Factors related to renal haemodynamics in young type-1 diabetes mellitus patients

The influence of metabolic control (HbA_1c), noradrenaline (NA) and insulin-like growth factors (IGF-I and IGF-II) on renal function and size was investigated in 11 insulin-dependent diabetes mellitus patients aged 11–17 years. Renal function was evaluated in terms of glomerular filtration rate (GFR) and effective renal plasma flow (ERPF). Renal size was determined as renal parenchymal volume (RPV) by ultrasonography. The patients' HbA_1c values ranged from 8.2% to 12.9% (normal range 5.5–8.5%) and their GFR and ERPF were higher than normal. Their IGF-II values were higher, and NA and IGF-I levels were lower than those of healthy controls. Inverse correlations between NA and GFR (r=–0.66) and NA and ERPF (r=–0.63) were found. No correlation was found between serum IGF-I and renal functional parameters. The IGF-II values correlated with GFR and HbA_1c (r=0.63,r=0.70 respectively). There were linear correlations between RPV and GFR, RPV and ERPF, HbA_1c and GFR, and ERPF and RPV. Decreased NA concentrations and increased IGF-II values appear to be factors contributing to renal hyperfunction in these patients.     

Post-biopsy arteriovenous fistulas of the native kidneys diagnosed by Doppler US

Two patients with arteriovenous fistulas of the native kidney occurring after needle biopsy were evaluated using duplex and color Doppler ultrasonography. The first patient had a fistula with associated pseudoaneurysm: color Doppler showed the lesion as a small rounded area with whirling flow; spectral analysis allowed recognition of both the afferent artery with low impedance flow and the draining vein with pulsatile, arterialized flow. The second patient had a normal color Doppler study; however, spectral analysis demonstrated signals with low vascular impedance from an intra-parenchymal artery at the lower pole, and a jet of turbulent flow. Following disappearance of clinical findings, such Doppler abnormalities were no longer detectable. When a iatrogenic arteriovenous fistula is considered on clinical grounds, both color and Doppler spectral analysis of waveforms from intra-parenchymal vessels should be performed. Possibly, further advances in color Doppler technology will permit the use of this examination as the first imaging procedure in these clinical situations.Correspondence to: L. E. Derchi     

流行性出血热若干体液因子和肾脏血液动力学的变化

对28例流行性出血热（EHF）患者作了体液因子和肾脏血液动力学的观察研究。发现患者从发热期至多尿初期血浆内皮素（ET）、血栓素B2（TXB2）、血管紧张素-Ⅱ（AT－Ⅱ）均高于正常，P物质（SP）则低于正常，6-酮前列腺素F1α（6-k-PGF1α）除极期外其它各期亦见减低，肾小球滤过率（GFR）与肾有效血浆流量（ERPF）从发热后期至多尿期均显著下降，至恢复初期多数重型患者仍未达到正常。上述结果提示体液因子的失衡是造成内脏缺血和急性肾衰的重要因素。     

镉对肾脏的毒作用

雄性Ｗｉｓｔａｒ大鼠２４只，随机等分为４组，皮下注射不同剂量的ＣｄＭＴ。结果显示镉接触组尿钙和尿蛋白都高于对照组；肾皮质钠泵和钙泵活性低于对照组，体外试验也显示镉能抑制钙泵活性，ＧＳＨ和半胱氨酸对这种抑制有保护作用；肾皮质ＧＳＨ含量低于对照组，ＭＤＡ含量则高于对照组，但肝脏的这两个指标无变化；高剂量组ｃＡＭＰ／ｃＧＭＰ的比值低于对照组。提示脂质过氧化和钙代谢障碍是镉引起肾损害的机理之一。     

Renal vascular resistance in normal children – a color Doppler study

To investigate the relationship between age and renal vascular resistance and to establish nomative data of the systolic/diastolic ratio (S/D ratio), pulsatility index (PI), and resistant index (RI) of the renal artery in the normal pediatric population, we studied 252 normal children aged newborn to 13 years (a total of 449 kidneys) with a color Doppler unit. After the normality of the kidney was established, color flow mapping was performed to localize the segmental portion of the renal artery. Flow velocity waveforms were then obtained by pulsed Doppler, and S/D ratio, PI, and RI were calculated. Multiple regression analysis confirmed the age dependence of the S/D ratio, PI, and RI of the renal artery in normal children. Renal vascular resistance continuously declines after birth and stabilizes at the age of 102 – 130 months. Normative data for S/D ratio, PI, and RI of the renal artery in normal children were established for each age group. Since renal vascular resistance decreases with age and stabilizes at 8 – 10 years, we suggest using different normal ranges for each age group when studying renal vascular resistance in pediatric patients. Received October 5, 1995; received in revised form and accepted April 24, 1996     

Sialic acid concentrations in the urine of men with and without renal stones

Summary It has been suggested that urinary sialidase may play a role in the formation of renal stones. The present study was therefore undertaken to compare spectrophotometrically the different types of sialic acid concentrations and sialidase activities in fresh first morning urine specimens of men (21–65 years) with (13) and without (9) calcium oxalate renal stones. Although the free urinary sialic acid concentrations of the two groups of men were statistically about the same (P=0.0614), the total (P=0.003) and bound (P=0.0012) urinary sialic acid concentrations differed significantly. Both the total and bound sialic acid concentrations were lower in the urine specimens of the stone patients than in their healthy counterparts. This decrease in urinary sialic acid concentrations was firstly thought to be the result of elevated breakdown enzymes of sialic acid, which would favour the production of pyruvate. However, spectrophotometric determinations of the endogenous pyruvate concentrations of the two types of urine specimens did not differ significantly (P=0.0708). Secondly, the decrease in total urinary total sialic acid concentration of stone patients, could be attributed to less sialic acid synthesis or less renal excretion. Therefore, the same experiments were repeated using serum of 13 patients and 9 healthy men. Conversely, the total (P=0.4425) and bound (P=0.2850) serum sialic acid concentrations were found to be similar in the two types of subjects. However, the free serum sialic acid concentration of stone patients was significantly lower than in the healthy subjects (P=0.0062). This phenomenon is also reflected in the average ratio for serum free: bound sialic acid in healthy and stone patients, 1:7.9 and 1:18.7 respectively (P=0.0009). The lower free serum sialic acid concentration may lead to lower renal excretions of sialic acid. This may explain the decrease in total urinary sialic acid concentration in stone patients. The lower bound urinary sialic acid concentrations in patients was also reflected in the urinary free: bound sialic acid ratio for healthy (1:2.3) and stone patients (1:1.3). The difference between these two groups of men was highly significant (P=0.0001). This phenomenon might be explained by the urinary sialidase activities, which was spectrophotometrically determined at 334 nm at 37°C of 11 patients with stones and 17 healthy men. The ages of both groups of men were the same (P=0.326). An increase in urinary sialidase activity was observed with the stone patients (P=0.00001) when compared to specimens of healthy men. This might explain the decrease in urinary bound sialic acid concentration of the stone group. It seems from these results that the urinary concentration of sialic acid and the activity of urinary sialidase, may play a role in the pathogenesis of the multifactorial disease, urolithiasis.     

Posterior urethral valves in patients with Down syndrome

Renal and urological anomalies in Down syndrome (DS) have received little attention compared with the nephrourological findings described in other chromosomal abnormalities. Renal hypoplasia, hydroureteronephrosis, ureterovesical and ureteropelvic junction obstruction, and vesicoureteral reflux, but not posterior urethral valves, have been associated with DS. We report the occurrence of posterior urethral valves in three male infants with DS at a single institution. All had multiple urological procedures for correction or palliation of obstruction. Children with DS may have an increased risk for developing posterior urethral valves and obstructive uropathy. Furthermore, they may also develop chronic renal failure secondary to posterior urethral valves. Therefore, we suggests that infants with DS be screened with ultrasonography for renal and urological abnormalities early in life and, if abnormal, a contrast voiding cystourethrogram be performed to rule out posterior urethral valves or other bladder or urethral abnormalities. A review of the renal and urological anomalies in DS reported in the literature since 1960 is presented.     

经皮肾囊穿刺封闭术治疗难治性肾病综合征临床研究

目的　探讨介入疗法对难治性肾病综合征 (RNS)的疗效。方法　将 6 4例RNS随机分为A ,B两组 ,A组 32例 ,经皮肾囊穿刺向每一肾脂肪囊 (肾囊 )内注入 2 %利多卡因 ,每周 2次 ,同时口服强的松、洛汀新、潘生丁等治疗 ,B组 32例 ,应用强的松、洛汀新、潘生丁等治疗。结果　A组总有效率为 84 .4 % ,B组为 6 5 .6 % ,两组比较 (P <0 .0 5 ) ,A组 1年内复发率低 ,为 2 9.6 % ,B组为 71.4 % ,比较两组 (P <0 .0 1)。结论　利多卡因经皮肾囊内穿刺注射封闭疗法是目前治疗RNS最有效的方法之一 ,值得临床进一步的推广应用。     

Zinc deficiency and hyperprolactinaemia are not reversible causes of sexual dysfunction in uraemia

We selected a group of male dialysis patients complaining of sexual dysfunction in whom penile vascular insufficiency and drug-induced impotence had been excluded. Monitoring of nocturnal penile tumescence was used to confirm organic disturbance. Patients with normal serum prolactin concentrations (n = 18) had significantly lower serum zinc values than normal controls (P less than 0.001) and were entered in a 6-month double-blind study comparing oral zinc acetate with placebo. Patients with elevated prolactin concentrations (n = 8) were entered in a 3-month double-blind crossover study comparing oral pergolide mesylate with placebo. In the zinc study, serum zinc concentrations increased (P less than 0.05) in the zinc-treated but not the placebo-treated group. One of nine patients receiving zinc reported improved sexual function, as did two of nine patients receiving placebo. There were no significant changes in sperm counts, nocturnal penile tumescence, testosterone, sex hormone binding globulin or gonadotrophin concentrations in either treatment group. In the pergolide study, serum prolactin values decreased (P less than 0.01) in the pergolide but not in the placebo treatment period. One patient reported improved sexual function during the pergolide treatment period and two during the placebo period. There were no significant changes in sperm counts, nocturnal penile tumescence, testosterone, sex hormone binding globulin or gonadotrophin concentrations after pergolide. These studies show no benefit of zinc or pergolide compared with placebo in the treatment of uraemic impotence.     

前列腺素E1对尸体肾移植术后肾功能延迟恢复的影响

目的探讨前列腺素E1(PGE1)应用于尸体肾移植术后肾功能延迟恢复(DGF)患者对移植肾功能恢复的影响.方法回顾性分析因急性排斥(AR)和急性肾小管坏死(ANT)导致DGF的127例临床资料,其中应用PGE1治疗56例(PGE1组),未用PGE1者71例(对照组).比较两组在出现DGF后的透析治疗时间、肾功能恢复情况、彩超的移植肾血流阻力指数(RI)及6个月内AR发生率.结果与对照组比较,PGE1组透析治疗时间明显缩短(P＜0.05),移植肾的血肌酐下降速度快(P＜0.05),RI及6个月内AR发生率低(P＜0.05).结论PGE1有利于尸体肾移植术后DGF患者移植肾功能的早期恢复,并能降低AR的发生率.