Long-term clinical spectrum and circulating RAS evaluation of anephric patients undergoing hemodialysis: A report of four cases and literature review

Abstract

Introduction:Bilateral nephrectomy leads to a short-term reduction in blood pressure. This is mainly due to a sharp change in the circulating renin-angiotensin system (RAS), but data on the long-term outcomes of their clinical status and further changes in circulating RAS are rare.Materials and methods:We enrolled four Chinese patients who had both of their kidneys removed two (1), six (1) and eight (2) years prior to this study, respectively. Their clinical data were collected retrospectively and circulating RAS was evaluated by radioimmunoassay.Results:Hypotension after surgery occurred in two patients who suffered thrombosis of the arteriovenous fistula, but no life-threatening complications occurred. The average hemoglobin level was 103.3±12.3 g/l. Two patients without hemorrhage received intravenous erythropoietin (EPO) of 4500–8000 iu/week. Extremely low plasma renin activity (PRA) of 0.08±0.03 ng/ml (normal range 0.93–6.56 ng/ml) showed in the patients. Surprisingly, plasma angiotensin II concentration (71.37±8.28 pg/ml) and aldosterone level (0.17±0.02 ng/mlng/ml) were within the normal range.Conclusions:The four anephric individuals did not suffer life-threatening complications while their hypotension gradually subsided and their EPO dosage was relatively low. Although their PRA level was extremely low, they produced normal levels of angiotensin II and aldosterone in plasma, which indicates the kidney-independent mechanism of angiotensin II production likely compensated in the long term.

The Effect of FGF23 on Cardiac Hypertrophy Is Not Mediated by Systemic Renin-Angiotensin- Aldosterone System in Hemodialysis

“…Interestingly, the PRA-S levels were reported to be even lower in anephric patients while AngII and aldosterone levels were within the normal range as reported by Liu et al ( 39 ). A trial by Wilkes et al ( 40 ) reported almost undetectable renin levels and suppressed AngII in anephric patients which were uninfluenced by volume reduction through hemodialysis treatment.…”

Shift from severe hypotension to salt-dependent hypertension in a child with autosomal recessive polycystic kidney disease after bilateral nephrectomies: a case report

“…Both, bilateral nephrectomies and PD itself are associated with increased risk of severe hypotension [ 3 ]. Hypotension has been described in children undergoing bilateral nephrectomies for Denys-Drash syndrome [ 3 ], congenital nephrotic syndrome [ 4 , 8 ], ARPKD [ 9 , 10 ], neoplastic diseases (epithelioma, bladder carcinoma) and hydronephrosis [ 9 ]. The data regarding the course of and risk factors of post-nephrectomy hypotension is limited.…”

“…The mechanisms of post-nephrectomy short-term hypotension are not fully elucidated but mainly relate to impairment of the circulating renin-angiotensin system (RAS) [ 9 ]. However, further research on long-term post-nephrectomy changes in circulating RAS is clearly needed.…”

“…These results suggest kidney and plasma renin independent production of angiotensin-II. For instance, the vascular system, adipose tissue, the brain and adrenal glands have been suggested as potential alternative sites of extrarenal RAS components production [ 9 ].…”

Refractory hypotension in an anephric patient: Immediate response to renal transplantation

“…The mechanism of this hypotension has not been fully elucidated, though alterations in the renin-angiotensin axis and endogenous vasoactive mediators are thought to play a central role. In a longitudinal case series, Liu, et al evaluated the circulating renin-angiotensin system (RAS) of four anephric patients using serial radioimmunoassay [7]. Two patients became hypotensive following nephrectomy; one recovered after six years, the other had not recovered at publication.…”