Pretibial mucin. Histologic patterns and clinical correlation

Obesity-Associated Lymphedematous Mucinosis: Two Further Cases and Review of the Literature

“…Pretibial mucin deposition is a phenomenon that occurs in association with thyroid diseases (pretibial myxedema) or without any thyroid dysfunction (pretibial mucinosis) [1]. OALM represent a type of pretibial mucinosis, strongly associated with obesity, characterized by skin-colored to erythematous-yellowish semi-translucent papules, plaques and nodules, arising in an edematous lymphostatic skin of the lower legs, especially on the shins [1].…”

“…OALM represent a type of pretibial mucinosis, strongly associated with obesity, characterized by skin-colored to erythematous-yellowish semi-translucent papules, plaques and nodules, arising in an edematous lymphostatic skin of the lower legs, especially on the shins [1]. …”

“…The pathogenesis of this rare condition has not been fully elucidated and, to the best of our knowledge, 22 cases have been reported in the English literature and are summarized in Table 1[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]. Lymphatic stasis, stimulated by the obesity, seems to determine a local hypoxia leading to the accumulation of mucin [4].…”

“…Obesity-associated lymphedematous mucinosis (OALM) is a rare and newly recognized disorder that can clinically mimic pretibial myxedema [1, 2]. The absence of thyroid disease and histological findings can differentiate the two conditions [1].…”

Elephantiatic dermopathy

“…2) and an increased number of mast cells similar to that found in pretibial myxedema were apparent, but stains for stromal mucin were negative. The proliferation of capillary vessels in the upper dermis is unusual in Graves' disease-associated pretibial myxedema, 8 but is characteristic of lymphedema and venous stasis.…”