Using the Blanch Sign to Differentiate Weathering Nodules From Auricular Tophaceous Gout

To the Editor:

We commend the recent report by Smith et al (Cutis. 2016;97:166, 175-176) that described multiple white nodules on the bilateral helical rims of the ears in a 40-year-old man, which was determined to be bilateral auricular tophaceous gout. Furthermore, we appreciate the inclusion of weathering nodules in the differential diagnosis and wish to share our experience with these lesions.

Auricular tophaceous gout and weathering nodules are clinically similar. Weathering nodules may appear as single or multiple, 2 to 3 mm in diameter and 1 to 2 mm in height, white to flesh-colored papules usually found on the helical rim of the ear (Figure 1).¹ We recently described 10 patients with weathering nodules and their associated risk factors.² We observed that the weathering nodules will blanch upon the application of pressure to the adjacent helical rim; a positive “blanch sign” may be used to differentiate weathering nodules from auricular tophaceous gout and other lesions of the ear (Figure 2). Furthermore, patients with weathering nodules typically exhibit a history of sun exposure and often have other cutaneous findings such as actinic keratoses. The pathogenesis of weathering nodules was previously thought to rely solely on actinic damage; however, we reported a pediatric case of weathering nodules that presented following radiotherapy to the ears.²

Figure 1. Pronounced weathering nodules on the helix and antihelix of the right ear of a male surfer who had been exposed to ionizing radiation at 4 years of age.

Figure 2. A 56-year-old man who is a mail carrier on immune suppressive agents with camouflaged lesions (A) that became clearly distinguishable as the lesions blanched when pressure was applied to the ear (B).

In summary, weathering nodules should be included in the differential diagnosis of auricular tophaceous gout. In addition, a positive blanch sign may be a useful clinical tool in differentiating weathering nodules from other ear lesions.