Sir,We present a case of an 18-year-old woman without any relevant past medical history, who exhibits a verrucous brown plaque in her pubic area. She refers a 2 year evolution of the lesion with gradual increase in size, despite daily hygiene of the region [Figure 1].
Figure 1
Appearance of the lesion before cleansing
Appearance of the lesion before cleansingDuring the physical examination, cleansing with an alcohol swab was performed, removing part of the lesion, therefore confirming the diagnosis of terra firma-forme dermatosis (TFFD); we proceed to clean the region and completely remove the lesion [Figure 2]. Skin appeared normal, and biopsy was not necessary.
Figure 2
Disappearance of the lesion after cleansing with isopropyl alcohol
Disappearance of the lesion after cleansing with isopropyl alcoholTFFD derives from the Latin words terra firma, which means, dry land due to the appearance of the lesions, also known as Duncan dirty dermatosis, after the doctor who described this condition in 1987.[1]The etiology of this condition is unknown, but it has been hypothesized that its formation is caused by a keratinization disorder with abnormal maturation of the keratinocytes, melanin retention, and the compact of scales.[2]TFFD is underrepresented in the literature and since its description in 1987, 75% of the literature has been published in the last 5 years.[3]The classic clinical presentation is an asymptomatic papillomatous plaque that varies in color from brown to black and is observed in neck, face, torso, and ankles, especially in children and adolescents under 12 years.[3]The diagnosis is clinical and confirmed as well as treated by removal of the lesion with 70% isopropyl alcohol. A biopsy is usually not necessary, but if taken, an acanthosis with papillomatosis and lamellar hyperkeratosis is observed, which tend to form compact orthokeratotic coils with the absence of parakeratosis or inflammatory infiltration.[4]The differential diagnosis includes other dirty appearance skin diseases such as dermatosis neglecta, vagabond disease, X-linked ichthyosis, tinea versicolor, confluent and reticulated papillomatosis, and acanthosis nigricans, among others.[5]Pérez-Rodríguez et al. adapted the model proposed by Tan to create an algorithm as a tool to help identify lesions with a dirty aspect that are difficult to diagnose.[5]The treatment in this dermatosis is based on informing the patient about the benign nature of the lesion and the removal with isopropyl alcohol.[5]We concluded that TFFD is a benign condition that may cause anxiety in patients and their parents because of its presentation and location, in some cases generating social stigma because of the “unhygienic” appearance it produces. This is the second case of TFFD in the pubic area reported in the literature; the first one was reported in 1997 by Raveh et al.It is important to make a good interrogatory to rule out other dirt-like dermatosis, mainly dermatosis neglecta which is associated to a psychiatric condition, physical disability, or neurological deficit. Its prompt recognition may bring relief to the patients and relatives and may prevent unnecessary diagnostic procedures and aggressive treatments.
Figure 1
Figure 2