Metabolic Kidney Disease: A New Concept in the Interaction Between Obesity, Prediabetes, Diabetes and Liver Dysfunction.

Metabolic abnormalities such as obesity, insulin resistance, prediabetes, type 2 diabetes and metabolic dysfunction-associated steatotic liver disease (MASLD) increasingly contribute to chronic kidney disease (CKD). Although often treated as separate entities, these conditions share common mechanisms - including glomerular hyperfiltration, adipokine imbalance, chronic low-grade inflammation, endothelial dysfunction and lipid accumulation - that initiate and sustain renal injury long before classical CKD becomes clinically evident. The concept of Metabolic Kidney Disease (MKD) offers a unified framework that captures the continuum of renal involvement across the metabolic spectrum. Obesity- and prediabetes-related MKD frequently precede diabetic kidney disease, while MASLD - according to updated EASL-EASD-EASO guidelines - is a multisystem disorder with direct renal consequences. Mixed metabolic phenotypes further intensify metabolic stress, accelerating progression toward CKD. Recognising MKD has important clinical implications. Expanded screening strategies may identify early renal alterations in individuals with metabolic vulnerability who are not targeted by traditional CKD criteria. Integrating metabolic evaluation into nephrology practice may facilitate earlier, more holistic interventions and ultimately improve cardio-renal outcomes.