Systemic autoinflammatory disease diagnoses in a single year from a UK national referral centre

Abstract Objectives The diagnosis of systemic autoinflammatory diseases (SAIDs) is frequently missed or delayed. The establishment of specialist clinics and the availability of genetic testing enables increased diagnosis of these disorders. We aimed to study the case mix and demographics of patients referred to a UK national centre for primarily adult SAID. Methods The medical records of all new patients seen in 2022 were reviewed. Genetic testing either involved a next-generation sequencing (NGS) panel of 24 SAID-related genes, or Sanger sequencing of individual genes. Results Of 306 patients, 121 (39.5%) were diagnosed with SAID. Of the patients with SAID, 59% were male, 79% were new diagnoses, and 21% had transitioned from paediatric care. The new-diagnosis group were primarily adults and included patients with SAIDs with known late-adult onset. Fifty-nine of the patients with SAID (49%) had genetic results supportive of monogenic disease. The most frequent diagnoses were FMF (31%), idiopathic recurrent pericarditis (14%), and undifferentiated SAID (11%). The median age at diagnosis was 7 years [interquartile range (IQR) 3.75–12.5] for transition patients, 35 years (IQR 22–45.75) for newly diagnosed patients, and 65 years (IQR 57.75–74.25) for newly diagnosed late-adult-onset SAIDs. The median diagnostic delay was 2 years (IQR 0–5.5) in transition SAID, 4.5 years (IQR 1–12.75) in new diagnoses, and 6 years (IQR 2–8.5) in late-onset SAID. Conclusion The clinic sees a clinically important number and range of SAID diagnoses in a primarily adult population. SAID diagnosis remains challenging, and it was found that there were significant diagnostic delays.