Pseudoacanthosis nigricans L83.x

Subtype of Acanthosis nigricans (benigna)

Obesity, endocrine disorders, genetic disposition.

Occurs mainly between the ages of 25 and 60, especially in dark-haired, more pigmented, obese patients. S.a.u. HAIR-AN syndrome.

Mainly intertriginous areas (axillae, thigh bends) and lateral cervical area and neck. Less frequently, the non-intertriginous areas of the trunk are affected.

Mostly symmetrical formation of initially yellow-brown to black hyperpigmentations, later on flat, velvety to sour reinforcement of the skin texture, blurred against the surroundings. Mostly hyperhidrosis with corresponding foetor. If the non-intertriginous areas of the trunk are involved, the changes are similar to those of the papillomatosis confluens et reticularis Gougerot Carteaud.

In case of prolonged persistence, development of flat or pendulous fibroma in intertriginous areas.

S.u. Acanthosis nigricans.

• intertriginous blurred black-grey verrucous plaques
• symmetrical affection of the axillae and groin regions
• first manifestation already at the age of 17 - 20 years
• very slow development over years
• obesity
• Diabetes mellitus(insulin resistance)
  • not paraneoplastic
  • mostly asymptomatic
  • itching possible

• Ichthyosis vulgaris, autosomal dominant
• Ichthyosis vulgaris, X-linked recessive
• Papillomatosis confluens et reticularis
• Darier's disease
• pemphigus vegetans
• Hailey-Hailey disease

When the body weight is normalised, the skin changes usually regress. Consistent hygiene of the intertriginous areas is necessary. Washing with syndets. Further drying measures with applications of powders or antihidrotics. Experience has shown that the compliance in these patients is not particularly high.

• Local therapy with covering, possibly zinc-containing, powders or creams for dehydration R294 as well as deodorants.
• If necessary, keratolytic external therapy with salicylic acid-containing or urea-containing creams (e.g. Salicylvaseline Lichtenstein, R102 ) as well as low doses of vitamin A acid R256.

Therapy trials with acitretin (neotigason) or isotretinoin (e.g. isotretinoin-ratiopharm; acne normin) in low dosages have been described.

Reduction of skin changes in weight reduction and meticulous care of the intertriginous spaces.