Palmar granuloma annulare, though rare, can be difficult to treat with traditional methods, but doctors report a successful outcome with the use of dapsone in treating a 72-year-old woman with the condition.
National report - Dermatologists may be used to seeing granuloma annulare in children, where the idiopathic inflammatory condition typically resolves on its own. But, less commonly, the condition can show up in older patients, causing discomfort and significant pain, especially if lesions are on the palms or soles of the feet.
In such cases, known effective treatments are limited, but researchers describe a successful outcome in treating a 72-year-old woman's granuloma annulare with oral dapsone.
"This was somewhat of a rare variant of granuloma annulare," according to David Butler, M.D., director, division of dermatology, Scott & White Hospital and Texas A&M University System Health Science Center College of Medicine, Temple, Texas.
Oral dapsone has been shown to be effective in the treatment of granuloma annulare in more typical locations in the past, and the patient was treated with dapsone at an initial dose of 50 mg daily. After a month of therapy, the patient reported moderate improvement and the dapsone dosage was increased to 100 mg daily, along with 800 units of vitamin E daily. Vitamin E reduces the risk of anemia due to hemolysis caused by dapsone.
The patient showed dramatic improvement after three months of therapy, and therapy was continued at 100 mg daily. At six-month follow-up, no clinically apparent lesions were seen, and the dapsone was tapered to 75 mg daily. No recurrence of the granuloma annulare has been noted.
"Other treatments to consider include intralesional triamcinolone, oral nicotinamide and oral antimalarials," Dr. Butler says. "However, intralesional corticosteroids are very painful for treatment of the palms and soles, so it's nice to have an oral medicine to improve this that is fairly safe."
Mechanism of action
Dapsone's mechanism of action in the treatment of granuloma annulare is unclear, but it is known to have profound anti-inflammatory effects on neutrophils and possibly other types of inflammatory cells, the researchers report.
Dr. Butler's patient tolerated the therapy well and had no clinical adverse effects, but Dr. Butler notes that in the older age group, dapsone can cause methemoglobinemia anemia, hemolytic anemia and, in rare cases, allergies, so patients should be monitored for those concerns.DT
Disclosure: Dr. Butler reports no conflicts of interest related to this article.