Serum Aldosterone Levels in the Patients with Chronic Kidney Disease of Uncertain Etiology

Abstract

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 obvious in some categories of Chronic Kidney Disease (CKD) like tubular interstitial diseases. The beneficial effects of RAAS blockers are controversial if RAAS is 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 in the renal clinic of the divisional hospital, Girandurukotte. The basic biochemical parameters like serum Aldosterone, Angiotensin II, creatinine, serum electrolytes, and osmolality were measured by using serum and urine samples of the participants. Statistical analysis was performed by using SPSS software version 23. Only 4.4% and 6.7% of the study participants had increased serum Aldosterone and serum Angiotensin II levels respectively. 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 significantly negatively correlated with eGFR (r=-0.353, p<0.01). Moreover, serum aldosterone had a significant elevation (p=0.024) in the late stages of the disease than early stages and also was significantly associated with proteinuria (p=0.032). This study indicated that there were no obvious features of activated RAAS in CKDu with lower than the upper limit of the normal levels of serum Aldosterone levels in more than 95% of the patients. Serum Aldosterone could be a competitive biomarker to confirm the activated RAAS in some groups of CKD with a higher risk of acquiring prerenal Acute Kidney Injury (AKI) due to RAAS blockade.