Introduction: Dercum's disease is a rare disorder characterized by multiple painful subcutaneous lipomas on the trunk and extremities. The typical patient is an obese woman between 40 and 60 years of age with pain that appears out of proportion to physical finding. The pain associated with this condition is postulated to arise from enlarging lipomas producing pressure on peripheral nerves thereby initiating pain and sometimes parasthesias. This neuropathic pain is challenging to treat, typically unresponsive to conventional treatment including analgesics, adjuvant medications, and surgery, current literature describes some efficacy with intravenous lidocaine in the form of case reports. Unfortunately, this therapy has multiple potential side effects and is best administered at a tertiary care facility with significant experience in this treatment modality. Here we report a case of painful Dercum's disease responsive to transdermal Lidocaine.

Case Report: 61 y.o. female with medical history of Dercum's, PSVT, rheumatoid arthritis, depression, and migraine headaches. Medications included Verapamil, Pamelor, Imitrex, and Estring as well as Gabapentin 600mg three times daily for a prolonged time period. The patient's complaints included right posteromedial thigh and right anterior chest wall pain. The pain was initially rated as an 8/10. Physical examination revealed lipomas at the right anterior chest wall and right posteromedial thigh. Lidoderm® 5% transdermal patches were prescribed and placed over the two painful sites. At follow-up examinations at one month the patient rated their pain as 3/10, describing a >60% reduction in pain, this pain reduction persisted at subsequent one-month follow-up intervals.

Conclusion: Current therapeutic options in the treatment of Dercum's have proven either ineffective or cumbersome. The use of transdermal lidocaine is a safe and non-invasive treatment modality that has been efficacious in alternate forms. The use of this medication might prove preferable to more invasive or risky treatment and warrants further investigation.