Clinical Approach to Periodic Inflammation of Unknown Origin in Adults, with a Focus on the Diagnosis of Systemic Autoinflammatory Diseases

Abstract

In most of these unknown cases, it's not that I'm completely lost. I know in a general sense that there is an inflammatory disease present. I know that there doesn't appear to be cancer in the background, or infection. I have a lengthy list of conditions that the patient does not have. But one of my most difficult tasks when I sit down with a patient at a follow-visit is to take a deep breath, adjust my glasses and admit that I don't know what's wrong." Charles Radis. The rheumatologist as detective. The Rheumatologist, 1 Feb 2015. Patients with periodic inflammation who remain undiagnosed after initial rational and targeted investigation pose a clinical conundrum. This editorial presents an approach to these cases and focuses on the recognition and diagnosis of systemic autoinflammatory diseases (SAIDs). This approach utilises genetic testing for SAIDs, recognising the presentations of non-genetic SAIDs, and empiric trials of therapy in suspected inflammatory disease. Ultimately, not achieving a final diagnosis is very common and the clinician's role is to help manage the uncertainty around this through support, follow-up and reassurance. This editorial outlines a clinical approach to patients with periodic inflammation of unknown origin despite initial rational and targeted investigation. The focus of the editorial is on the recognition and diagnosis of systemic autoinflammatory diseases (SAIDs). Although rare, SAIDs are valuable diagnoses given they carry a risk of disease-associated damage and are often treatable. The authors are from a subspecialty clinic in London, UK, which is the national referral centre for adult SAIDs. The basis of this approach is both a review of the literature and our experience from our fever clinic to which patients are referred for the consideration of a SAID diagnosis in the setting of periodic fever and inflammation.