An Unprecedented Triad: Simultaneous Acute Pancreatitis, Axonal Polyneuropathy, and Type 1 Diabetes Mellitus in a Catastrophic Juvenile Lupus Flare.

A 14-year-old female with juvenile systemic lupus erythematosus (jSLE) presented with a life-threatening and previously unreported triad: the simultaneous onset of acute pancreatitis, severe axonal polyneuropathy, and autoimmune Type 1 Diabetes (T1D). This catastrophic, polysyndromic flare was driven by a hyperinflammatory state consistent with Macrophage Activation Syndrome, with the T1D diagnosis confirmed by high-titer GADA, IA-2A, and ZnT8A autoantibodies. This case provides a rare clinical model of a "perfect storm" in which a systemic inflammatory crisis appears to have inflicted widespread vasculitic injury while simultaneously acting as a "second hit" to trigger a latent, organ-specific autoimmunity. Aggressive immunosuppression with pulse corticosteroids and mycophenolate mofetil led to remission of this multi-fronted immunological attack. This case expands the phenotypic spectrum of jSLE to include a new paradigm of "lupus crisis," demonstrating that a single flare can catastrophically shatter the boundaries between systemic and organ-specific autoimmune diseases. It mandates a high index of suspicion for concurrent, multi-lineage autoimmunity in patients presenting with severe, hyperinflammatory jSLE.