Development of Inflammatory nodules after using a Microwave-
Now open: Certificate Course in Management of Covid-19 by Govt. Of Gujarat and PlexusMDKnow more...Now open: Certificate Course in Management of Covid-19 by Govt. Of Gujarat and PlexusMDKnow more...
Hidradenitis suppurativa (HS) is an inflammatory condition characterized by recurrent painful erythematous nodules developing most commonly in the axilla or groin. HS is a chronic condition culminating in scarring and often dermal sinus tracts. A microwave-based energy device is a noninvasive device for treatment of axillary hyperhidrosis. It uses microwave energy targeting apocrine and eccrine glands at the interface between the dermis and subcutis.

A 31-year-old man with no prior personal or family history of HS presented with recurrent erythematous painful nodules in both axillae after receiving treatment with microwave-based energy device for axillary hyperhidrosis. The patient was never a smoker and had no significant medical or surgical history. The patient first had nodules approximately 1 month after his first treatment. The nodules were occasionally suppurative and painful, and some healed with scarring.

The patient did not undergo further microwave-based energy treatments nor pursued treatment for the nodules. On presentation, a year and a half after undergoing microwave-based energy treatment, he continued to have nodules in his axillae, averaging 1 new nodule per month. A solitary tender erythematous nodule was noted on examination in the left axilla, measuring 1.5 × 1 cm. Both axillae showed scarring at sites of prior nodules. No sinus tract formation was noted.

Intralesional triamcinolone acetonide, 0.4 mL of 10 mg/mL was injected into the nodule with improvement on follow-up 1 month later. Development of inflammatory nodules in this case may be explained by the microwave-induced periglandular fibrosis and reactive inflammatory infiltrates leading to altered infundibular anatomy and function, similar to pathophysiology of HS. To our knowledge, this is the first reported case of chronic repetitive inflammatory nodules and scarring after microwave-based energy device treatment.