Fibromyalgia with elevated rheumatoid factor is associated with poor therapeutic response but not with progression to rheumatoid arthritis. Prospective cohort study Freddy Liñán Ponce; Juan Leiva Goicochea; David Sevilla Rodríguez; Elmer Hidalgo Bravo; Ginna Obregón Atanacio; Inés Loyola Macalapú; Paola Jáuregui Rojas; Jackeline Yampufe Canani;

Ultrasound tenosynovitis: A differential feature of patients with seronegative rheumatoid arthritis Santiago Ruta; Einer Sanchez Prado; Facundo Salvatori; Juan Arguello; Darío Aguerre; Sebastián Magri; Rodrigo García Salinas;

Rotator cuff tendinopathy is associated with increased activity score in rheumatoid arthritis Jorge Medina-Castillo; Rodrigo J. Castillo-de la Garza; David Vega-Morales; Jorge A. Esquivel-Valerio; Axel A. De León-Pérez; Lorenia De La Cruz-Becerra; Alondra Elizabeth Montoya-Montes; Lourdes Gil-Flores; Dionicio Ángel Galarza-Delgado;