Clinical Queries: Nephrology最新文献

Restless Leg Syndrome and Periodic Limb Movements (RLS/PLM) are a common form of sleep disturbance in Chronic Kidney Disease (CKD) patients. The pathophysiology is related to the iron deficiency, anemia of renal disease, uremic toxin accumulation resulting in encephalopathy and peripheral neuropathy. Diagnosis of the condition is made by clinical criteria and rarely polysomnography. RLS/PLM is associated with poor quality of life and increased morbidity and mortality in CKD. Therapeutic approaches include nonpharmacologic, pharmacologic and specific interventions for CKD patients.

Vascular complications after renal transplant are not common, but important cause of graft loss and graft failure. Transplant renal artery stenosis (TRAS) is the most common vascular complication. It usually occurs 3 months to 2 years after transplant. Stenosis may occur (1) at the anastomosis site, (2) as a focal stenosis either proximal or distal to anastomosis, or (3) as diffuse (narrowing of whole artery), multiple stenosis (simultaneous narrowing at multiple sites). Stenosis at site of anastomosis is common occurring in approximately 50% of cases and end-to-end anastomosis have a threefold greater risk of stenosis than end-to-side anastomosis. Usual clinical presentation of TRAS is resistant/worsening of hypertension with or without renal dysfunction. Color Doppler ultrasound is preferred method for screening and intraarterial angiography is gold standard for diagnosis of TRAS. Percutaneous transluminal renal angioplasty (PTRA) is treatment of choice for TRAS. Surgery is indicated for patients with unsuccessful angioplasty or with very severe stenosis that are inaccessible to PTRA.

Cardiovascular disease (CVD) continues to account for a very high percentage of deaths in patients with ESRD. An entire gamut of risks factors-some well known, some still being understood and yet more putative are operational in patients with renal disease. CVD assumes enhanced importance in the wake of its disproportionate effect on patients with uremia. Some studies have reported an upto 15 fold higher cardiovascular death rate in patients on PD when compared to non-uremic cohorts. Thus it follows that the longevity of patients on PD is directly related to improvements in the recognition, management and prevention of CVD. While the conventional risk factors like age/diabetes/hypertension/hyperlipidemia/smoking etc need no elaboration, factors unique to renal failure like calcium/phosphorus/Vitamin D abnormalities, anemia, dialysis related chronic inflammation etc add to the burden and pathogenesis of CVD. Specific to PD, certain abnormalities like hypoalbuminemia and attendant malnutrition, metabolic abnormalities and even high transporter status (speculative) are thought to propagate the progression of CVD. A review of CVD in PD is incomplete without a referral to non-atherosclerotic disease-volume overload, congestive heart failure and LVH. This review looks into the spectrum of CVD in PD patients, its pathogenesis, and factors unique to PD, and possible therapeutic and preventative measures.

Renal tubular acidosis is a collection of renal tubular disorders of diverse etiopathological states that present with hyperchloremic metabolic acidosis due to failure of net renal acid excretion. This review attempts to simplify the underlying physiological basis, the pathophysiological patterns, and the clinical manifestations. An algorithmic approach to diagnose RTA along with a description of most of the tests used is provided. The clinical approach to RTA is followed by a brief note on its therapy.

The survival of patients on hemodialysis is very poor when compared to kidney transplantation. Several attempts have been made to improve the survival of dialysis patients. Some such attempts are more frequent dialysis, more prolonged dialysis, use of high flux dialyzers, use of ‘ultrapure’ dialysate, and better electrolyte and mineral metabolism. Hemodiafiltration is one such measure, where both diffusive and convective methods of toxin removal are exploited with a view of removing both small molecular weight and larger molecular weight toxins from the body. Over last 2 decades several studies with confronting results regarding hemodiafiltration and survival outcome are published and hence need for a review.

Bioelectrical Impedance Analysis (BIA) is a noninvasive and bedside tool for assessment of nutritional status. It is expected that patients who have undergone successful renal transplant will have good nutritional intake and steadily the patient will return to normal health and have good nutritional status.

Objective

The aim of the study was to evaluate effect of graft function on nutritional status in post renal transplant patients with borderline to good allograft function using BIA.

Material and methods

For this study, 45 post-renal transplant patients with mean serum creatinine 1.42 ± 0.42 mg% and glomerular filtration rate (GFR) 45.1 ± 14.1 ml/min were subjected to bioimpedance analysis. Several parameters were evaluated. Based on BIA derived GFR, patients were divided into two groups (group 1: borderline graft function GFR < 40 ml/min, X = 27.34 ± 9.1 ml/min and group 2: good graft function GFR ≥ 40 ml/min, X = 51.60 ± 9.16 ml/min). Patient data were compared with 30 healthy individuals.

Results

There was significant difference between healthy controls and the post transplant patients. Based on GFR, there was significant difference in patient groups in body weight (p = 0.01), serum creatinine (p = 0.005), BMI (p = 0.000), fat free mass (p = 0.003), fat mass (p = 0.003), body cell mass (p = 0.000), dry weight (p = 0.001). Patients with borderline GFR had higher serum creatinine but significantly lower body weight, BMI, FFM, FM, and dry weight, indicating poorer nutritional status as compared to those with good graft function. Based on phase angle, there was significant difference between groups A and B in GFR (p = 0.000), extracellular water (p = 0.015), intracellular water (p = 0.002), plasma fluid (p= 0.016), interstitial fluid (p = 0.016), body cell mass (p = 0.024). SGA scores showed that transplant patients had normal nutritional status, but when compared with healthy individuals, there was significant difference in the fat mass, fat free mass and body cell mass as assessed by BIA.

Conclusion

Compared to patients with good graft function, patients with borderline GFR showed evidence of early nutritional depletion as picked up by BIA implying nutritional deficiency sets in with reduction in GFR (<40 ml/min) which may not be picked up by subjective global assessment but is objectively detected by BIA.

Atherosclerotic plaques are prone for thromboembolism with clots and atheroembolisation with cholesterol crystals. Atheroembolism occurs when the atherosclerotic plaque is disrupted causing multiple showers of cholesterol crystal embolization resulting in partial or total occlusion of small arteries of multiple organs. Atheroembolic renal disease (AERD) refers to cholesterol crystal embolization of the renal arteries and is often associated with multiorgan involvement. Diagnosis requires a high degree of suspicion in the clinical setting with renal failure, skin lesions, and sometimes hypocomplementemia and eosinophiluria. Treatment is mainly supportive and overall prognosis is poor.

Congenital abnormalities of kidney and urinary tract are the leading cause of end-stage kidney disease in children. These result from genetic as well as environmental causes. The embryology of kidney and urinary tract is modified by genetic mutations leading to CAKUT. These anomalies may occur in isolation or as a part of syndrome with renal as well as non-renal manifestations. The phenotype may vary from asymptomatic abnormalities on one hand to renal agenesis on the other. Lower tract abnormalities are frequently associated. Many of the disorders may be diagnosed antenatally on imaging. Proper antenatal and post-natal management may prevent progression to ESKD. The role of genetics in diagnosis remains unclear at present and needs further evaluation.

Renal dysfunction is commonly seen in patients with end stage liver disease. Prognosis of patients who develop hepatorenal syndrome (HRS) is dismal with a median survival of around six months without liver transplantation. Advances in understanding of the pathophysiology of HRS has lead to evolving ideas regarding the definition and diagnostic criteria of HRS. In addition, recent pharmacological and other therapeutic innovations provide hope to patients of HRS. This is a review of diagnostic criteria, etio-pathogenesis and therapeutic options for patients of HRS based on the available evidence in literature.

Despite improved survival, renal transplant recipients remain at a high risk of increased mortality and mortality from cardiovascular disease. Both traditional cardiovascular disease (CVD) risk factors and those unique to this population add to the burden of disease, making their CVD risk 50 times that of the general population. This article discusses our present understanding of cardiovascular disease, the risk factors, including dyslipidemia, hypertension, allograft rejection and dysfunction, anemia, proteinuria and new onset diabetes after transplantation (NODAT), as well as prevention and management of these risk factors. Cardiovascular interventions as well as future considerations are also briefly discussed.