Regarding rheumatoid ahritis, all of the following statements are true except-
Rheumatoid nodules occur almost exclusively in RF or ACPA positive patients, usually in extensor tendons . Theyare frequently asymptomatic but some may be complicated by ulceration and secondary infection . Ref Davidsons 23e p1023,1024
The cricoarytenoid joint may be involved
HLA-D4 and HLA-DR4 are positive in patients with seropositive rheumatoid ahritis
Subcutaneous nodules are more frequent in seronegative patients
Diffuse intestinal fibrosis and pneumonitis may occur
Immune system