FIGURE 1.

Neuroimmune alterations and olfactory deficiencies promoted by chronic kidney disease. In chronic kidney disease (CKD), kidney function is compromised due to alterations of the glomerular filtration rate (GFR), as the disease progresses from stage G1 (≥90 ml/min/1.73 m²) to G5 (<15 ml/min/1.73 m²). This leads to increased levels of the uremic toxins indoxyl sulfate and p-Cresol. The toxin accumulation activates the immune system by releasing cytokines and increasing prolactin (PRL) levels due to inadequate GFR. CKD patients develop deficiencies in odor detection, identification, and discrimination that are reversible after renal transplantation. Additionally, olfactory alterations can cause malnutrition, worsening the patients’ condition. Evidence on the regulatory role of PRL in olfactory processing suggests an interaction between CKD-induced high PRL levels and the olfactory deficiencies (dotted blue arrows). Created with BioRender.com.