Predictors of long-term prognosis in acute kidney injury survivors who require continuous renal replacement therapy after cardiovascular surgery.

The long-term prognosis of patients with postoperative acute kidney injury (AKI) requiring continuous renal replacement therapy (CRRT) after cardiovascular surgery is unclear. We aimed to investigate long-term renal outcomes and survival in these patients to determine the risk factors for negative outcomes. Long-term prognosis was examined in 144 hospital survivors. All patients were independent and on renal replacement therapy at hospital discharge. The median age at operation was 72.0 years, and the median pre-operative estimated glomerular filtration rate (eGFR) was 39.5 mL/min/1.73 m2. The median follow-up duration was 1075 days. The endpoints were death, chronic maintenance dialysis dependence, and a composite of death and chronic dialysis. Predictors for death and dialysis were evaluated using Fine and Gray's competing risk analysis. The cumulative incidence of death was 34.9%, and the chronic dialysis rate was 13.3% during the observation period. In the multivariate proportional hazards analysis, eGFR <30 mL/min/1.73 m2 at discharge was associated with the composite endpoint of death and dialysis [hazard ratio (HR), 2.1; 95% confidence interval (CI), 1.1-3.8; P = 0.02]. Hypertension (HR 8.7, 95% CI, 2.2-35.4; P = 0.002) and eGFR <30 mL/min/1.73 m2 at discharge (HR 26.4, 95% CI, 2.6-267.1; P = 0.006) were associated with dialysis. Advanced age (≥75 years) was predictive of death. Patients with severe CRRT-requiring AKI after cardiovascular surgery have increased risks of chronic dialysis and death. Patients with eGFR <30 mL/min/1.73 m2 at discharge should be monitored especially carefully by nephrologists due to the risk of chronic dialysis and death.

Calcium channel blockers suppress daily variations of blood pressure in hypertensive patients with end-stage renal diseases.

Hypertension is a well-known cardiovascular risk. Patients with end-stage renal diseases frequently suffer hypertension. Furthermore, daily variations of blood pressure are relatively large in patients treated with hemodialysis, partly due to ultrafiltration. Twenty hypertensive patients with end-stage renal diseases whose blood pressure was controlled by a single antihypertensive agent, either angiotensin receptor antagonist (ARB) or calcium channel blocker (CCB), were enrolled into the study. Home blood pressure measurements were also performed. Average systolic and diastolic blood pressures were similar between two agents. However, variations of systolic blood pressure during ARB treatment were greater than those of CCB, and maximal differences in daily systolic blood pressure during treatment with ARB (19±7 mmHg) were greater than those with CCB (14±6 mmHg, p<0.01). Systolic blood pressure measured after hemodialysis under ARB therapy (110±6 mmHg) was lower than that of CCB (118±6 mmHg, p<0.05). Daily variations of diastolic blood pressure were similar between ARB and CCB periods. Our results indicate that variations of systolic blood pressure during ARB treatment are larger than CCB, and suggest that CCB is useful to obtain the better quality of blood pressure control, improving blood pressure stability by preventing substantial drops in blood pressure in hypertensive patients with end-stage renal diseases.

Aliskiren reduces morning blood pressure in hypertensive patients with diabetic nephropathy on hemodialysis.

Our previous study indicated that the exchange from an angiotensin receptor blocker (ARB) to aliskiren reduced morning blood pressure and albuminuria in hypertensive patients with diabetic nephropathy. We extended the above study and assessed the effects of exchanging from an ARB to aliskiren on home blood pressure in hypertensive patients with diabetic nephropathy on chronic hemodialysis. The patients who were persistently hypertensive despite antihypertensive therapy, including ARB, were considered as candidates for the exchange from the ARB to aliskiren. Patients' age and durations of diabetes and hemodialysis were averaged as 62 ± 9 years old, 15 ± 8 and 7 ± 3 years, respectively. Aliskiren decreased morning systolic blood pressure (149 ± 14 to 144 ± 13 mm Hg, n = 30, P < .01) and plasma renin activity (3.5 ± 1.1 to 1.2 ± 0.6 ng/mL/h, P < .01) without changes in serum potassium. Aliskiren also reduced interdialytic weight gain (2.7 ± 0.6 to 2.5 ± 0.5 kg/interval, P < .05) and attenuated the magnitude of intradialytic declines in systolic (-20 ± 11 to -17 ± 10 mm Hg, P < .05) and diastolic blood pressure (-9 ± 6 to -5 ± 5 mm Hg, P < .01). The exchange from an ARB to aliskiren is safe and useful to control home blood pressure in hypertensive hemodialysis patients with diabetic nephropathy. Aliskiren reduced both intradialytic blood pressure drops and interdialytic weight gain in patients with DN.

Aliskiren reduces morning blood pressure in hypertensive patients with diabetic nephropathy.

Diabetic nephropathy (DN) is a leading disease that requires renal replacement therapy. The progression of renal dysfunction in DN is faster than the other renal diseases. While antihypertensive therapy reduces albuminuria, a good indicator for the progression, hypertension in DN is treatment resistant. Among patients with DN who took angiotensin receptor blockers (ARBs), 27 patients who exhibited poor control of albuminuria were enrolled into the study. Angiotensin receptor blocker was exchanged to aliskiren (150-300 mg/d) and clinical parameters were followed for 6 months. Exchange to aliskiren decreased albuminuria (1.57 ± 0.68 to 0.89 ± 0.45 g/gCr, P < .01) without changes in estimated glomerular filtration rate and office blood pressure (BP). Body weight and hemoglobin A1c were not altered. Aliskiren also reduced plasma renin activity (2.0 ± 0.9 to 1.2 ± 0.6 ng/mL/h, P < .01). While evening BP was unchanged, morning systolic BP (139 ± 8 to 132 ± 7 mm Hg, P < .01) and diastolic BP (81 ± 7 to 76 ± 6 mm Hg, P < .05) were decreased significantly after 6 months. Our results indicated that aliskiren decreased BP, especially morning BP in hypertensive patients with DN. The present data suggest that aliskiren exerts renoprotective actions including reduction in albumin excretion for patients with DN.

Long-term effects of calcium antagonists on augmentation index in hypertensive patients with chronic kidney disease: a randomized controlled study.

BACKGROUND: Our previous retrospective study showed that benidipine was superior to amlodipine (AM) for reducing proteinuria and preserving the augmentation index (AI) in patients with chronic kidney disease (CKD). METHODS: The present study enrolled CKD patients whose blood pressure was not well controlled by an angiotensin receptor blocker (ARB) and a calcium channel blocker other than AM or azelnidipine (AZ). Either AM (5 mg) or AZ (16 mg) was prescribed randomly. Clinical parameters, including proteinuria, serum creatinine, and AI, were measured before initiation of AM or AZ and 1 year later to assess the long-term effect on renal function and central blood pressure. RESULTS: Brachial and central blood pressures were similarly reduced in both groups. However, pulse rate increased in the AM group, but decreased in the AZ group (+3 ± 1 vs. -2 ± 1 bpm, p < 0.0001). The reduction of proteinuria was greater in the AZ group (-29 ± 2 vs. -38 ± 3%, p < 0.01). Improvement of AI adjusted for a pulse rate of 75 bpm was larger in the AZ group than in the AM group (-4 ± 1 vs. -9 ± 1%, p < 0.05). In both groups, estimated GFR remained unchanged throughout the observation period. CONCLUSION: In hypertensive patients with CKD, combined treatment with AZ and an ARB decreases proteinuria and preferentially improves arterial reflection.

Aging is an important risk factor for peritoneal dialysis-associated peritonitis.

Peritonitis remains a leading complication of peritoneal dialysis (PD). The aim of this observational retrospective cohort study, conducted at our single center, was to determine the risk factors for peritonitis. A Cox proportional hazards model was used for the multivariate analysis. The event investigated was peritonitis, and the variables studied were sex, age, diabetes mellitus, use of statins, and several laboratory values including albumin and total cholesterol. All PD patients who visited our clinic from January 2005 to September 2011 and who had complete medical records for at least 3 years were included. Among the 82 patients who met the criteria (mean period of observation: 1086 +/- 752 days; mean age: 62.0 +/- 12.3 years), 47 had experienced at least 1 episode of peritonitis. Aging was a significant risk factor for peritonitis, with a relative risk of 1.04 per year (p = 0.014). In our study, aging--rather than diabetes mellitus, efficiency of PD, or nutrition status--was an important risk factor for PD-associated peritonitis. Poor PD technique because of advanced age might be one of the reasons for this result.

Continuous ambulatory Peritoneal dialysis beyond a decade: cases from a single center.

A broad consensus has not been reached on the appropriate timing for cessation of peritoneal dialysis (PD). Decreasing urine volume, repeated and refractory peritonitis, and deterioration of the peritoneal membrane are major reasons to stop PD. Also, the link between length of time on PD and encapsulating peritoneal sclerosis (EPS) should be an additional concern. The aim of the present study was to investigate patients who had been on continuous ambulatory PD (CAPD) for a long time. All patients undergoing CAPD at our kidney center for more than a decade from January 1990 to September 2011 were included in the study. Among more than 436 CAPD patients, 11 met the inclusion criteria. Their mean PD duration was 12.3 +/- 3.1 years. Mean age at CAPD introduction had been 46.0 +/- 10.1 years. All patients had nondiabetic nephropathy as the underlying cause of their end-stage renal disease. At least 2 of the 11 had developed EPS, and 1 had subsequently died from EPS. Patients on prolonged CAPD for more than a decade are still rare. The CAPD modality may be continued if it is efficiently maintained within an acceptable level, but EPS remains a serious complication of prolonged PD.

Clinical presentation in patients more than 80 years of age at the start of peritoneal dialysis.

The age of new dialysis patients is rapidly increasing. In the present study, we examined clinical presentation in new peritoneal dialysis (PD) patients 80 years of age or older at our hospital. Data were collected from the records of patients newly starting continuous ambulatory PD (CAPD) therapy between January 2005 and July 2010. During that period, 11 patients 80 years of age or older (average age: 83.1 +/- 3.8 years) were introduced to PD therapy. The reason for dialysis was hypertensive nephrosclerosis in 8 patients, and chronic glomerulonephritis, chronic tubulointerstitial nephritis, and an unknown primary disease in 1 patient each; there were no cases of diabetic nephropathy. At dialysis start, average serum creatinine was 6.1 +/- 1.4 mg/dL, arterial wall calcification was found by computed tomography or chest radiography in 10 of 11 patients (90.9%), and aortic or mitral valve calcification, or both, was found by echocardiography in 3 patients (27.3%). By the end of January 2011, 8 patients had died. Average survival after the start of PD was 31.9 +/- 22.3 months. Hypertensive nephrosclerosis, a cause less often seen in younger patients, was the most common primary disease among our elderly dialysis patients. As we previously reported, vascular and valvular calcification are important factors for determining prognosis; however, no significant relationships were observed in the present study, probably because almost all the patients had such calcifications.

Removal of the peritoneal dialysis catheter because of gastrointestinal disease in patients on continuous ambulatory peritoneal dialysis: a single-center case series.

We previously reported that peritoneal dialysis (PD)-associated peritonitis is a major cause of PD catheter removal. Another major cause is disease of the gastrointestinal tract, including neoplasm and perforation. In the present study, we reviewed the records of patients who underwent catheter removal at our hospital for reasons other than peritoneal infection--and for gastrointestinal disease in particular. Data were collected from the records of patients who received continuous ambulatory PD (CAPD) therapy between 2004 and 2010 at the Department of Nephrology, Saitama Medical University. Mean duration of CAPD was 6.2 +/- 4.7 years, and mean age at onset was 64.5 +/- 9.6 years. During the investigation period, catheters were removed from 13 patients (4 men, 9 women) because of gastrointestinal disease: gastric cancer in 3 cases, colon cancer in 3 cases, perforation of the lower gastrointestinal tract in 3 cases, and other reasons in 4 cases. Examination of pathology specimens obtained from 6 patients-including 1 in whom contrast-enhanced computed tomography indicated the presence of encapsulating peritoneal sclerosis (EPS)-revealed mild fibrosis in the subserous layer. No patient died of infection after a surgical procedure. Moreover, throughout the observation period, no patient developed new EPS or postoperative ileus. The present study suggests that CAPD itself seems to be free of untoward effects during the postoperative course in these patients.

[Association between long-term smoking and hypertension and early-onset nodular glomerulosclerosis].

Diabetic nodular glomerulosclerosis, also known as Kimmelstiel-Wilson syndrome, is a specific pathological variant of diabetic nephropathy ; however, histological findings similar to diabetic nephropathy are observed occasionally without glucose intolerance. Therefore, such nodular glomerulosclerosis is called idiopathic nodular glomerulosclerosis. Several case reports that have been published recently indicate that smoking and hypertension, which are classical renal risk factors, may be attributed to this form of glomerular degeneration. Accordingly smoking- and hypertension-associated nodular glomerulosclerosis has been considered to be different from the idiopathic form. This novel form of nodular glomerulosclerosis is associated with a history of long-term smoking and hypertension, and the age of onset of this disease is more than 60 years. We present the case of a 27-year-old Japanese male who was admitted to our hospital with nephrotic syndrome, hypertension, and renal impairment. He had a smoking history of at least 13 years, and had been exposed to passive smoking for several years because his parents were smokers. Renal biopsy revealed diffuse and global nodular glomerulosclerosis, although the patient did not have any primary diseases such as diabetes mellitus or paraproteinemia, that can cause this condition. We diagnosed smoking- and hypertension-associated nodular glomerulosclerosis. Cessation of smoking and the administration of an angiotensin II receptor blocker decreased his proteinuria and showed recovery of kidney function. This case report suggests that long-term smoking is closely associated with nodular glomerulosclerosis. Further, in our case, the age of the patient was lower than that of patients with the same disease among cases that have been reported previously.

Height constitutes an important predictor of mortality in end-stage renal disease.

Aim. Height is an important determinant of augmentation index (AI) that anticipates cardiovascular prognosis. There is a scanty of the data whether short height predicts survival in patients with end-stage renal diseases, a high risk population. Methods. Fifty two hypertensive patients with type 2 diabetic nephropathy receiving hemodialysis and 52 patients with nondiabetic nephropathy were enrolled. In addition to AI estimated with radial artery tonometry, classical cardiovascular risk factors were considered. Patients were followed for 2 years to assess cardiovascular prognosis. Results. Cox hazards regression revealed that both smoking and shortness in height independently contributed to total mortality and indicated that smoking as well as the presence of left ventricular hypertrophy predicted cardiovascular mortality. Our findings implicated that high AI, the presence of diabetes, and low high-density lipoprotein cholesterol were significant contributors to cardiovascular events. Conclusions. Our findings provide new evidence that shortness in height independently contributes to total mortality in hemodialysis patients.

Granulomatous interstitial nephritis in chronic lymphocytic leukaemia.

We present a case of granulomatous interstitial nephritis (GIN) associated with chronic lymphocytic leukaemia (CLL). GIN is a rare pathological finding noted in renal biopsy specimens. Furthermore, CLL does not usually cause GIN. In this case, acute renal injury probably resulted from GIN, and urgent dialysis was required, despite sufficient chemotherapy. Immunohistochemical analyses of a biopsy specimen revealed invasion of CD20( +) CLL cells, surrounded by reactive T cells, and granuloma formation. Thus, CLL may induce secondary interstitial nephritis as a granulomatous reaction.

Seasonal variations of daily changes in blood pressure among hypertensive patients with end-stage renal diseases.

Hypertension is a well-known cardiovascular risk. Patients with end-stage renal diseases frequently suffer hypertension, and their blood pressure elevates in winter. However, seasonal changes in daily variations of blood pressure are poorly assessed in patients treated with hemodialysis. Thirty hypertensive patients with end-stage renal diseases were enrolled in the study. Dry weight and antihypertensive medications were altered when they were necessary. Home blood pressure measurements were performed at least for 1 week in each season; April-May 2008, July-August 2008, October-November 2008, and January-February 2009. Both morning and evening systolic blood pressures (SBPs) showed significant seasonal changes ( p < 0.01), with the highest blood pressure in winter (162 +/- 18 and 135 +/- 22 mmHg in morning and evening). Morning diastolic blood pressure (DBP) also exhibited seasonal changes ( p < 0.05), with the highest blood pressure in fall ( 78 +/- 8 mmHg). Evening DBP did not manifest seasonal deviations. Morning-evening differences in SBP and DBP were the greatest in winter (28 +/- 21 and 10 +/- 9 mmHg in SBP and DBP, p < 0.01), and the smallest in summer (16 +/- 12 and 6 +/- 5 mmHg). Daily variations of SBP and DBPs in spring (19 +/- 12 and 7 +/- 6 mmHg) and fall (20 +/- 13 and 9 +/- 8 mmHg) were between those of summer and winter. Our results indicate that not only averaged blood pressure but also variations of blood pressure in winter are larger than the other seasons, and suggest that these blood pressure variations participate in cardiovascular events in hypertensive patients with end-stage renal diseases.

Zigzagged augmentation index in diabetes.

Although the patients with diabetic nephropathy suffered high cardiovascular risk, augmentation index (AI) in diabetic nephropathy has been poorly characterized. Cross-sectional studies were performed on 26 diabetic and 27 nondiabetic nephropathic patients. Home blood pressure was examined. In addition, blood pressure, pulse rate, and AI were measured in both supine and sitting positions. Patient backgrounds such as age, sex, sitting blood pressure, and pulse rate were similar between two groups. Circadian variations of home blood pressure were preserved in nondiabetic patients, but disappeared in diabetes. Changing from supine to sitting position induced greater decrements of systolic blood pressure (DeltaSBP -9 +/- 8 mmHg) and AI (DeltaAI -7 +/- 10) in the diabetic group than in nondiabetic patients (DeltaSBP -4 +/- 12 mmHg, DeltaAI -2 +/- 9). Multivariate regression analysis revealed that AI in a sitting position correlated positively to SBP and inversely to pulse rate. Of interest, AI in supine position related positively to age, the presence of diabetes and SBP, and inversely to pulse rate. The present data indicate autonomic dysfunction in patients with diabetic nephropathy. Furthermore, our findings provide the evidence that autonomic dysfunction elicits an inadequate physiological arterial contraction in response to postural change, thereby reducing AI that results in the fall of SBP. Finally, the present results suggest that AI in supine, but not sitting position, is suited for detecting cardiovascular risk in diabetes.