ABSTRACT
Reactive arthropathies can be defined as a sterile inflammatory arthropathy temporally associated with a remote antigenic exposure. While this antigenic exposure is usually infectious, in conditions like serum sickness, a similar reactive inflammatory arthropathy can occur to noninfectious agents such as a medication. One of the challenges in writing about these conditions is the diversity in terminology that has been used in the past to describe these conditions. Several of these conditions have been labeled in alternative ways and presently could be better classified as forms of juvenile idiopathic arthritis (JIA). Examples of this include juvenile psoriatic arthritis and enthesitis-related arthritis which are subtypes of JIA in the ILAR classification system (see below). Unfortunately, much of the literature describing these conditions predates these criteria, and so the previous framework for describing these conditions is used in this chapter. An example of this approach is shown in the next section on the broad category of juvenile spondyloarthropathy.
