixed belief.