Pretibial myxoedema

A Randomized Controlled Trial of Intralesional Glucocorticoid for Treating Pretibial Myxedema

BACKGROUND

Pretibial myxedema (PTM) is an uncommon dermopathy associated with autoimmune thyroid diseases. Now it is thought to be autoimmune and its treatment with glucocorticoid is helpful. However, it has not been evaluated.

METHODS

A prospective randomized controlled trial was performed in 110 patients with PTM to evaluate the efficacy and safety of triamcinolone acetonide with intralesional injection once every 3 days and once every 7 days. Randomization was performed with drawing lots and it was also stratified according to variants of PTM lesions. In the follow-up, recurrent rates were observed. The SPSS Statistics 17.0 Software was used in the statistical analysis.

RESULTS

The complete response rates were 78.2%, 83.6%, and 87.3% in regimen 1 and 50.9%, 89.1%, and 90.9% in regimen 2 at 3 weeks, 7 weeks and the end of therapy, respectively. Regimen 1 had an earlier efficacy than regimen 2, but at 7 weeks and end of therapy, there were no differences between two regimens. The majority of non-severe variants got complete response but severe variants did not. The adverse reaction rates in regimen 1 were higher and earlier than those in regimen 2. Adverse reaction occurring time in regimen 1 was shorter than that in regimen 2. Recurrent rates were 31.25% and 32% in regimens 1 and 2 at 3.5-year follow-up.

CONCLUSIONS

For its autoimmune, hyperplasia and disabled features, early treatment of PTM with glucocorticoid is necessary to get complete response. Dosage and frequency of intralesional steroid injection and lesional variants influence the efficacy of PTM. Once every 7 days is a better regimen.

Thyroid hormone and wound healing

Although thyroid hormone is one of the most potent stimulators of growth and metabolic rate, the potential to use thyroid hormone to treat cutaneous pathology has never been subject to rigorous investigation. A number of investigators have demonstrated intriguing therapeutic potential for topical thyroid hormone. Topical T3 has accelerated wound healing and hair growth in rodents. Topical T4 has been used to treat xerosis in humans. It is clear that the use of thyroid hormone to treat cutaneous pathology may be of large consequence and merits further study. This is a review of the literature regarding thyroid hormone action on skin along with skin manifestations of thyroid disease. The paper is intended to provide a context for recent findings of direct thyroid hormone action on cutaneous cells in vitro and in vivo which may portend the use of thyroid hormone to promote wound healing.

Thyroid hormone action on skin

PURPOSE OF REVIEW

To review the current understanding regarding thyroid hormone action on skin. To provide a historical context for the recent findings.

RECENT FINDINGS

Although direct thyroid hormone actions have been demonstrated on multiple aspects of cutaneous biology, rigorous study remains scant. Still, there is a slowly evolving literature supporting the concept that thyroid hormone can directly stimulate epidermis, dermis, and hair. That action may be accessed to treat cutaneous disease.

SUMMARY

Here, we review the literature regarding thyroid hormone action on skin along with skin manifestations of thyroid disease. We provide context for more recent findings of direct thyroid hormone stimulation of cutaneous cell proliferation in vitro and in vivo which may portend the use of thyroid hormone to treat cutaneous pathologies.

Localized myxedema of the foot associated with trauma and surgery

Localized extratibial myxedema is a rare presentation of thyroid disease that manifests with varied symptoms. Previous surgical or radioiodine treatment of hyperthyroidism is linked to the development of localized myxedema, as is prior trauma or surgery. We present the first known case of localized foot myxedema on a background of Graves disease following a traumatic and surgical precipitant and compare and discuss similar cases found in a literature review.

Action of topical thyroid hormone analogues on glucocorticoid-induced skin atrophy in mice

Previously we demonstrated the stimulation of collagen synthesis in triiodothyroacetic acid (TRIAC)-topically treated human and mice. In the present study, we have evaluated the dose response effect of thyroid hormone (TH) analogues and tretinoin on glucocorticoid-induced skin atrophy in a haired mouse model. For this investigation, we treated haired mice twice daily for 7 days with various topically administered doses of TRIAC, triiodothyronine-sodium salt (T(3)-Na), diiodothyroacetic acid (DIAC), 3,5-diiodothyropropionic acid (DITPA), and tretinoin with 0.2 mM betamethasone17-valerate (BM), or with the vehicle as a control group. We also investigated a combination of commercial betamethasone dipropionate (BD) 0.05% cream and various doses of TRIAC on mouse skin. TRIAC was able to reverse the skin atrophy by 25% in a daily dose of 1 nmol/cm(2) in the presence of 0.2 mM BM (p < 0.05). Neither other TH analogues nor TRIAC in lower and higher concentrations had a significant inhibitory effect on dermal atrophy (p > 0.05). A combination of 0.2 mM BM and 10 nmol/cm(2) TRIAC was able to prevent dermal atrophy by 18%. The addition of TRIAC to 0.05% BD cream in a final concentration of 0.1% was able partially to reverse the dermal atrophy by 15% (p < 0.05). TRIAC alone in a concentration of 1,000 nmol/cm(2) stimulated dermal proliferation by 34% (p < 0.05). Other TH analogues alone had no stimulatory effect on dermal proliferation. Tretinoin 0.8 mM was able to inhibit dermal atrophy by 20% (p < 0.05) and had an effect on dermal thickness of 85% (p < 0.05). However, severe side effects with edema, erythema, and scaling were commonly observed in all tretinoin-treated mouse skin, which could partly explain the increase in dermal thickness. In contrast, no skin side effects were observed after treatment with TRIAC. This study indicates that TRIAC may have a therapeutic effect on BM-induced dermal atrophy in mouse skin and a direct stimulatory effect on dermal proliferation when given alone.

Euthyroid pretibial myxedema

OBJECTIVE

To describe a case of biopsy-proven pretibial myxedema in a man with normal thyroid function.

METHODS

We present the pertinent clinical and laboratory data for the current case and review previously published information on pretibial myxedema.

RESULTS

Our patient, a 53-year-old man, had the characteristic lesions of pretibial myxedema on the anterolateral aspects of his calves. Laboratory tests showed normal thyroid function. The thyroid-stimulating immunoglobulin value was above normal. No exophthalmos or goiter was present. This uncommon dermopathy is typically associated with Graves' disease, accompanied by clinical hyperthyroidism, ophthalmopathy, and goiter.

CONCLUSION

The pathogenesis of pretibial myxedema remains elusive. It is presumed to be an autoimmune phenomenon attributable to the presence of serum thyroid-stimulating immunoglobulin, although immunofluorescence studies have failed to demonstrate a direct role for such an immunoglobulin. Only two other cases of biopsy-proven pretibial myxedema in a euthyroid patient were found in the literature.

Topical triiodothyronine stimulates epidermal proliferation, dermal thickening, and hair growth in mice and rats

The skin is a classic target tissue for thyroid hormone action. Although the histology of skin in hypothyroid states is well documented, the literature contains little assessment of skin in thyrotoxic states. In light of the paucity of information on skin under the influence of excess thyroid hormone, we investigated the direct effect of thyroid hormone on skin. Triiodothyronine (T3) was applied topically daily in liposomes to SKH-1 hairless mice for 7 days and to CD rats for 2 weeks. There was a dose-dependent increase in epidermal proliferation, dermal thickening, and hair growth in T3-treated animals. Mice that received 3.8 microg of T3 had 42% more hairs per millimeter than controls (p < 0.01), hair length that was 1,180% longer (p < 0.001), 49% greater epidermal 3H-thymidine incorporation (p < 0.01), and 80% more 5-bromo-2'-deoxyuridine (BrdU) stained cells (p < 0.05). Rats receiving 12.8 microg T3 had 48% greater dermal thickness than controls (p < 0.001), 26% greater epidermal thickness (p < 0.001), 85% more hairs per millimeter (p < 0.005), and 130% greater 3H-thymidine incorporation into the epidermis (p < 0.01). Thus, topically applied thyroid hormone has dramatic effects on both skin and hair growth. These observations offer a new strategy for developing thyroid hormone and its analogues for treating disorders of skin and hair growth.

Graves' disease presenting as localized myxedema in a thigh donor graft site

Pretibial myxedema, exophthalmus, and thyroid acropachy are the classic manifestations of Graves' Disease. However, myxedema in Graves' Disease can occur in locations other than the pretibial surfaces. Furthermore, with systemic symptoms, localized myxedema may occur at sites of trauma or scarring. We describe a patient with localized myxedema on the thigh at the site of a donor skin graft as the initial presentation of Graves' Disease.

Orbital decompression in Graves' ophthalmopathy associated with pretibial myxedema

Pretibial myxedema (thyroid dermopathy), an uncommon autoimmune manifestation of Graves' disease, is almost always associated with significant ophthalmopathy and may be a marker for an unusually prolonged or different course for the ophthalmopathy. However, it is not known if the response to therapy for eye disease is different in patients with pretibial myxedema. We compared the results of orbital decompression in 385 patients without and 52 patients with pretibial myxedema operated on between 1969 and 1989. Preoperative and postoperative characteristics of severe Graves' ophthalmopathy did not differ in patients with or without pretibial myxedema except for slightly, but not significantly, more proptosis and diplopia in the pretibial myxedema group. In response to a 1989-1990 questionnaire (83% response rate, n = 364), 89.1% without (n = 319) and 88.9% with (n = 45) pretibial myxedema reported satisfactory or acceptable appearance of the eyes. Self-assessment of visual acuity, eye comfort, diplopia, and overall rate of satisfaction with the status of the eyes did not differ between the groups. The presence of pretibial myxedema does not herald an unsatisfactory response to transantral orbital decompression.

Localized myxedema on the nasal dorsum in a patient with Graves' disease: report of a case

We report the case of a 56-year-old Japanese female with Graves' disease associated with localized myxedema on the nasal dorsum. The patient developed localized myxedema concomitantly with hyperthyroidism before antithyroid therapy was given. The lesion was totally removed surgically, as it was small and well circumscribed. Although unusual locations of localized myxedema have been reported elsewhere, there is to date no case of localized myxedema on the nasal dorsum without involvement of the pretibial area reported in the literature. We discuss this unique feature of our patient.

Endocrine-skin interactions. Cutaneous manifestations of pituitary disease, thyroid disease, calcium disorders, and diabetes

Endocrinologic disorders occasionally manifest themselves by their associated or induced cutaneous abnormalities. In some instances the initial and most prominent complaints of the patient are related to alterations in the skin, and thus the dermatologist will at times be the first physician consulted. In this article we describe the cutaneous lesions that occur in patients with acromegaly, hypopituitarism, hypothyroidism, hyperthyroidism, diabetes mellitus, glucagonomas, hypercalcemia, hypoparathyroidism, and fibrous dysplasia. In addition, we also discuss the role of the skin in vitamin D metabolism. Whenever possible and where known, we have attempted to point out the pathophysiologic mechanisms that account for the cutaneous changes.

Hyperthyroidism with periodic paralysis, acropachy, pre-tibial myxoedema, transient atrial fibrillation and myopathy

A case of thyrotoxicosis presenting with periodic paralysis and later complicated by acropachy, pretibial myxoedema and transient atrial fibrillation is described. This association has not been reported previously. Possible aetiological links are discussed.

Thyrotoxic pretibial myxoedema in Asian patients in Singapore

Over a 5-year period, three cases of thyrotoxic pretibial myxoedema were encountered. The incidence of pretibial myxoedema in Chinese thyrotoxic patients in Singapore was 0·7% (0·3% in females and 1·6% in males). One of the three patients also had thyroid acropachy. The incidence of thyrotoxic pretibial myxoedema in Singapore is compared with that in the literature and the aetiology briefly reviewed.