Successful Therapeutic Approach to Facial Hyperpigmentation Secondary to Addison's Disease: A Case Report and Literature Review.

Addison's disease, or primary adrenal insufficiency, is a rare endocrine disorder characterized by deficient glucocorticoid and mineralocorticoid production, frequently associated with cutaneous hyperpigmentation due to chronic elevation of adrenocorticotropic hormone. Facial hyperpigmentation may persist despite adequate hormonal replacement, representing a therapeutic challenge with limited evidence to guide dermatologic management. We report the case of a 41-year-old female patient with an eight-year history of progressive hyperpigmentation affecting the face, hands, and oral mucosa. Physical examination revealed severe facial involvement with brown-violaceous macules and associated telangiectasias. The patient had a prior diagnosis of autoimmune ovarian failure in 2017 and was diagnosed with Addison's disease in 2020, receiving stable glucocorticoid replacement therapy. Histopathological evaluation demonstrated basal layer hyperpigmentation without interface dermatitis, consistent with endocrine-related pigmentation and overlapping melasma features. A multimodal therapeutic approach was implemented, including picosecond Nd:YAG laser therapy (approximately seven sessions at six- to eight-week intervals), oral tranexamic acid (250 mg twice daily), and a topical depigmenting regimen containing tranexamic acid, niacinamide, retinoids, and antioxidants. The patient demonstrated a significant reduction in modified Melasma Area and Severity Index score from 19.8 to 7.8 (60.6% reduction), along with a marked improvement in quality of life, as evidenced by a posttreatment Melasma Quality of Life Scale score of 20/70. This case highlights that persistent hyperpigmentation in Addison's disease may not fully resolve with endocrine treatment alone and may require adjunctive dermatologic interventions. A personalized, multimodal strategy targeting multiple pathogenic pathways, including melanogenesis, plasmin-mediated signaling, vascular factors, and dermal pigment deposition, can achieve significant improvement, even in patients with darker phototypes and long-standing disease. These findings underscore the importance of a multidisciplinary approach and suggest a potential role for combination therapies, including laser-based modalities, in managing complex pigmentary disorders associated with systemic conditions. Further studies are needed to establish standardized treatment protocols and evaluate long-term outcomes.