**4. Conclusions**

The impact of obesity on the kidney has received attention after the recognition that BMI is the second most important marker in developing ESKD after proteinuria and one of the most relevant associated with the presence of CKD, since obesity is frequently associated with hypertension, metabolic syndrome, and diabetes. An important impact on subjects with renal replacement therapy and renal transplantation is also present. The pathologic lesions included a characteristic glomerulopathy coupled with cellular fat load and perivascular fat deposit as well as so-called fatty kidney with fat deposits in the perirenal and renal sinus. The mechanisms linking obesity and renal damage are well understood, including several effector mechanisms with interconnected pathways. In the presence of an increment in urinary albumin excretion, it is mandatory to take action in order to reduce overweight and to control hypertension, diabetes, and dyslipidemia to further prevent GFR reduction.

**Author Contributions:** Conceptualization, V.K. and J.R.; methodology, V.K. and J.R.; resources F.M. and C.T.; writing, V.K. and F.M.; review and editing, C.T., F.M., V.K. and J.R.; supervision, V.K. and J.R. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Acknowledgments:** The study was partially funded by CIBER Fisiopatología Obesidad y Nutrición (CB06/03), Instituto de Salud Carlos III, Spain; supported by grant numbers PI11/00144 and PI14/01781, Instituto de Salud Carlos III.

**Conflicts of Interest:** The authors declare no conflict of interest.
