Riziform bodies are structures in the synovial fluid or attached to the synovium, which macroscopically resemble rice grains. They are common in patients with rheumatoid arthritis and result from a chronic inflammation. They are found in 25% of aspiration procedures or joint surgery. However, there are still no publications reporting its presence in the subcutaneous tissue. We report for the first time the occurrence of riziform bodies in the subcutaneous plane of the palmar region in a patient with rheumatoid arthritis, confirmed by sonographic and anatomopathological examination, successfully treated with surgical drainage, without recurrences after two years of follow-up.

Keywords: Abscess; Rheumatoid arthritis; Dermatopathies; Hand dermatoses; Outpatient Surgical Procedures; Surgical Diagnostic Techniques

BACKGROUND: Pyoderma gangrenosum is a rare neutrophilic dermatosis with very low incidence and varied clinical presentation associated with different comorbidities. It is also a diagnostic-therapeutic challenge.
CLINICAL CASE: A 79-year-old woman presented 18 months of dermatosis evolution that began as a perianal pustule and progressed to a 20 cm in diameter ulcer. Due to her comorbidities, she received topic treatment with satisfactory evolution.
CONCLUSIONS: Pyoderma gangrenosum is frequently associated with a systemic disease. Consequently, it must be approached from a systemic perspective with the support of a multidisciplinary team to provide the most appropriate treatment.

Keywords: Pyoderma gangrenosum, Skin diseases, Peptic ulcer hemorrhage, Hypothyroidism