Pretibial myxoedema with autoimmunity and hyperplasia treated with glucocorticoids and surgery

Morphological Diversity of Pretibial Myxedema and Its Mechanism of Evolving Process and Outcome: A Retrospective Study of 216 Cases

“…In the largest case series, the morphology of PTM consisted of 6 variants and its subvariants. Except 6 subvariants of the plaque variant, there were also the polypoid and verrucous variants reported [17, 18]. The morphological diversity of PTM lesions was correlated with different intensity of autoimmune activity, different kinds, and frequencies of local injury and different stages of lesion-evolving process.…”

“…The infiltration characteristics of PTM meant that lymphocytes penetrated lesions of PTM and the fibrous connective tissue with excessive hyaluronan deposits and fibroblast proliferation infiltrated subcutaneous tissue and surrounding normal skin [18, 19]. The hyperplasia of PTM manifested as hyperkeratosis and acanthosis of epidermis, dermal thickening, and hypertrichosis [18].…”

“…The infiltration characteristics of PTM meant that lymphocytes penetrated lesions of PTM and the fibrous connective tissue with excessive hyaluronan deposits and fibroblast proliferation infiltrated subcutaneous tissue and surrounding normal skin [18, 19]. The hyperplasia of PTM manifested as hyperkeratosis and acanthosis of epidermis, dermal thickening, and hypertrichosis [18]. The phenomena were initiated by autoimmune reactions (humoral and cell-mediated immunity) to autoantigens (mainly TSHR) on the fibroblasts [32, 33], fibrocytes [34], and mast cells [33].…”

Prevalence and Clinical Characteristics of Pretibial Myxedema in Chinese Outpatients With Thyroid Diseases

“…Antigen-specific T lymphocytes infiltrating the pretibial lesions are of primary immune response [17], high serum levels of TRAbs are found in all PTM patients [18], TSH receptors exist on the dermal fibroblasts of pretibial skin [19], and IgG, IgA and C3 deposit in the pretibial lesions of PTM [20]. Therefore, PTM is considered to be a local autoimmune entity associated with autoimmune thyroid diseases [21,22], in which cell-mediated and humoral immunity (TRAb) plays a role in the pathogenesis [23]. The course of PTM is 10 days to 10 years and its average is 37.8 months (more than 3 years).…”

Cutaneous mucinosis in mixed connective tissue disease*

“…1,2,6,7 In refractory cases the use of intralesional or systemic corticosteroids could be effective, with the good response due to suppression of T cells, keratinocytes and fibroblasts, with a consequent reduction of the proliferation of the extracelular matrix. 8 Partial regression of nodular lesions has been reported with intralesional injection of hyaluronidase. In generalized forms thalidomide was effective in some cases and isotretinoin has been used with good response.…”