Clinical management of rheumatologic conditions co-occurring with inflammatory bowel diseases.

Spondyloarthritis (SpA) is the most common extra-intestinal manifestation in patients with inflammatory bowel diseases (IBD). Articular disorders may also appear as 'paradoxical' effects during biologic therapy with anti-tumor necrosis factor (TNF). Areas covered: In this narrative review, we report the current knowledge about the pathogenesis, the diagnosis and the therapeutic management of articular diseases occurring in patients with IBD. Expert commentary: Evidence-based recommendations for the management of IBD-associated SpA and paradoxical arthritis are lacking. Then, collaboration between gastroenterologists and rheumatologists is mandatory to guarantee the best outcomes for these patients, from a prompt diagnosis to an appropriate therapeutic strategy. Among therapies currently available, steroids, sulfasalazine, methotrexate and anti-TNFs are recommended for both gastrointestinal and articular diseases, whereas non-steroidal anti-inflammatory drugs (NSAIDs) and etanercept are contraindicated in IBD. Thiopurines are not effective for the treatment of articular symptoms. Several agents have been recently introduced for the treatment of IBD, such as vedolizumab, a gut-selective anti-α4β7integrin, and ustekinumab, an anti-interleukin 12/23. Their effects on SpA still need to be clarified; however, the possible contemporary administration of biologics with different molecular targets is becoming an intriguing option to cover multiple inflammatory manifestations in the same patient and is worthy of further investigation.