Use of creatinine clearances to monitor the effect of low-dose dopamine in critically ill surgical patients

INTRODUCTION: Despite uncertain evidence of its efficacy, "low-dose dopamine" (2-5 microg/kg/min) has often been used to augment renal perfusion in critically ill surgical patients. The 2-h creatinine clearance (CC) has been shown to be a monitor of renal function in critically ill patients. We therefore studied the use of sequential CC determinations to monitor the effect of low-dose dopamine (LDD) in surgical intensive care unit (SICU) patients. We hypothesized that sequential CC measurements could demonstrate whether individual patients had positive responses in renal function to LDD. METHODS: Data were prospectively collected for patients on LDD in a university SICU. CC were recorded for these patients immediately before and after the institution of LDD or before and after the cessation of LDD. APACHE II scores, gender, urine creatinine, age, blood pressure, heart rate, and urine output (UO) were also recorded for these patients; P < 0.05. RESULTS: Twenty-four pairs of CC values were observed during the study. The mean APACHE II score for the patients was 15.1. In 10 cases after initiation of LDD, the mean CC increased from 52.5 +/- 23.7 ml/min to 68.1 +/- 33.8 ml/min (P = 0.056). UO also increased from 48.0 +/- 27 to 75.9 +/- 49 ml/h (NS). In 14 cases after discontinuation of LDD, CC decreased from 85.6 +/- 36.3 ml/min to 63.6 +/- 45.5 ml/min (P = 0.044) and UO decreased from 105.1 +/- 73.9 to 89.6 +/- 76.7 ml/h (NS). Overall, 13 of the 24 patients had a 25% change or more in CC upon initiation or cessation of LDD. CONCLUSIONS: LDD institution increased CC in individual patients in the SICU population. Because using LDD in the absence of a discernable improvement in renal function is costly and may harbor risks, we recommend following CC in patients on LDD to determine which patients derive benefit from the intervention.     

Reversible acute renal failure associated with hypothyroidism: report of four cases with a brief review of literature

SUMMARY:   We present four adult cases of acute renal failure associated with hypothyroidism. All patients presented with symptoms suggestive of moderate to severe hypothyroidism, such as cold intolerance, constipation, muscle weakness, and lower extremity oedema. Initial serum creatinine levels ranged between 115 and 203 µmol/L (1.3 and 2.3 mg/dL), with creatinine clearances (CrCl) ranging between 0.58 and 0.97 mL/s (34.5 and 58 mL/min). After 6–12 weeks of treatment with levothyroxin, serum creatinine levels decreased to the range of 80 and 124 µmol/L (0.9 and 1.4 mg/dL) and CrCl increased to 0.74–1.64 mL/s (44–98 mL/min). One patient had proteinuria of 800 mg/day, which decreased to the normal range (<200 mg/day) after levothyroxin treatment. One patient developed acute gouty arthritis before normalization of thyroid-stimulating hormone (TSH), which was successfully managed with prednisone therapy. All of our patients had increased creatine kinase (CK), ranging between 1000 and 2360 U/L (normal range, 22–165 U/L), which normalized after 6 weeks of levothyroxin treatment.     

A combined ultrasonic and biochemical study of fetal renal function in the term fetus.

The fetal glomerular filtration rate of plasma (GFR) and the percentage of fetal tubular reabsorption of water were measured by means of combined ultrasonic and biochemical methods in 20 normal and 10 complicated pregnancies. The duration of pregnancy varied from 35 to 42 wk. In normal pregnancy GFR of plasma varied from 2.0 to 7.1 ml/min (mean = 4.1) and tubular reabsorption of water ranged from 84.1 to 93.0% (mean = 89.8). There was no relationship with gestational age. In the group of complicated pregnancies - apart from one anencephalic case - no apparent difference in GFR and percentage tubular reabsorption between the group of normal (greater than or equal to 10th percentile) and reduced fetal birth weight (less than 10th percentile) was observed.     

Paired kidney analysis of tacrolimus and cyclosporine microemulsion-based therapy in Chinese cadaveric renal transplant recipients

Few studies used paired kidneys for comparison between tacrolimus and cyclosporine in renal transplantation. Most of the published data used whole blood trough levels for drug monitoring. However, the use of limited sampling strategy and abbreviated formula to estimate the 12-h area under concentration-time curve (AUC(0-12)) allowed better prediction of drug exposure. Sixty-six first cadaveric renal transplant recipients receiving paired kidneys were randomized to receive either tacrolimus-based (n = 33) or cyclosporine microemulsion (Neoral)-based therapies (n = 33). Abbreviated AUC(0-12) was used for drug monitoring and dose titration. Mean follow-up duration was 2.8 +/- 2 years. The patient and graft survival were comparable. Fewer incidence of acute rejection was observed in tacrolimus group (15% vs. 27.3%) though the difference was not significant (P = 0.23). The absolute value and the rate of decline of creatinine clearance were both significantly better in tacrolimus-treated patients. Prevalence of hypertension, post-transplant diabetes mellitus, infection, and malignancy were similar in both groups. Prevalence of hypercholesterolemia (11/33 vs. 4/33) and gum hypertrophy (6/33 vs. 1/33) was more common in cyclosporine-treated patients (P = 0.04 in both parameters). This was the first prospective, randomized study with paired kidney analysis showing the renal function was significantly better in tacrolimus-treated patients than in cyclosporine-treated patients.     

Is deoxypyridinoline a good resorption marker to detect osteopenia in phenylketonuria?

OBJECTIVES: To evaluate deoxypyridinoline as a resorption marker in phenylketonuria (PKU) and to search for a relationship between deoxypyridinoline, calcium/creatinine index (Ca/Cr I), osteocalcin and bone alkaline phosphatase (BAP). METHODS: This was a transversal analytical study of 46 PKU patients [17.5 (4-38) years]. Deoxypyridinoline and osteocalcin were measured with a chemiluminescent assay and BAP was measured with an immunoradiometric assay. RESULTS: Deoxypyridinoline was significantly increased in patients aged 7-14 and >18 years old, being associated with age (r=-0.724, P<0.001). Adult patients showed significantly higher Ca/Cr I, which correlates with Phe values for the year prior to the study (P=0.014). Serum BAP was significantly increased in pediatric patients (9-13 years), while it was decreased in adult patients (P=0.003). Decreased osteocalcin levels were found in patients>15 years (P=0.028). Altered deoxypyridinoline and BAP values were related (P=0.042). CONCLUSION: PKU patients excreted increased D-Pyr, suggesting high bone resorption. Bone formation seems active in childhood but deteriorates in adult PKU patients. Periodic measurement of D-Pyr and BAP may be useful in the prevention of osteopenia in PKU patients.     

窒息新生儿心肌损害的早期诊断

目的探讨血清肌酸磷酸激酶同工酶(CK-MB)及心肌肌钙蛋白Ⅰ(cTnⅠ)对新生儿(MCI组)窒息心肌损害(MCI)的早期诊断价值。方法采用直接化学发光免疫夹心法和免疫抑制酶动力学法动态检测34例生后10 d内窒息并MCI新生儿(MCI组)血清cTnⅠ和CK-MB水平,并以38例窒息无心肌损害(NMCI组)及30例正常新生儿(NC组)作为对照组。结果NC组cTnⅠ水平在生后10 d内无变化,MCI组生后24 h内和1周时cTnⅠ水平均显著高于NMCI组和NC组(P均<0.01)。MCI组生后24 h内CK-MB水平显著高于NMCI组和NC组(P均<0.01);3组生后5~7 d检测值比较均无统计学差异(P均>0.05),且均明显低于生后24 h内水平。cTnⅠ诊断新生儿MCI的敏感度为91%,特异度为88%,准确度89%;CK-MB诊断新生儿MCI敏感度为85%,特异度为68%,准确度为74%。结论血清CK-MB及cTnⅠ均可用于新生儿窒息心肌损害的早期诊断,cTnⅠ优于CK-MB。     

儿童边缘性锌缺乏症综合判断的研究

对沈阳市某幼儿园９９例３～６岁锌缺乏儿童的营养调查和生物样品（血液、尿液和毛发）的分析发现：同对照组儿童相比，锌缺乏儿童除Ｆｅ、维生素Ａ外，其他主要营养素的摄入明显不足；缺锌儿童的发锌、ＲＢＣ锌水平、血清ＡＬＰ活性、尿锌／尿肌酐比值均明显低于对照组。经补锌治疗后血浆锌水平、血清ＡＬＰ活性、尿锌／尿肌酐比值显著升高。应用临床诊断实验的评价方法分析发现结合血浆锌水平，联合使用发锌，血清ＡＬＰ和尿锌／尿肌酐比值３项指标可以准确判断儿童边缘性锌缺乏，这时并联的灵敏度为９６．１８％，串联的特异度可高达到１００％（血清ＡＬＰ活性＜１０４ＩＵ／Ｌ，同时发锌含量＜１１０ｐｐｍ．尿锌／尿肌酐比值＜０．３μｇ／ｇ）。     

Association of Creatinine-to-Cystatin C Ratio with Myosteatosis and Physical Performance in Older Adults: The Japan Shimanami Health Promoting Program

ObjectiveSarcopenia is a risk factor for poor outcomes in older adults. Identification of plasma markers may facilitate screening of sarcopenia. We previously reported that creatinine-to-cystatin C ratio is a simple marker of muscle mass. To further assess the clinical relevance of the creatinine-to-cystatin C ratio, we investigated its association with myosteatosis and physical performance.DesignObservational study.Setting and ParticipantsCross-sectional analysis of the dataset obtained from a Japanese population consisting of 1468 older (≥60 years of age) community residents.MethodsThe mean attenuation values of the skeletal muscle calculated from computed tomography images of the midthigh were used as an index of myosteatosis, while the cross-sectional area of the muscle was used as a proxy for muscle mass. Physical performance was assessed by 1-leg standing time.ResultsCreatinine-to-cystatin C ratio was positively associated with the cross-sectional area of muscle fiber-rich muscles, while it showed an inverse association with fat-rich muscle areas, resulting in the positive association between creatinine-to-cystatin C ratio and the mean attenuation value of the skeletal muscle [creatinine-to-cystatin C ratio quartiles (Q), Q1: 47.4 ± 4.8, Q2: 48.9 ± 4.4, Q3: 49.8 ± 4.1, Q4: 50.9 ± 3.7, P < .001]. The results of the linear regression analysis adjusted for major covariates (including muscle cross-sectional area) identified creatinine-to-cystatin C ratio as an independent determinant of the mean attenuation value (Q1: reference, Q2: β = 0.07, P = .019, Q3: β = 0.11, P < .001, Q4: β = 0.16, P < .001). Low creatinine-to-cystatin C ratio was independently associated with 1-leg standing time, although the association was attenuated substantially by adjusting for skeletal muscle cross-sectional area and mean attenuation value.Conclusion and ImplicationsCreatinine-to-cystatin C ratio was associated with myosteatosis in older adults, independent of the muscle mass. Creatinine-to-cystatin C ratio may serve as a convenient marker of sarcopenia.     

中药肾复舒颗粒合用阿托品对肾衰大鼠残余肾VEGF和MVD的影响

目的观察中药肾复舒颗粒合用阿托品对肾衰大鼠残余肾组织血管内皮生长因子(VEGF)的表达和微血管密度(MVD)分布与肾损伤的影响。方法将5/6肾切除SD大鼠随机分为肾复舒治疗组、肾复舒+阿托品治疗组和模型组,并设假手术组为正常对照,术后1周开始给药,连续8周后处死动物。采血检测各组用药前后血尿素氮(BUN)、血肌酐(Cr)和尿蛋白的浓度变化;并取大鼠残余肾组织切片用HE染色和免疫组化法检测肾组织VEGF表达水平及MVD、肾小球硬化指数(GSI)、肾小管间质损伤指数(TIS)。用MVD与BUN、Cr、GSI、TIS和尿蛋白作相关分析。结果两治疗组肾组织VEGF、MVD表达比对照组明显增强;VEGF与MVD成正相关;MVD与血尿素、肌酐、GSI、TIS和尿蛋白成负相关(P<0.05);且肾复舒+阿托品组改变更为明显(P<0.05)。结论肾复舒和阿托品能加强VEGF在残余肾组织的表达,增加微血管密度;降低肾小球硬化和肾小管间质损伤程度。2种药物合用作用更为明显。