Tien V. Nguyen

Drug-Induced Formication and Delusions of Parasitosis

Mr. Northwood is a 25 year-old Caucasian man, who presented with a chief complaint of being infested by “bugs.” He reported intense, bothersome sensations of crawling, stinging, and biting, which were felt frequently all over this body. He otherwise had a clean bill of health and denied any psychological stress or emotional issues. Upon further questioning, he admitted to regular, heavy use of cocaine for the past 2 years. After he had started experimenting with cocaine, he started to notice these symptoms, which were tolerable at the time. However, the sensations progressively worsened to the point where he could no longer resist the urge to scratch or to pick at his skin. His general practitioner could not determine the cause, and as a result, referred him to your psychodermatology clinic for help.

Atopic Dermatitis and a Major Depressive Disorder

Ms. Reed is a 45 year-old woman with a history of chronic atopic dermatitis, which started when she was in college. At first, she reportedly experienced episodes of patchy, itchy red bumps on the extensor aspects of her arms, legs, and such episodes would get worse during exam periods. After college, she had ten blissful years without any significant atopic dermatitis episodes. However, the disease has been making a return in the past 12–13 years, gradually at first but then picking up speed in terms of frequency and viciousness of each episode. Today, the patient comes in with both arms and legs studded circumferentially with eczematous papules, which appear beefy red and noticeably warm to the touch. She reports still using her triamcinolone acetonide 0.1 % cream and emollients to the affected areas daily. You have never observed such inflammatory intensity with her skin disease before.

Neurotic Excoriations Secondary to Cutaneous Dysesthesia

Ms. Ellington is 34 year-old Caucasian woman presenting with a 1-year history of excoriations on easily reachable areas of the face, neck, dorsal hands, lateral arms, and upper chest. She had been referred to the psychodermatology clinic with an initial diagnosis of “psychosis.” There were no primary skin lesions as noted on the previous physical exam in her records. During the interview, she clearly appeared both embarrassed and apologetic about picking at her skin. She showed no elaborate ideation regarding the reason for her behavior. However, after you asked, “can you tell me exactly what makes you pick your skin?” She reports an intense focal pain in her skin as the cause.

The Distrustful and Poorly Compliant Patient

Ms. Dickinson is a 56 year-old new patient presenting with severe scalp dermatitis and psoriasiform scaling, for which a tentative diagnosis of scalp psoriasis has been made. She reports trying several topical agents, each for a few days on six different occasions over a 3-month period, with inadequate control. The referring dermatologist, who called you prior to the patient visit, is concerned that her insufficient response to therapy has been a result of poor compliance. He notes that she typically resists his treatment recommendations, and on several occasions has made blanket statements indicating her distrust of medical professionals.

The Hopelessly Delusional Patient

Ms. Daisy is a 65 year-old Caucasian new patient, who presented with a 2-year history of being infested with “parasites.” She brought with her numerous items such as impeccably prepared slides of these so-called parasite carcasses, professionally taken photographs of skin debris and other inanimate objects, and articles published in scientific journals as well as the popular press discussing parasitic infestation. She has already visited numerous dermatology practitioners and one parasitology specialist, who could not identify any ecto-parasites (i.e., those infesting visible parts of the body). Her medical history included well-controlled hypertension and chronic back pain.

The “Will You Be My PCP?” Patient

Ms. Bronte is a previously healthy 35 year-old woman, who presents to you as a new patient with sudden-onset generalized plaque-type psoriasis. She also complains of intermittent achy joints and a sensation of chest tightness that typically precedes each flare of psoriasis. She has received a thorough work-up from multiple specialists, including dermatology, rheumatology, and cardiology, at a respected medical institution prior to coming to you. In spite of having previously been diagnosed with psoriasis, she claims that her condition has not been fully diagnosed, and she worries about the risk of a cardiovascular event. Reports from cardiology and rheumatology revealed no obvious causes for her symptoms. The patient is sitting in front of you, appearing very anxious and distressed about her health, and pleads that you help control her psoriasis as well diagnose her heart and joint disease. In other words, she wants you to be her primary care physician (PCP).

Neurotic Excoriations and the Elderly

Ms. Blackburn is an 83-year-old new patient, who presents with multiple lesions over her arms and legs. She relates a history of volunteering on and off for the past that she began volunteering at a community garden 6 weeks ago, and she has recently been bitten by ants. She states that the lesions from the ant bites have become progressively worse over the past few days. Her lesions have recently demonstrated crusting and weeping of yellow discharge. The patient has come to see the dermatologist because she is concerned about infection of the lesions. She also reports she has recently become very anxious and depressed, as her husband passed away 2 months ago. On physical examination, there are multiple excoriations over the extremities. In addition, during the interview, the patient constantly scratches at her arms and legs.

The Fearful Patient

Ms. Austin is a healthy 21 year-old woman, who appears very anxious in the waiting room. She has a 2-year history of acne vulgaris unresponsive to herbal remedies, topical retinoid agents, and combined topical antibiotic/benzoyl peroxide preparations. She reports that within the past 3 months she has suffered significant discomfort and public embarrassment from the inflamed deep cysts. She is here to get a second opinion about how to improve her acne, stating that her general practitioner has done everything in his power to help her.

The Delusional but Hopeful Patient

Ms. Alvarez, a 58 year-old Hispanic woman, presented with 2 years of “infestation with bugs.” The episodes started when she stayed at her friend’s house and was reportedly exposed to dirty blankets and soiled linens. She had seen many physicians, both dermatologists and non-dermatologists. She brought in a bag full of topical medications including topical steroids, anti-fungal creams, anti-bacterial ointments, and moisturizers, none of which were of benefit. She had been treated twice with permethrine (Elimite®) by a dermatologist with only transient relief of symptoms. She described in great details the life cycle and the mating habits of these parasites. She also presented to you zip-lock bags of soiled materials containing tissue papers with brown stains suspended in cloudy water. She stated unequivocally that these specimens contain the “parasites” she has described.

The Slightly Delusional Patient

Mrs. Wang is a 69 year-old Asian American woman presenting with a chief complaint of being “infested with parasites” for the past 5 months. She described crawling, stinging and biting sensations that occurred spontaneously all over her body. There were a few plastic zip-lock bags containing what she believes to the parasites and their eggs. From her expressions and demeanor, the patient appeared deeply worried about and quite preoccupied with her infestation. However, upon further questioning Mrs. Wang stated that she was not entirely convinced about the existence of live organisms in her skin. She was open to other explanations, but above all, just wanted to receive a good treatment.