How do dermatologists treat acanthosis nigricans?

• Acanthosis nigricans (AN) is defined by hyperpigmented, verrucous, or velvety plaques that develop on flexural surfaces and in intertriginous areas. 

• AN is most usually seen in people with insulin resistance, particularly obesity and diabetes, and less frequently in those with other metabolic disorders, genetic syndromes, medications, and cancer. 

• Finally, the precise pathophysiology is unknown.

What diseases are associated with acanthosis nigricans?

• If you have dark patches of skin with a thick, velvety texture, you may have acanthosis nigricans. This is a fairly common skin pigmentation disorder that usually develops in skin folds, such as the back of the neck, axilla, and groin. The patches are typically symmetric and may be brown or black in color. If you think you may have acanthosis nigricans, see your dermatologist, he will:

• Identify obesity based on optimal body weight, height/weight, and BMI
• Measure the blood pressure;
• Determine fasting blood glucose and insulin levels concurrently;
• In obese patients, consider ordering HbA 1c, ALT, and a fasting lipoprotein profile;
• Consider screening for other endocrine and metabolic illnesses;
• Consider malignancy: if suspected, refer to the appropriate specialist for the best diagnostic method;
• Search medications as a possible cause;
• Consider familial/genetic illnesses as a possibility;

How do dermatologists treat acanthosis nigricans?

• There is no specific cure for AN, but there are treatments that can help improve the appearance.

First-Line Therapy: Treat the underlying cause

• Treating the underlying cause of acanthosis nigricans can make the dark patches of skin fade or even disappear. 

• This can mean stopping any medicine that's causing the problem, treating a related disease, or managing a syndrome. 

• The most effective approach is to treat any underlying conditions.

Second-Line Therapies

• The following treatments can be effective :

Tretinoin

• Topical tretinoin is an effective treatment for acanthosis nigricans, especially when used in combination with ammonium lactate cream. 

• In a study of 30 cases of idiopathic acanthosis nigricans, topical tretinoin was found to be effective in reducing hyperkeratosis and hyperpigmentation.

Adapalene

• Topical 0.1% adapalene gel has been shown to be effective in reducing hyperpigmentation and improving the appearance of the skin in a pilot study.

Tazarotene

• Tazarotene is a well-established treatment for acne vulgaris and has shown antiacne efficacy without the irritation potential of tretinoin. 

• In an isolated report, topical tazarotene 0.05% cream has been successfully used in a boy suffering from morbid obesity and acanthosis nigricans. Tazarotene may be effective in treating acanthosis nigricans.

Trichloroacetic acid

• Acanthosis nigricans is a common pigmentary disorder that can be difficult to treat. Trichloroacetic acid (TCA) peels have been shown to be a safe and effective treatment option for AN. 

• In a recent study, TCA peels were found to improve the appearance of AN lesions in patients. The study showed that TCA is a safe, easy, and effective method for the treatment of AN.

Metformin

• Metformin has been shown to be effective in treating this condition.

Ammonium lactate 12%

• Acanthosis nigricans can be improved by using a topical regimen of 12% ammonium lactate lotion or cream twice daily and 0.05% tretinoin.

Glycolic acid

• Glycolic acid peels are an effective treatment for acanthosis nigricans. The peels help to exfoliate dead skin cells and improve the appearance of the skin. 

• Maintenance is done by applying a cream containing glycolic acid, urea, and acetylated fat esters each night.

Third-Line Therapies

• There is no definitive treatment for acanthosis nigricans. Third-line therapies include:

Urea

• Urea cream has been found to be effective in treating hyperpigmentation associated with AN in adolescents, with the 20% concentration showing that urea cream may be a practical option, particularly in combination with other therapies.

Calcipotriol

• Calcipotriol is a medication that is used to treat acanthosis nigricans. Acanthosis nigricans is a condition that causes the skin to become thick, dark, and velvety. It is often associated with other diseases, such as cancer and endocrine disorders. 

• Calcipotriol works by inhibiting the proliferation of keratinocytes, which are the cells that make up the outer layer of the skin. 

• It is available in both cream and ointment form and is typically applied twice daily. Side effects may include itching, redness, and burning at the site of application.

Kligman formula

• The Kligman formulation (hydroquinone + tretinoin + dexamethasone) has been used with some success.

Melatonin

• Melatonin could improve cutaneous symptoms in obese patients with acanthosis nigricans by improving insulin sensitivity and inflammatory mechanisms.

Isotretinoin and Acitretin

• Acanthosis nigricans can be treated with oral isotretinoin or Acitretin, which are forms of vitamin A. This treatment can help to improve the appearance of the skin and reduce the thickness of the patches.

Octreotide

• Octreotide is a medication that is sometimes used to treat acanthosis nigricans. Octreotide has been shown to be effective in reducing the symptoms of acanthosis nigricans in some studies.

Dietary fish oil

• Acanthosis nigricans is a well-recognized skin condition often associated with diabetes and obesity. In a study, a woman with lipodystrophic diabetes and severe acanthosis nigricans was placed on a diet that included fish oil supplements. 

• The fish oil effectively reduced the hyperpigmentation and normalized the skin texture.

Sitagliptin and pioglitazone E

• The disappearance of AN after several months of sitagliptin and pioglitazone suggests improvement in insulin sensitivity and resolution of AN after treatment with sitagliptin and pioglitazone.

Laser long-pulsed (5m-sec) alexandrite laser and fractional carbon dioxide laser

• Laser therapy is a promising treatment option for acanthosis nigricans. 

• Alexandrite laser has been demonstrated to be effective in improving AN lesions. Alexandrite laser is a promising effective and well-tolerated treatment modality for acanthosis nigricans. 

• Pulsed dye laser (PDL) showed low efficacy in the treatment of acanthosis nigricans due to its low energy and low penetration of laser beams. 

• The fractional CO2 laser is a good effective and well-tolerated treatment modality for acanthosis nigricans.

Conclusion

• Acanthosis nigricans is a skin condition that causes brown to black, velvety patches to form on the skin. It's usually found on the back of the neck, in the armpits, groin, or other body folds. Dermatologists treat it with medicated creams, lasers, and other therapies.