Diagnosis: Acanthosis nigricans (insulin-resistance type)
A 15-year-old female presents with a 6-month history of velvety brown thickening in the axillae, accompanied by weight gain and fatigue. Examination reveals significant hyperpigmentation and skin texture changes, raising suspicion for insulin resistance-related dermatoses.
A 15-year-old female presents with a 6-month history of velvety brown thickening in the axillae. She reports associated symptoms of weight gain and fatigue, with no prior treatments attempted for her skin condition. On examination, the axillary regions show significant hyperpigmentation and a thickened, velvety texture.Location: Bilateral axillary regions.Texture: Velvety and thickened skin.Color: Brown to black hyperpigmentation.Associated findings: Possible obesity, acanthosis in other intertriginous areas.Family history: Positive for type 2 diabetes mellitus.
The patient reports that the skin changes began approximately 6 months ago, coinciding with notable weight gain and increased fatigue. There are no known triggers for the condition, and the patient has not sought treatment previously. Her past medical history is unremarkable, but there is a notable family history of type 2 diabetes in her mother and maternal grandfather. Social history is significant for a sedentary lifestyle and a diet high in carbohydrates.Onset: Symptoms started 6 months ago.Triggers: No identifiable triggers reported.Prior treatments: None attempted.Family history: Positive for type 2 diabetes mellitus.Social history: Sedentary lifestyle with high carbohydrate intake.
Acute / First-Line ManagementWeight management: Encourage caloric restriction and increased physical activity.Topical treatments: Consider topical retinoids (e.g., tretinoin 0.025%-0.1% cream applied nightly) to improve skin texture.Metformin: May be considered for insulin resistance, starting at 500 mg orally once daily, titrating as tolerated.Workup and Diagnostic ConfirmationFasting insulin and glucose levels: Evaluate for insulin resistance.Oral glucose tolerance test (OGTT): Assess for impaired glucose tolerance or diabetes.Lipid profile: To assess for dyslipidemia associated with metabolic syndrome.Long-Term ManagementRegular follow-up: Monitor weight, skin changes, and metabolic parameters.Endocrine referral: Consider for persistent insulin resistance or metabolic syndrome.Patient education: Emphasize lifestyle modifications to prevent progression to type 2 diabetes.
Post-inflammatory hyperpigmentation: Usually follows inflammatory skin conditions; lacks velvety texture.Skin tags: Often associated with insulin resistance but are distinct lesions.Obesity-related skin changes: Can cause similar alterations but typically lack the velvety feel.Granuloma annulare: Presents as annular plaques; does not exhibit velvety thickening.Nevoid basal cell carcinoma syndrome: Rarely presents with similar skin changes; associated with other neoplasms.Familial benign pemphigus (Hailey-Hailey disease): Characterized by intertriginous lesions, but different clinical course.Acquired keratosis pilaris: Typically presents with rough, raised bumps rather than velvety thickening.
High-Yield PearlsInsulin resistance: Acanthosis nigricans is often a marker of insulin resistance and can precede the development of type 2 diabetes.Physical examination: Always assess for associated features such as obesity and other skin findings.Topical retinoids: Can improve the appearance of the skin; however, lifestyle modification is crucial for underlying metabolic issues.Metformin: Not only aids in glycemic control but also may improve skin manifestations in insulin-resistant patients.Family history: Important in assessing risk factors for metabolic syndrome and diabetes.Recognizing the connection between skin findings and systemic disease can lead to early intervention and improved patient outcomes.
Tags: acanthosis nigricans, insulin resistance