Aseptic Neutrophilic Cutaneous Abscesses Associated with Rheumatoid Arthritis: A Case Report

Abstract

Aims: We report a case of exclusively cutaneous aseptic neutrophilic abscesses occurring in a patient with rheumatoid arthritis and discuss the diagnostic and therapeutic features of this rare and under-recognised neutrophilic dermatosis. Presentation of Case: A 64-year-old woman with a 5-year history of rheumatoid arthritis treated with non-steroidal anti-inflammatory drugs presented with a 3-year history of recurrent, painless, bilateral fistulised nodules on the lower limbs, buttocks, and feet, associated with unquantified fever. Laboratory investigations showed neutrophilic leucocytosis and elevated C-reactive protein. Bacteriological, parasitological, and mycobacterial cultures were negative, and histology revealed abundant altered neutrophils on a necrotic background without granulomas. Oral antibiotics and antifungal therapy failed to induce improvement, and abdominal ultrasound excluded visceral abscesses. Discussion: The diagnosis of aseptic neutrophilic abscesses was established based on the clinical presentation, negative microbiological work-up, histopathological findings, and the context of rheumatoid arthritis. Systemic corticosteroids at 0.5 mg/kg/day produced marked improvement within two weeks and complete resolution after six weeks. This entity represents the deepest anatomo-clinical form of neutrophilic dermatosis and is most frequently linked to inflammatory bowel disease, although rheumatic, haematological, and malignant associations are also described; purely cutaneous presentations, as observed here, remain uncommon. Conclusion: Aseptic neutrophilic abscesses should be considered in patients with sterile, antibiotic-resistant fistulised nodules, particularly in the setting of rheumatoid arthritis. Systematic screening for inflammatory bowel disease and visceral involvement is warranted to exclude the potentially severe aseptic abscess syndrome.