RGD is found in association with various systemic diseases, such as autoimmune diseases (eg, inflammatory arthritis, connective tissue disease, vasculitis),1, -3 malignancy (especially hematologic neoplasms),4 certain drugs [eg, tumor necrosis factor (TNF) inhibitors, furosemide, angiotensin-converting enzyme inhibitors],1,5 and rare infections (coccidioidomycosis and borreliosis).6,7 The majority of patients had a systemic association prior to diagnosis.2 However, it is unclear which investigations should be carried out and if new associations were subsequently identified. This evidence concerns the gene TNF and infection.