Systemic diseases is the academic and research field dedicated to the study of pathologies that affect multiple organ systems or the entire body, rather than being confined to a single localized site. This concept investigates the complex etiologies, interconnected pathophysiological mechanisms, and diverse clinical manifestations of conditions characterized by widespread systemic involvement. Key characteristics include the analysis of multi-organ dysfunction, the identification of systemic inflammatory or immunological processes, and the development of integrated diagnostic and therapeutic strategies. Its significance lies in advancing the understanding of complex, chronic, and often debilitating conditions that require a holistic approach to medical research and clinical management.