Abstract: Primary adrenal insufficiency, also known as Addison's disease, is a rare adrenal diseases closely related to autoimmune diseases that can be accompanied by various systemic manifestations, including mucosal and skin pigmentation, and even lead to adrenal crisis that endangers life. Pigmentation of oral mucosa often appears earlier than on the skin, which may be confused with other pigmentation related diseases and easily misdiagnosed in clinical practice. This article reports a case of Addison's disease with mucosal and skin pigmentation as the initial symptom. After timely diagnosis and treatment, the pigmentation completely disappeared, providing a specialty diagnosis and treatment approach with oral mucosal characteristics for this disease.

Key words: Addison’s disease, Primary adrenal insufficiency, pigmentation