Dear Editor:
Dermatosis neglecta (DN) is characterized by localized hyperkeratinization as a consequence of avoiding proper washing of the affected areas1. It is more common in patients with physical disability, neurological deficit, or psychiatric illness who are likely to lack cleanliness and also in patients with unconscious failure to clean adequately due to pain, hyperesthesia, or prior trauma23. Herein, we introduce a case of DN caused by incorrect use of a moisturizer.
A 23-year-old woman presented with a 3-week history of heavy whitish glittering scales over periorbital areas (Fig. 1A). The lesions resembling squama gradually grew in its thickness and size. The patient had no previous medical problems except for rosacea, which was treated with oral doxycycline, topical metronidazole and a moisturizer to avoid facial skin dryness. Upon history taking we found that she had an inappropriate habit of applying the moisturizer very excessively as well as cleansing her face too softly. Based on suspicion of DN, we applied urea cream for 5 minutes. Afterwards, gentle rubbing with cotton swabs removed the lesions completely, leaving normal skin (Fig. 1B). No recurrence was seen after 2 months.
A typical characteristic of DN is a dirty appearance, secondary to the progressive accumulation of sebum, sweat, corneocytes, and other debris, resulting in hyperpigmented, waxy plaques with cornflake-like scales23. Since its appearance easily mimics other diseases, the exact diagnosis is important to prevent unnecessary procedures and treatment. The differential diagnosis includes psoriasis, acanthosis nigricans, confluent and reticulated papillomatosis, verrucous nevi, terra firma-forme dermatosis, Darier's disease and ichthyosis24. Histopathologic examination may be helpful in challenging cases, demonstrating orthokeratotic hyperkeratosis, papillomatosis, mild acanthosis, and anastomosing rete ridges without significant inflammation25. For treatment, water cleansing with soap or alcohol swabbing is mostly enough to remove the lesion, but as in our case, keratolytic agents such as urea, salicylic acid, or lactic acid can also be employed2.
Interestingly, our patient showed a distinctive feature, which had not been previously reported in literature, presenting shiny whitish scales instead of dirt-like brown lesions. The white scaly skin usually seems not to be unclean. It commonly arises in inflammatory skin conditions as well as normal dry skin. Therefore, describing DN as an unwashed dermatosis is more relevant than calling it a dirty dermatosis. In addition, the fact that the color of the lesions was identical to that of the moisturizer suggests that DN can exhibit varied presentations, especially in color, according to which material remains on the affected region. The most important differential points are whether a patient has physical, psychological, or environmental factors leading to an inadequate washing habit and whether the lesions are effectively cleared with normal cleansing. Our patient demonstrated an obsessive behavior to apply the moisturizer due to her excessive concern about underlying rosacea.
In conclusion, we describe an interesting case of DN induced by a patient's inappropriate utilization of a moisturizer. This case implies the possibility for DN to have multifarious clinical features.