Dermatitis neglecta

Dermatitis neglecta also known as unwashed dermatosis, is a skin condition that results from a lack of hygiene due to voluntary or unconscious inadequate frictional cleansing of the skin ¹. Dermatosis neglecta is characterized by papules and polygonal plaques, which are sometimes warty, brownish and hyperpigmented, adherent and symmetric, though removable with ethyl or isopropyl alcohol ². Dermatitis neglecta occurs due to inadequate skin cleansing causing progressive accumulation of sebum, sweat, keratin, cellular debris and exogenous impurities, resulting in papules, polygonal plaques and hyperpigmented adherent, localized, verrucous lesions, symmetrically distributed mainly on torso, shoulders and neck, which may be cleared with some difficulty with soap and water, and completely removed with alcohol ³.

Dermatosis neglecta skin lesions originate from a lack of or inadequate skin cleaning and exfoliation, either by neglect, hygiene carelessness, psychiatric disorders, local hypersensitivity, limbs negligence or motor paralysis ⁴. Some authors cite motor or sensory impairments, pain/hyperesthesia and immobility secondary to trauma, surgery or nerve palsy as the main triggers ⁵. There are also reports describing dermatosis neglecta as a form of dermatitis artefacta ⁶.

Dermatitis neglecta has been reported in all ages and skin types, but most commonly occurs in individuals with a physical or mental disability, or sensory disturbance, pain, trauma, or previous surgery in the affected area ⁷. Dermatitis neglecta is believed to be quite common, although there are only a handful of cases in the literature. This is likely attributable to underreporting and misdiagnosis.

The main differential diagnosis is the Terra firma-forme dermatosis (Duncan’s dirty dermatosis), a condition described in 1987 by Duncan et al. ⁸ that probably results from a keratinocyte maturation disorder leading to accumulation of keratin, sebum, sweat and melanin, with reports of adequate hygiene in the affected area. There is some controversy whether these two entities might represent different spectrums of the same pathology ⁸.

The diagnosis is made by careful dermatological examination and a propaedeutic test consisting of local friction with ethyl or 70% isopropyl alcohol, which completely clears the lesions without sequelae, displaying normal skin underneath the scrubbed area ⁴. Histopathology, rarely necessary, shows acanthosis, papillomatosis, hyperkeratosis and lamellar orthokeratosis ³.

The treatment is simple, with exfoliation, moisturizing and even rubbing of alcohol.

Table 1. Comparison between dermatosis neglecta and Terra firma-forme

Dermatosis neglecta	Terra firma-forme
Neglected hygiene	Hygiene reported as normal
Any age range	More prevalent among children
Crusted and scaly	Predominantly macular
Lamellar hyperkeratosis	Whorled hyperkeratosis
May improve with soap and water	Removed only with alcohol

[Source ² ]

Figure 1. Dermatitis neglecta on arm

Footnote: (A) Brown, dirt-like plaques on the left upper arm of a seven-year-old girl. (B) Complete resolution of the plaques after firm rubbing with 70% isopropyl alcohol.

[Source ⁹ ]

Dermatitis neglecta causes

The exact pathogenesis of dermatitis neglecta remains unclear. Inadequate exfoliation of the skin leads to the accumulation of sebum, sweat, keratin, bacteria, and other breakdown products forming a compact crust of dirt ¹⁰.

Patients often deny a lack of cleanliness.

Dermatitis neglecta symptoms

Dermatosis neglecta skin lesions are generally asymptomatic but may be cosmetically bothersome for some patients.

Clinical features of dermatitis neglecta include:

• Localized hyperpigmented patches or verrucous plaques with adherent, flaking scale
• Evolution over 2–4 months
• Involvement of trunk, genitalia, limbs, face, and surgical sites (eg after pacemaker insertion or cataract extraction) ¹¹.

Dermatitis neglecta diagnosis

Dermatitis neglecta should be suspected clinically with any localised hyperpigmented patch or plaque with a flake-like scale, especially in those with disability.

• Successful removal of crusts with isopropyl alcohol is highly suggestive ¹².
• Biopsy is usually not necessary. It shows orthokeratotic hyperkeratosis, papillomatosis, and mild acantholysis, without an inflammatory infiltrate ¹³.
• Malassezia yeast has been isolated from some lesions but likely represents commensal overgrowth rather than a causative factor ¹².

Dermatitis neglecta differential diagnosis

Dermatitis neglecta is mimicked by other localised hyperpigmented skin lesions. The main differential is Terra firma-forme dermatosis (Duncan’s dirty dermatosis), which is due to a delay in maturation of corneocytes (dead keratin-filled squamous cells in the epidermis) ¹⁴. Other conditions to consider in differential diagnosis include:

• Dermatitis artefacta
• Confluent and reticulated papillomatosis of Gougerot and Carteaud
• Acanthosis nigricans
• Verrucous epidermal nevus
• Pityriasis versicolor.

Dermatitis neglecta treatment

The patient can be reassured that no harm will be caused by gently scrubbing the skin, even where there is scarring, dysesthesia, or a pacemaker.

• Frictional washing of the affected area with isopropyl alcohol or soap and water generally produces clearing in days or weeks to months ¹⁵.
• For more severe or resistant lesions, a regimen of a keratolytic agent (for example, 20% urea, 5% glycolic acid, 12% lactic acid as a combination lotion), emollient, and daily scrubbing may be useful ¹⁵.

Dermatitis neglecta prognosis

Patients should be encouraged to wash their skin at least twice weekly ¹². Associated disorders (eg, chronic pain) should be assessed and managed. Dedicated daily light scrubbing with soap and water or isopropyl alcohol may provide effective prophylaxis in high-risk cases ¹².

References

1. Poskitt L, Wayne J, Wojnarowska F, Wilkinson JD. Dermatitis neglecta: unwashed dermatosis. Br J Dermatol. 1995; 132: 827–39. DOI: 10.1111/j.1365-2133.1995.tb00736.x https://doi.org/10.1111/j.1365-2133.1995.tb00736.x
2. Sasaya, Elisa Mayumi Kubo, Ghislandi, Carolina, Trevisan, Flávia, Ribeiro, Talita Beithum, Mulinari-Brenner, Fabiane, & Gaiewski, Caroline Balvedi. (2015). Dermatosis neglecta. Anais Brasileiros de Dermatologia, 90(3, Suppl. 1), 59-61. https://doi.org/10.1590/abd1806-4841.20153656
3. Martín-Gorgojo A, Alonso-Usero V, Gavrilova M, Jordá-Cuevas E. Dermatosis neglect or terra firma-forme dermatoses. Actas Dermosifiliogr. 2012;103:932-4.
4. Choudhary SV, Bisati S, Koley S. Dermatitis neglecta. Indian J Dermatol Venereol Leprol. 2011;77:62-3.
5. Vetrichevvel TP, Sndhya V, Shobana S, Anandan S. Dermatosis neglecta unmasking recurrence of carcinoma nasopharynx. Indian J Dermatol Venereol Leprol. 2011;77:627.
6. Martin LM, Mendes MF, Takaoka LE, Martin MM, Martin BM. Dermatosis neglecta: a report of two cases. An Bras Dermatol. 2010;85:217-20.
7. Saha A, Seth J, Sharma A, Biswas D. Dermatitis neglecta — a dirty dermatosis: report of three cases. Indian J Dermatol. 2015; 60: 185–7. doi:10.4103/0019-5154.152525
8. Erkek E, Sahin S, Çetin ED, Sezer E. Terra firma-forme dermatosis. Indian J Dermatol Venereol Leprol. 2012;78:358-60.
9. Terra firma–forme dermatosis. Pablo Fernández-Crehuet, Ricardo Ruiz-Villaverde. CMAJ Mar 2016, 188 (4) 285; DOI: 10.1503/cmaj.150075 https://doi.org/10.1503/cmaj.150075
10. Ruiz-Maldonado RR, Duran-McKinster C, Tamayo-Sánchez L, Orozco-Covarrubias ML. Dermatosis neglecta: dirt crusts simulating verrucous nevi. Arch Dermatol. 1999; 135: 728–9.
11. Panda M, Patro N, Saman S, Arora S. Dermatitis neglecta as a complication after cataract surgery. Indian J Ophthalmol 2016; 64: 231–2. DOI: 10.4103/0301-4738.181751.
12. Lucas, JL, Brodell RT, Feldman, SR. Dermatosis neglecta: A series of case reports and review of other dirty-appearing dermatoses. Dermatology Online Journal. 2006; 12(7): 5.
13. Park JM, Roh MR, Kwon JE, et al. A case of generalized dermatitis mimicking psoriasis vulgaris. Arch Dermatol. 2010; 146: 1050–1. DOI: 10.1001/archdermatol.2010.228
14. Martin-Gorgojo A, Alonso-Usero V, Gavrilova M, Jordá-Cueva E. Dermatosis neglecta or terra firma-form’e dermatosis. Actas Dermosifiliogr. 2012; 103: 932–4.
15. Saha A, Seth J, Sharma A, Biswas D. Dermatitis neglecta — a dirty dermatosis: report of three cases. Indian J Dermatol. 2015; 60: 185–7. doi:10.4103/0019-5154.152525.