Abstract: On November 30th, 2017, a 62-year-old female patient was admitted to the hospital because of multiple depigmented patches all over the body for 16 years, as well as erythema and blisters on the scalp, trunk and upper extremities for more than 8 years, which had been aggravated for 1 year. The patient underwent surgical resection of thymoma in 1996, and developed myasthenia gravis in 2004. Skin examination showed scattered erythemas of various sizes on the scalp, face, chest and upper extremities, with crusts on the surface of some erythemas and positive Nikolsky′s sign. Hypopigmented macules mingled with depigmentated macules of various sizes were scattered all over the body. A large area of depigmentation was observed on both hands, and the nail plates were atrophic. Hairs, eyebrows, eyelashes, axillary and pubic hairs were abscent. Laboratory examination showed the presence of homogeneous IgG antinuclear antibody with a titer of 1∶640, anti-double stranded DNA antibody （276 IU/ml）, lupus anticoagulant （1.62）, anti-Dsg1 antibody （> 150 U/ml） and anti-Dsg3 antibody （91 U/ml）. Histopathological examination of dorsal blister tissues and hematoxylin-eosin staining showed fissured blisters and acantholytic cells in the epidermis, monolayer basal cells on the basilar membrane, and perivascular infiltration of a few lymphocytes in the superficial dermis. The patient successively developed thymoma, vitiligo, myasthenia gravis, systemic lupus erythematosus, pemphigus vulgaris and alopecia universalis, so a diagnosis of autoimmune polyglandular syndrome type Ⅳ was made. Since autoimmune-mediated endocrinopathies are prone to occur successively, changes of related hormones and antibodies in the patient should be monitored for early diagnosis and treatment of newly emerging autoimmune diseases.

Key words: Thymoma, Vitiligo, Pemphigus, Myasthenia gravis, Lupus erythematosus, systemic, Alopecia, Autoimmune polyglandular syndrome