Dietary Modulation of Urinary MCP-1 in ADPKD

Inclusion Criteria:

1. Age ≥18
2. Diagnosis of ADPKD based on established clinical or genetic criteria (PKD 1/PKD2)
3. Estimated glomerular filtration rate (eGFR) between 45 and 90 mL/min/1.73 m²
4. Mayo Imaging Classification class 1C-1E based on MRI-derived height-adjusted total kidney volume.
5. Stable kidney function, defined as no acute kidney injury and no decline in eGFR >20% within the preceding 3 months
6. Stable antihypertensive and chronic medications for at least 4 weeks prior to enrollment
7. Ability and willingness to adhere to the prescribed dietary intervention
8. Ability to provide written informed consent

Exclusion Criteria:

1. eGFR <45 mL/min/1.73 m² or requirement for dialysis
2. History of kidney transplantation
3. Significant albuminuria, defined as urine albumin to creatinine ratio (UACR) >300 mg/g
4. Poorly controlled or unstable diabetes mellitus (e.g., HbA1c >8% or clinically significant glycemic variability or frequent hypoglycemia)
5. Use of Tolvaptan at the time of screening or within the study period
6. Current adherence to a ketogenic or carbohydrate restricted diet
7. Unintentional weight loss >5% within the preceding 3 months
8. Active infection, inflammatory disease, or malignancy that may influence inflammatory markers
9. Current use of systemic corticosteroids or immunosuppressive therapy
10. Active or symptomatic nephrolithiasis
11. Serum bicarbonate <20 mmol/L
12. Pregnancy or breastfeeding
13. Known eating disorder or condition limiting adherence to dietary interventions
14. Participation in another interventional study within the previous 3 months
15. Any condition that, in the opinion of the investigators, would interfere with study participation or interpretation of results