Drug-induced Delusional Infestation

It is considered that certain drugs might induce delusional infestation, yet, to date, no studies have been performed to identify the pharmacodynamics associated with these treatments. The aim of this review is to summarize current available knowledge of drug-induced delusional infestation. A literature search was performed for primary studies on suspected drugs reported to induce delusional infestation. Included articles were evaluated systematically using the Naranjo criteria. In addition, drug mechanisms of action were compared. The final selection included 31 studies, in which a total of 26 classes of drugs were identified. Anti-Parkinson drugs were most frequently associated with delusional infestation, followed by antidepressants, antiepileptics, antibiotics, prescription stimulants, and a few other drug groups. The current available literature suggests that the onset of delusional infestation is initiated by drug-induced alterations in neurotransmitter levels, predominantly dopamine, in the central nervous system.

Delusional infestation: Clinical presentations, diagnosis, and management

BACKGROUND

Delusional infestation is a primary psychiatric disorder characterized by a somatic-type delusional disorder (primary delusional infestation) that may lead to self-induced cutaneous lesions which are often difficult to recognize and treat properly. It may be also secondary to other psychiatric disorders, medical diseases, or substance abuse.

AIMS

This review will describe prevalence, common clinical features, different clinical presentations, differential diagnoses, and treatment recommendation. Special focus has been put on psychological aspects.

METHODS

We conducted a literature search on PubMed from January 2001 to June 2020 with the search terms of delusional parasitosis, delusional infestation, psychological, Reference lists of identified articles were examined for further relevant studies. The search was limited to English language articles. No specified quality criteria were used for study inclusion.

RESULTS

The clinical manifestations of delusional infestation are very important in the differential diagnosis and its psychological implications and management perspectives.

CONCLUSION

This article presents an update regarding the clinical aspects and treatment options of delusional infestation in order to provide an up-to-date review for dermatologists and general practitioners.

Historical and clinical considerations on Ekbom's syndrome

Ekbom's syndrome represents a relatively uncommon neuropsychiatric condition characterized by the recurrent and bizarre fixed delusional belief to be infested by small organisms or even unanimated materials ('Morgellons disease'), without any objective evidence of infestation/parasitosis. The condition, mainly diagnosed in a nonpsychiatric setting, is supposed to be largely underestimated and, hence, undermanaged. The present comprehensive review aims at investigating Ekbom's syndrome, from a historical, epidemiological, clinical and therapeutic perspective, by providing diagnostic-treatment strategies in managing this condition in routine psychiatric clinical settings. The prototypical patient is a middle-aged woman (or a younger subject in those cases in which substance and/or alcohol abuse is implicated), often single, divorced or widowed (loneliness component and social withdrawal), who has already consulted several specialists due to skin lesions associated with a firm and delusional belief to be infested. The identification and diagnosis are challenging due to poor patient's insight, poor knowledge and collaboration between specialists and differential diagnoses to be considered before asking for a psychiatric referral. Management and treatment strategies mainly derive from isolated case reports or observational studies with a small sample size. Further randomized clinical trials should be performed to evaluate the efficacy of newer antipsychotic drugs, including long-acting injectable formulations.

Delusional infestation: the case for improved mental state testing

OBJECTIVES

Delusional infestation may present as a primary disorder or secondary to another disorder (e.g. schizophrenia). In this report we focus on the issue of inadequacies in mental state examinations leading to diagnostic uncertainty.

METHODS

Case studies were identified for this review through searching the academic databases MedLine, PSYCInfo and PubMed. We developed a template that contained 36 headings and independently examined each case study report. Our percentage agreement for the first 42 case studies we reviewed was 91%.

RESULTS

We identified diagnostic uncertainty due to inadequacies in the reporting of mental state examinations.

CONCLUSIONS

Clinicians need to provide mental state information to an adequate standard that would allow confirmation of a diagnosis of delusions of infestation or exclude other possibilities.