Child nephrology and urology最新文献

The frequency of acquired cystic kidney disease (ACKD) in adult patients with end-stage renal failure (ESRF) varies from 8 to 95%. Systematic data are available neither on children with chronic renal insufficiency (CRI) nor on the frequency of ACKD in children below 15 years undergoing dialysis. Twenty-one children with CRI and 28 patients with ESRF were investigated. The age of the children ranged from 1 month to 15.8 years. Ultrasonographic examination determined the incidence of ACKD; in some children computerized tomography was performed. ACKD was diagnosed in 2 children (9.8%) with CRI and in 6 (21.6%) with ESRF. Diagnostic criteria and evolution of ACKD within the observation period of 3-48 months (mean 23.4 +/- 12.6 months) are discussed.

Rats made uremic by 2-stage 5/6 nephrectomy and sham-operated control animals were fed either a normal laboratory chow, a high-sucrose (60%) or a high-fat (10% cholesterol; 20% olive oil) diet, all containing 21% protein and identical amounts of electrolytes, vitamins and trace elements. Serum creatinine levels remained unchanged in the control animals but rose in the 5/6 nephrectomised uremic animals by a factor of 2.7 from a mean of 0.44 +/- 0.05 mg/dl to 1.20 +/- 0.11 mg/dl at 8 weeks, without differences between the dietary groups. During 8 weeks of dietary regimen the high-sucrose and high-fat diets induced significant hypertriglyceridemia, generally similar in control and uremic rats. The uremic animals on a high-sucrose and high-fat diet had the most pronounced rise in serum triglycerides, 331.5 +/- 89.0 and 298.0 +/- 45.0 mg/dl, respectively (control: 159.9 +/- 14.0 mg/dl). After 4 and 8 weeks, only the animals on the high-fat diet had significant hypercholesterolemia, most pronounced in the uremic animals (356 +/- 56.3 mg/dl; control: 71.6 +/- 12.9 mg/dl). The animals in the latter group also had significant proteinuria and renal histologic abnormalities consisting of xanthoma-like glomerular lesions, infiltrates and fibrosis not seen in the other groups of animals. These data indicate that dietary-induced hyperlipidemia of short duration causes or aggravates renal damage in the rat with mild-moderate uremia, induced by ablation.

The deterioration rate of creatinine clearance (CCr) was studied in 40 children with chronic renal failure (CRF) on conservative treatment followed up for at least 1 year (range 1-12). The deterioration rate of CCr was significantly (p less than 0.01) higher in glomerulopathies (G) than in hypoplasias (H) and in vascular nephropathies (VN) and significantly (p less than 0.01) higher in hereditary nephropathies (HN) than in VN. The differences in the deterioration rate of CCr between H and HN and between H and VN were not explainable on the basis of the different age at diagnosis or of the different prevalence of hypertension. These data indicate that the primary renal disease is important in determining the progression of CRF.

The incidence of hypertension (HT) in renal parenchymal disease of the young is very high, varying from 38 to 78%. This points to the central role of the kidneys in normal blood pressure control. HT in chronic renal failure (CRF) and end-stage renal disease (ESRD) depends on the nature of the underlying disease. The degree of renal failure has a highly variable effect. The clinical signs and symptoms of this form of HT are often superimposed on those of the basic (renal) disorder. The pathogenesis of HT in CRF is dominated by volume- and renin-mediated mechanisms. In addition, a wide variety of humoral and neural factors play a role. The HT seen in patients on renal replacement therapy (RRT) and after renal transplantation (Tx) poses special problems. In this paper these various aspects of HT in CRF are discussed and the principles of treatment are reviewed. It has been shown beyond any doubt that control of HT in young patients with CRF and ESRD, treated conservatively or on RRT and after renal Tx is of utmost importance for their long-term outcome. This is an important challenge for all pediatricians looking after young patients with CRF and ESRD.

Excellent survival data and rewarding rehabilitation have been reported following kidney transplantation. Annual mortality decreases with time after transplantation and has dropped below 2% in children and below 3% in young adults. No major single cause of death has been identified. Short-term graft survival rates are still improving but no major breakthrough in long-term graft maintenance has been achieved. The major cause of graft failure is chronic rejection. Major causes of morbidity in long-term graft recipients are: hypertension occurring in 65-75% of the recipients, avascular necrosis of the bone resulting in severe disabling in 4% of transplant recipients and growth retardation. Also, in patients receiving a kidney transplant during childhood, an increased risk of de novo malignancy development was reported. Full rehabilitation is often hampered by physical disabilities and will restrict social life. However, the possibility of obtaining employment is not different from that of the general population. The evaluation of morbidity in long-term kidney transplant survivors requires the collaboration of larger pediatric transplantation centers.

One hundred and four children developed typical post-diarrhea hemolytic uremic syndrome (D+ HUS) over an 11-year period. Four of the children died in the acute stage. Two of the children died from a central nervous system complication which was attributable to the HUS process. One child died suddenly without any explanation. The 4th child died following a cardiovascular collapse, perhaps related to septic shock. The literature on the causes of death in children with HUS is reviewed.

To explore the age-related changes in tubular function and in the renal reserve (RR) a total of 98 healthy subjects were studied while on free living conditions. Enrolled people were divided into 3 groups: group A (n = 40, age range 5-18 years, Na intake 80 +/- 20 mM/day, protein intake 1.30 +/- 0.76 g/kg BW); group B (n = 34, age range 19-60 years, Na intake 110 +/- 12 mM/day, protein intake 1.32 +/- 0.75 g/kg BW), and group C (n = 24, age range 61-89 years, Na intake 159 +/- 12 mM/day (p less than 0.01 vs. A and B), protein intake 1.26 +/- 0.23). Glomerular filtration rate (GFR) (inulin), renal plasma flow (p-aminohippurate), the amount of filtrate and sodium delivered from the proximal tubule (lithium clearance), endogenous creatinine clearance, and predicted creatinine clearance were measured. The RR was evaluated after a meat meal (providing 2 g/kg BW of proteins) by subtracting baseline GFR from the peaking postprandial GFR. GFR was age-related and was identical in groups A and B and significantly lower in group C (p less than 0.0001). The drop in GFR averaged 7% per decade in the age range 61-89 years. The RR was not statistically different in groups A and B and increased significantly in group C (p less than 0.0001). In groups A and B the filtration fraction was constant after the meat meal and significantly increased over baseline GFR in group C (p less than 0.01), while the percentage of filtration capacity utilized at rest was lower in group C (p less than 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Management of the pediatric renal-transplant recipient requires careful pretransplant evaluation including psychosocial assessment and cautious donor/recipient selection. Early transplantation is preferable in infants less than 1 year of age if a suitable live-related donor is available. However, cadaveric-allograft transplantation is best reserved for patients older than 3 years with donors older than 5 years. Pre-emptive transplantation is suitable for approximately one fifth of the population. Medical preparation includes careful HLA-A, -B, and -DR loci matching, interferon treatment for positive hepatitis antigenemia, and acyclovir prophylaxis for a cytomegalovirus (CMV) antibody-negative patient to a seropositive donor. Postoperative management requires close monitoring of the patient's volume status with careful fluid replacement in the form of colloid and crystalloid. Immunosuppression involves multiple drug regimens that include corticosteroids, ciclosporin, azathioprine, antilymphocyte (or -thymocyte) globulin (ALG/ATG), monoclonal antibodies (OKT3), and a ciclosporin alternative: FK-506. Long-term complications dictate management and are divided into medical, surgical, immune, and infectious categories. These are predominated by treatment of acute and chronic rejection, hypertension, and CMV infection.

The site of action of atrial natriuretic peptides (ANP) in man remains uncertain. In this study the attention was focused on the proximal tubule. Three markers of the proximal tubular reabsorption were used as a tool: lithium, amino acids and beta 2-microglobulin. The reabsorption of these three substances was decreased during ANP infusions in 3 normal sodium-replete male volunteers. These findings suggest that ANP not only decreases distal sodium reabsorption, but also proximal fractional tubular sodium reabsorption in man.