Obesity-associated lymphoedematous mucinosis

Dermatologic manifestations of thyroid disease: a literature review

Introduction

Thyroid hormone is considered one of the key regulatory hormones for skin homeostasis. Multiple organs are affected by the release of peripheral thyroid hormones (T4 and T3) further regulating various functions at a cellular level. Specifically, skin is considered an important target organ in which the thyroid hormone has a significant impact. Multiple skin diseases are associated with thyroid hormone dysregulation. However, other striking dermatologic manifestations are seen in nails and hair as well. Hypothyroidism, hyperthyroidism, and thyroid cancer can have an array of cutaneous manifestations, and we present the recent updates in this field.

Methods

A PubMed search was performed for updates in any new skin disease findings and treatments between 2010 and 2022. Research published in the past decade and previously known foundational skin findings associated with thyroid disease were presented in this review.

Conclusion

Cutaneous manifestations of thyroid disease is one of the first notable signs of thyroid hormone dysregulation. This article reviews the recent updates on the thyroid and skin interplay, and it further discusses overt visible findings and various available treatment modalities.

Insidious-Onset Indurated Plaques on the Shins

A 64-year old male presented with a several-year history of an insidious-onset tender, itchy and xerotic rash on his lower legs. Past medical history was significant for Graves’ disease and Graves’ ophthalmopathy. The examination revealed peau d’orange-appearing plaques on his shins clinically consistent with pretibial myxedema. A punch biopsy showed separation of collagen bundles with extensive dermal mucin deposition, confirming the diagnosis of pretibial myxedema. After initially failing treatment with a topical clobetasol 0.05% ointment, the patient switched to regular pentoxifylline and triamcinolone 0.1% ointment under occlusion. He remains under follow-up.

Obesity-associated lymphedematous mucinosis and stasis mucinosis

Cutaneous dermal mucinoses are a group of conditions characterized by abnormal deposition of mucin (hyaluronic acid and sulfated glycosaminoglycans) in the dermis. They can be classified either as localized or generalized forms and occur primarily or secondarily to systemic disorders. Obesity-associated lymphedematous mucinosis and pretibial stasis mucinosis are uncommon and relatively newly recognized disorders occurring in obese patients or in patients with venous insufficiency. Clinically, patients present with papules and nodules progressing to plaques and arising in an erythematous and edematous basis on the legs, especially the shins. Histopathologic examination indicates mucin deposition in the superficial portion of the dermis, angioplasia with an increase in small blood and/or lymphatic vessels, vertically running vessels, slight fibrosis, and no inflammation. Laboratory workup and histopathologic testing are helpful in differentiating these entities from pretibial myxedema (thyroid dermopathy), which represents the main differential diagnosis. Obesity-associated lymphedematous mucinosis and stasis mucinosis are not different entities but belong to a spectrum of mucinoses secondary to an increased body mass index, chronic lymphedema, and/or chronic venous insufficiency.

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

Cutaneous mucinoses are a group of conditions characterized by increased amounts of acid mucin in the dermis. They can be generalized or localized and occur isolated or in the setting of systemic diseases. Obesity-associated lymphedematous mucinosis is a distinct variant of mucinosis occurring in obese patients without any thyroid dysfunction. So far, only few cases of this rare condition have been reported in the English literature. Here, we describe two new cases and discuss some histological differences with the pretibial myxedema.

Study on Mucin in Normal-Appearing Leg Skin

Dermal deposits of mucin in the legs have been described associated with venous insufficiency. However, some degree of stasis dermatitis is generally common in aged individuals. Therefore, some amount of mucin is expected a priori in the reticular dermis of aged patients, even in the absence of clinical lesions. To test this hypothesis, the authors investigated the mucin in the legs of aged individuals without any dermatologic disease. Cutaneous samples were taken from the legs of 15 autopsy cases. A sample of the skin of the legs (either from the left or the right leg without any distinction being made) was randomly taken (without selecting any specific area or attending to macroscopical features). The skin samples were fixed in formaldehyde, and sections obtained from all samples were stained with hematoxylin and eosin, iron, and Alcian blue. Iron deposits were graded as 0/4 in 7 cases, as 1/4 in 4 cases, as 2/4 in 2 cases, and as 4/4 in 2 cases. Cases with greater deposits of iron also had other signs of stasis, such as neovascularization. All the samples scored 0 for dermal mucin deposits in the reticular dermis. The authors conclude that mucin deposits in the legs are not inherent to aging. Therefore, any mucin deposit in the reticular dermis, as well as expansion of the periadnexal dermis by mucin deposits, should be considered abnormal.

Pretibial mucinosis in an euthyroid patient

A case of exuberant pretibial mucinosis in a patient with normal thyroid function is reported. A review of literature on possible etiologies other than thyroid disease for the accumulation of mucin in the pretibial area is presented. In the patient described, it is possible that vascular insufficiency is involved. However, this is not the only factor responsible for the accumulation of mucin, since there are still unidentified causes and many patients with vascular diseases do not develop similar injuries.

Radiation therapy as part of the therapeutic regimen for extensive multilocular myxedema in a patient with exophthalmos, myxedema and osteoarthropathy syndrome: A case report

Exophthalmos, myxedema and osteoarthropathy (EMO) comprise the triad known as EMO syndrome, which is rarely observed in patients with autoimmune thyroid disease. The present study reports the case of a patient with EMO, including the response of this rare combination to radiotherapy. A 48-year-old patient with EMO syndrome presented to the Department of Radiation Oncology, University Hospital of Muenster, eight years prior to writing with therapy-resistant pretibial myxedema and hypertrophic osteoarthropathy of the metacarpal bones. The patient had been diagnosed with Graves' disease (GD) 26 years prior to presentation, which was treated by thyroidectomy and radioiodine therapy. Four years subsequent to the diagnosis of GD, the patient developed exophthalmos, which was treated using radiotherapy. An evident pretibial, foot and hand myxedema developed within the 10 years following the onset of orbitopathy. The skin lesions were treated using radiation therapy subsequent to the failure of multiple surgical procedures and medical treatments. Almost eight years subsequent to the administration of irradiation, no recurrence was observed on the lower right leg, nor was any recurrence on the lower left leg observed approximately four years subsequent to the completion of radiotherapy. However, an additional lesion on the left hand demonstrated slow progression following treatment with radiation therapy. The present study indicates that radiation therapy can be considered as adjuvant therapy for patients with refractory myxedema, to prevent or delay the recurrence of myxedema subsequent to surgical excision.

Mitochondria as therapeutic targets for cancer stem cells

Cancer stem cells (CSCs) are maintained by their somatic stem cells and are responsible for tumor initiation, chemoresistance, and metastasis. Evidence for the CSCs existence has been reported for a number of human cancers. The CSC mitochondria have been shown recently to be an important target for cancer treatment, but clinical significance of CSCs and their mitochondria properties remain unclear. Mitochondria-targeted agents are considerably more effective compared to other agents in triggering apoptosis of CSCs, as well as general cancer cells, via mitochondrial dysfunction. Mitochondrial metabolism is altered in cancer cells because of their reliance on glycolytic intermediates, which are normally destined for oxidative phosphorylation. Therefore, inhibiting cancer-specific modifications in mitochondrial metabolism, increasing reactive oxygen species production, or stimulating mitochondrial permeabilization transition could be promising new therapeutic strategies to activate cell death in CSCs as well, as in general cancer cells. This review analyzed mitochondrial function and its potential as a therapeutic target to induce cell death in CSCs. Furthermore, combined treatment with mitochondria-targeted drugs will be a promising strategy for the treatment of relapsed and refractory cancer.

Pretibial Myxedema: Case Presentation and Review of Treatment Options

Pretibial myxedema (PM) is a rare autoimmune manifestation of Graves' disease, which commonly presents as diffuse, nonpitting edema of shins and less often as plaques, nodules, or elephantiasis lesions mimicking lymphedema. We present a 57-year-old woman with 12-month history of PM, which occurred a year after treatment of Graves' disease and improved with topical corticosteroids, support stockings, and intralesional steroid injections until recurrence with local erythema and woody edema. A literature review was undertaken of the evidence-based treatment modalities for symptomatic PM: although commonly asymptomatic and self-limited, severe cases of PM may be treated with topical corticosteroid, compressive therapy, and intralesional corticosteroid injections.

Thyroid dermopathy and acropachy

Graves' disease is an autoimmune condition commonly associated with thyroid dysfunction and with anti-thyroid antibodies, usually TSH receptor stimulating antibodies. Thyroid autoimmunity also may be associated with extra thyroidal manifestations. Most common extra thyroidal manifestation is ophthalmopathy. Less common is thyroid dermopathy, usually occurring in pretibial area. Dermopathy is almost always associated with ophthalmopathy and in severe cases with acropachy. A common antigen with thyroid in tissues of the skin and the eyes, most likely TSH receptor, is involved in pathogenesis of extra thyroidal manifestations. Presence of dermopathy and acropachy are predictors of severity of autoimmune process. Local corticosteroid application is the standard therapy for dermopathy. Response to therapy is good in mild cases and poor in severe cases. Immune modulators and biotherapies are undergoing randomized trials for ophthalmopathy component of Graves' disease. Any therapy proven to be effective for ophthalmopathy can be utilized in future for management of dermopathy.

Obesity and the skin

Obesity is a serious global health problem, perhaps the biggest public health issue of our times. Excess body weight may be a factor in carcinogenesis in general, as well as contributing to the pathogenesis of metabolic, cardiovascular and musculoskeletal disorders. Obesity also has many cutaneous features, which form the basis for this review article. Many of these clinical entities are common to the majority of obese patients, e.g. striae distensae, plantar hyperkeratosis and an increased risk of skin infections. However, it may also be associated with poor wound healing, malignant melanoma and an increased risk of inflammatory dermatoses, such as psoriasis, as well as some rarer disorders. Therapeutic interventions for obesity, whether over-the-counter, prescription medicines or surgical interventions, are increasingly commonplace. All of these treatment modalities potentially have dermatological side-effects too.

Role of syndecan-3 polymorphisms in obesity and female hyperandrogenism

The heparan sulfate proteoglycan syndecan-3 (SDC3) is a novel regulator of feeding behavior and body weight. Recently, an association of SDC3 polymorphisms with obesity has been observed in Koreans. As female obesity is associated with hyperandrogenism and infertility, we studied the role of SDC3 polymorphisms in female individuals undergoing diagnostics prior to infertility treatment. For this purpose, endocrine parameters and body mass index of 249 women were assessed. Genotyping of V208I, D303N, and T329I was performed with TaqMan technology using lymphocyte-derived DNA and allelic discrimination polymerase chain reaction. Chi-square test, Student's t test, and one-way analysis of variance were used for statistical analysis. We find that an infrequent genotype and allele variation of T329I correlated with obesity (p = 0.028). Genotype and alleles of V208I were associated with luteinizing hormone (p = 0.007 and p = 0.001, respectively), luteinizing hormone/follicle-stimulating hormone (p = 0.002 and p < 0.005, respectively), 17 hydroxyprogesterone (p = 0.007 and p = 0.001, respectively), androstenedione (p = 0.046 and p = 0.013, respectively), and sex hormone-binding globulin (p = 0.021). We conclude that marked ethnic differences of the SDC3 SNP distribution in our European population could account for correlations less predominant compared to Koreans. While infrequent variations of T329I correlated with obesity, V208I was associated with endocrine parameters related to hyperandrogenism. These findings indicate that SDC3 polymorphisms could contribute to the link between female hyperandrogenism and obesity and suggest a novel potential role for SDC3 as a modulator of gonadal steroid function.