Localized myxedema in Grave's disease confined to the toes

[Graves' dermopathy on the big toe]

BACKGROUND

Localized myxoedema is a rare dermopathy in patients with Graves' disease. The pretibial area is the most commonly affected region but herein we present a case of myxoedema of the big toe.

PATIENTS AND METHODS

A 44-year-old male with Graves' disease ongoing for seven years presented bilateral ophthalmopathy and myxoedema of the big toes. The myxoedema was treated successfully with intralesional steroids.

DISCUSSION

The physiopathology of myxoedema involves fibroblast activation and glycosaminoglycan production. This activation could result from stimulation of TSH receptors at their surface by TSH receptor antibodies (TRAK) or from an inflammatory process. The pretibial topography may be related to the high frequency in this area of microtrauma, with modulation of the cytokine microenvironment.

CONCLUSION

The atypical localization seems to correlate with a Koebner phenomenon. Treatment of Graves' disease is generally insufficient to resolve the cutaneous problems. Topical corticosteroid therapy generally results in rapid improvement of recent lesions.

Nodular mucinosis in Graves disease mimicking gouty tophi

We report a patient who had Graves disease and recently developed subcutaneous nodules over both lower limbs. Initially, gouty tophi were suspected by the endocrinologist so he was referred to the rheumatology clinic. However, a series of studies, including soft tissue ultrasonography, magnetic resonance image, and biopsy revealed nodular mucinosis resulting from Graves dermopathy. Nodular mucinosis is an unusual form of myxedema which mimics tophaceous gout, and should be considered in patients with Graves disease presenting with subcutaneous nodules.