Navigating Delusional Infestations in Dermatology

A dermatologist will manage less than 5 patients with delusional infestations every 5 years, and there is a need to understand epidemiology, build therapeutic rapport, and therapy considerations to keep in mind when patients have the feeling of being infested by animate or inanimate pathogens without medical evidence as a true infestation. In the 2024 American Academy of Dermatology Annual Meeting session “Psychocutaneous Disease: Treating the Difficult Patient,” Jenny Murase, MD, FAAD, dermatologist at the Palo Alto Foundation Medical Group and University of California San Francisco, shed light on her extensive experience and research with delusional infestations. Her portion of the session covered was called "A Rose by Any Other Name”drawing a connection to Shakespeare's famous quote, emphasizing the complexity of terminology and patient communication in the field.¹

Jenny Murase, MD, FAAD

Defining Morgellon's Disease

Murase delved into nomenclature of the term "Morgellon's disease," tracing it back to her collaboration with John Y.M. Koo, MD, FAAD, over 20 years ago. She reflects on the significance, stating, "That was the first time Morgellons disease was a term that was being used in thepress and also in medical circles."There was a nonprofit Morgellon's Research Foundation established in 2002 with 14,720 families registered in studies, however, it was terminated in 2014 because the name “delusional infestations”was coined in 2009 to include other animate or inanimate pathogens.²

Understanding Delusions and Therapeutic Strategies 

Emphasizing the critical role of rapport-building, Murase shared, "Developing that rapport is extremely important. By referring to the disease and talking about what it is... that's what we found to be the most effective in getting the patients better." She also touched on primary versus secondary psychosis with delusional infestations. The CDC says 50% of patients with delusional infestations had drugs in hair samples and 60% had underlying psychiatric diagnosis.³

She detailed the phases of patient interaction, telling Dermatology Times, "The goal is to improve the patient's condition and not convince them... that the mutual goal you have as their clinician is to improve their condition because they can't live in the state that they're in."

Murase encourages clinicians to keep a positive attitude, sit side-by-side, ask about the goal of “finding the bug or improving the condition” with the patient, and to be prepared for socially defined boundaries (like time constraints) to not be followed by the patient. She reminds clinicians that it is a big step for the patient to seek help and it is important to create the time for them. 

It is controversial to biopsy affected areas because it is a case-by-case basis on whether the clinical impression or diagnosis will change. If the decision is made to perform a biopsy, Murase encourages clinicians to let the patient choose 1 specific biopsy site. To remain solution-oriented, Murase also recommends creating a verbal contract with the patient that if the biopsy turns out negative, that the treatment focus will be on symptoms. Labs needed for further testing include CDC, CMP, TSH, Ca, HgA1C, B12, UA, toxicology screen, HIV/Hepititis C, and RPR.⁴

There are numerous psychiatric drug options available to help patients with delusional infestations including pimozide, haloperidol, risperidone, olanzapine, aripiprazole, quetiapine. Murase encourages charting to avoid terms “psychosis” or “delusions” and instead using direct quotes such as, “The patient reports seeing a parasite with 20 legs and 15 eyes emerge from her skin and fly around the room before bed.”⁵

Reflecting on patient refusal of prescribed medications, Murase shared statements that are powerful to utilize with patients including, "I will never give up on you; you never give up on me."

References

1. Murase, J. Psychocutaneous Disease: Treating the Difficult Patient. Presented at: 2024 American Academy of Dermatology Annual Meeting; March 8-12, 2024; San Diego, CA.
2. Murase JE, Wu JJ, Koo J. Morgellons disease: a rapport-enhancing term for delusions of parasitosis. J Am Acad Dermatol. 2006 Nov;55(5):913-4. doi: 10.1016/j.jaad.2006.04.042. PMID: 17052509.
3. Pearson ML, Selby JV, Katz KA, Cantrell V, Braden CR, Parise ME, Paddock CD, Lewin-Smith MR, Kalasinsky VF, Goldstein FC, Hightower AW, Papier A, Lewis B, Motipara S, Eberhard ML; Unexplained dermopathy study team. Clinical, epidemiologic, histopathologic and molecular features of an unexplained dermopathy. PLoS One. 2012;7(1):e29908. doi: 10.1371/journal.pone.0029908. Epub 2012 Jan 25. PMID: 22295070; PMCID: PMC3266263.
4. Brownstone N, Howard J, Koo J. Management of delusions of parasitosis: an interview with experts in psychodermatology. Int J Womens Dermatol. 2022;8(3):e035. Published 2022 Jul 8. doi:10.1097/JW9.0000000000000035
5. Lu JD, Gotesman RD, Varghese S, Fleming P, Lynde CW. Treatments for primary delusional infestation: systematic review. JMIR Dermatol. 2022;5(1):e34323. Published 2022 Mar 30. doi:10.2196/34323