662 Brief communications

Journal of the American Academy of

Dermatology

patients, We have found that 10% of patients will have cutaneous problems. Allergic contact dermatitis to mi- noxidil occurred in 3.7% of patients. The instruction sheet for minoxidil (Rogaine) solution in the United States dif- fers from that for Regaine, stating that cutaneous side ef- fects occurred in 5.27% of patients (185 of 3510). These figures also included 3.44% for complications with pla- cebo solutions. Both figures are similar to our results. Au- thors of earlier studies have mentioned contact dermati- tis in passing, 1, 2 mainly without quantification of the in- cidence of thks problem. In addition, there have been a few case reports of allergy to minoxidil solution. 3, 4

The vehicle in which minoxidil is tested appears to be important. A recent report 5 suggested that propylene glycol is essential in the vehicle for detecting contact sen- sitivity. We were unable to demonstrate any reactivity to minoxidil in petrolatum (even at 5%). One patient was further tested to minoxidil in several other vehicles; the patch test results showed reactivity when propylene gly- col was part of the vehicle, although this patient also re- acled to minoxidil in methyl ethyl ketone, Therefore pro- pylene glycol and methyl e~yI ketone appear to be su~t- able bases, but petrolatum and ethanol are not. It seems likely that the tissue penetration gained with these organic bases is important not only for demonstrating contact sensitivity, but also for producing adequate tissue levels for an effect on the hair follicle.

REFERENCES 1, Rietsehel RL, Duncan SH. Safety and efficacy of topical

mmoxidfl in the management of androgenetic alopccia. J AM ACAD DERMATOL 1987;16:677-85.

2. Kreindler TO. Topical minoxidil in early androgenetic alopecia. J AM ACAD DERMATOL 1987;16:718-24.

3. Alomar A, Smandia JA~ Allergic contact dermatiti~ to mi- noxidiL Contact Dermatitis 1988; 18:5 I-2.

4. Tosti A, Bardazzi F, De Padova MP, et aL Contact derma- titis to minoxidil. Contact Dermatitis 1985; 13:275-6.

5. Lachapelle JM, Tennstedt D, Leroy B, et aL Patch testing procedures in patients suffering from suspected allergic con- tact dermatitis to minoxidil. In: Van Neste D, Laehapelle JM, Antoine JL, eds. Trends in human hair growth and alopecia research. Lancaster, UK: Kluwer Academic, 1989:267-71.

Happy face stamps: An unusual form of dermatitis artefacta

Jason K. Rivers, MD, FRCPC* New South Wales, Australia

From the Sydney Melanoma Unit, Department of Surgery, University of Sydney, Royal Prince Alfred Hospital,

No reprints available. *Current address: Jason Rivers, MD, Division of Dermatology, The

University of British Columbia, 855 W. 101h Ave., Vancouver, BC, Canada V5ZIL7.

~6/4/z621s

Fig. 1. Crusted erythematous lesions on arm.

The presence of bizarre-shaped lesions should always alert the physician to the possibility of artefactual disease. Dermatitis artefacta most often affects persons with an underlying psychological disturbance) Frequently, ~;he clinical features of the artefact are unusual, and the rea- son and mechanism for creating the artefact are difficult to elicit from the patient. The case of dermatitis artefacta presented herein suggests that, rather than being psycho- logically disturbed, the patient was merely in an inordi- nately "happy" mood when he fashioned the artefact.

A 16-year-old youth attended the Sydney Melanoma Unit for evaluation of this melanocytic nevi. Examination also revealed several erythematous crusted areas on the lateral aspects of both arms (Fig. 1). Each lesion was in the shape of a smiling face, grid several had healed to leave hypertrophic scars. Dermatitis artefacta was suspected and the patient was questioned as to how the lesions had been produced. He announced that they were caned "happy face stamps" or "smilies" and were produced by applying the heated metal end of a butane cigarette lighter to the skin. Apparently this form of decoration was not uncommon among his peer group.

REFERENCE 1, Lyell A, Cutaneous artifactual disease. A review, amplified

by personal experience. J AM ACAD DI~MAqrOL 1 979;1:391- 407.