Differential diagnosis of rheumatoid granuloma

Abstract

Rheumatoid granuloma (RG) is histomorphologically defined as a subcutaneous palisading granuloma with central fibrinoid necrosis. Clinically, it presents as a nodule typically localized at pressure points near the joints. From the rheumatic pathological point of view, the main diagnostic challenge is the differentiation of RG from granuloma anulare, especially if clinical information on the site of removal, known diseases, duration of illness, medication and existing American College of Rheumatology (ACR) criteria are missing. Other granulomatous lesions, such as mycobacterial infections, foreign body granulomas, necrobiosis lipoidica or sarcoidosis, can be differentiated from RG by histopathological criteria or by additional examinations such as pathogen specification or PCR. An immunohistochemical marker for the differential diagnosis of granulomas is not yet available. Diagnosis is based on conventional H-E staining, alcian blue-PAS staining, polarizing analysis or PCR. In the following article, the most important granulomatous entities in the differential diagnosis of RG are introduced and the main diagnostic characteristics are discussed.

Myeloid Phenotypes in Tracheostomy‐Associated Granulation Tissue

“…Granulation tissue has been extensively studied in the context of inflammatory diseases such as rheumatoid arthritis, 15 tuberculosis, 16 and sarcoidosis, 17 but less is known about granulation tissue that occurs in patients with a tracheostomy. In sarcoidosis, monocytes and macrophages play a key role in granuloma formation.…”