Serum Aldosterone in patients with Chronic Kidney Disease of uncertain etiology in Girandurukotte and Wilgamuwa, Sri Lanka

The Renin Angiotensin Aldosterone System (RAAS) is the main regulator of body fluid and electrolyte balance in the human body. Features of RAAS activation, such as hypertension and fluid retention, are not apparent in some categories of CKD-like tubular interstitial diseases. The beneficial effects of RAAS blockers are controversial if not activated.  This study was conducted to identify the features of RAAS activation in CKDu and to evaluate the representativeness of Aldosterone as a marker of activation. A cross-sectional study was conducted on 119 definite CKDu patients at the renal clinics in Girandurukotte and Wilgamuwa, Sri Lanka. The basic biochemical parameters, serum electrolytes, and osmolality were measured by using serum and urine samples of the participants. Statistical analysis was performed in IBM SPSS statistics version 23. Only 4.4% and 6.7% of study subjects had increased serum Aldosterone and serum Angiotensin II. There was a significant positive correlation between serum Aldosterone with serum creatinine (r=0.477, p<0.01) and Angiotensin II (r=0.379, p<0.01). Inversely, it was negatively correlated with eGFR (r=-0.353, p<0.01). Moreover, serum aldosterone had a significant elevation in the late stages (p=0.024) than early stages and was significantly associated with proteinuria (p=0.032).  Results showed no indications of activated RAAS in patients with the diagnosis of definite CKDu. A significant number of the population had hypernatremia which is positively correlated with hyperosmolality, indicating dehydration.  The possibility of subclinical dehydration that may have an effect with faster progression.