Rheumatologic emergencies in the emergency department: Recognition, red flags, and initial management

Rheumatologic emergencies are uncommon but potentially fatal conditions that may present in the emergency department (ED) with acute organ dysfunction. These disorders often mimic sepsis or other critical illnesses, leading to delayed diagnosis and treatment initiation. To provide emergency physicians with a practical, ED-focused overview of major rheumatologic emergencies, emphasizing early recognition, red flag features, diagnostic priorities, and initial management strategies. A narrative review was conducted using the PubMed, MEDLINE, and international guideline repositories. Priority was given to publications from 2019 to 2025, including evidence-based guidelines, systematic reviews, and key clinical studies relevant to the emergency care. This review highlights life-threatening rheumatologic emergencies commonly encountered in acute care settings, including severe systemic lupus erythematosus flares, pulmonary–renal syndromes, catastrophic antiphospholipid syndrome, scleroderma renal crisis, atlanto-axial instability in rheumatoid arthritis, giant cell arteritis, macrophage activation syndrome, and septic arthritis. Key clinical red flags, essential investigations, and emergency management principles are outlined for all conditions. Emphasis is placed on conditions in which early immunosuppressive or disease-specific therapy should not be delayed while awaiting confirmatory tests. Rheumatologic emergencies require a high index of suspicion in patients with unexplained or rapidly progressive organ dysfunction. Early recognition, prompt initiation of appropriate therapy, and multidisciplinary collaboration are essential to prevent irreversible complications and mortality. Familiarity with these conditions enables emergency physicians to perform timely, life-saving interventions.