Secondary hyperhidrosis—excessive sweating triggered by underlying systemic medical conditions or hormonal imbalances—can sometimes be associated with autoimmune disorders that disrupt the body's autonomic temperature regulation or cause hyperthyroidism, such as Graves' disease. Additionally, systemic inflammatory conditions like systemic lupus erythematosus and rheumatoid arthritis can induce severe internal hot flashes, night sweats, and localized thermal dysregulation, though primary focal hyperhidrosis is typically a distinct neurological condition unrelated to classic autoimmune markers.