Updated Role of High-frequency Ultrasound in Assessing Dermatological Manifestations in Autoimmune Skin Diseases

Abstract

Autoimmune skin diseases are a group of disorders that arise due to the dysregulated immune system attacking self-antigens, causing multiple tissue and organ lesions. With disease progression, the physical and psychological health of patients may be seriously damaged. High-frequency ultrasound is non-invasive, reproducible, and suitable for visualizing the fine structure of external organs. The usage of high-frequency ultrasound has increased in recent years in the auxiliary diagnosis and monitoring of various skin diseases; it serves as a promising tool for dermatological disease assessment. This review summarizes the characteristics of high-frequency ultrasound imaging in common autoimmune skin diseases, including systemic lupus erythematosus, scleroderma, psoriasis, dermatomyositis, and pemphigus/pemphigoid. The objective of this review is to provide new ideas and strategies for dermatologists to diagnose and track the prognosis of autoimmune skin diseases.

Fig. 1

(a) In the sclerotic phase, the thickness of the cutaneous layer and subcutaneous layer in systemic scleroderma lesions is decreased slightly compared with the surrounding normal skin, and the echogenicity is higher. (b) Atrophic phase: the skin is atrophic and sunken, the subcutaneous fat layer disappears, and the echo increases.

Fig. 2

(a) Psoriatic lesions: The epidermis is thickened and hyperechogenic, the dermis is thickened and hypoechoic, and there is an anechoic band at the dermoepidermal junction (85). (b) In patients with psoriatic lesions, colour Doppler ultrasound reveals a highly vascular pattern within the dermis of psoriatic plaques (27). Red represents the blood flow of arteries.

Fig. 3

In dermatomyositis lesions, epidermal thickening and echo enhancement are noted, and banded hypoechoic areas can be seen in the superficial dermis (43).

Fig. 4

(a) In lupus panniculitis, a slightly hyperechoic ovoid pseudo–mass–like lesion, wrapped by the surrounding subcutaneous fat with a thin hypoechoic edge, is seen. (b) In lupus panniculitis, colour Doppler ultrasound demonstrates enhanced blood flow signals (55). Red represen ts arteries and blue represents veins.

Fig. 5

(a) In patients with pemphigus lesions, semi-arcuate anechoic areas with clear borders in the epidermis and a distinct hyperechoic line at the base of the anechoic area can be seen (43). (b) In patients with pemphigoid lesions, a continuous intact epidermis and oval hypoechogenic areas beneath the epidermis (white arrow) with clear borders are present (59).