21090242
Dipstick proteinuria: can it guide hypertension management?
Recent guidelines call for lower blood pressure targets in patients with proteinuria of 1 g/d or greater. Dipstick test for proteinuria is widely available, but no information on its sensitivity or specificity is available when implementing current guidelines. To determine performance characteristics of dipstick proteinuria, we studied 332 patients attending a Veterans Administration renal clinic who underwent simultaneous measurement of urine protein and creatinine, as well as automated urinalysis with a dipstick graded from 0 to 4+ with a machine reader. There was increasing severity of proteinuria with each increment in dipstick result. When the spot urine protein-creatinine ratio was less than 1, a lower specific gravity was associated with greater severity of proteinuria. Areas under the receiver operating characteristic curve for 1 and 3 g protein/g creatinine were 0.945 and 0.905, respectively. This attests to the excellent performance of the urine dipstick. The likelihood of having a protein-creatinine ratio of 1 or greater was 7% when urine dipstick protein value was 1+ or 2+, 62% when dipstick protein value was 3+, and 92% when dipstick protein value was 4+. Thus, dipstick proteinuria assessed by an automated reader remains a useful test to predict the severity of proteinuria and can be used to guide therapy. A cutoff dipstick proteinuria value of 3+ has the best combination of sensitivity and specificity (96% and 87%, respectively) in predicting a protein-creatinine ratio of 1 or greater and a cutoff value of 4+ in predicting a protein-creatinine ratio of 3 or greater (sensitivity, 94%; specificity, 83%). These results suggest that patients with 3+ or greater proteinuria should not only trigger appropriate evaluation of proteinuria, but also have mean arterial pressures targeted to less than 92 mm Hg.
11453581
Proinflammatory effects of oxidative stress in chronic kidney disease: role of additional angiotensin II blockade.
Oxidative stress plays an important role in causing progressive chronic kidney disease (CKD). We examined the influence of add-on ANG II receptor blockade administered as losartan (50 mg/day for 1 mo) on oxidative stress and proinflammatory state of the kidney in patients with CKD. All subjects were taking an angiotensin-converting enzyme inhibitor plus other antihypertensive agents. Oxidative stress to lipids and proteins was measured by an HPLC assay for malondialdehyde (MDA) and carbonyl concentration, respectively. Urinary inflammation was measured by monocyte chemotactic protein-1 (MCP-1) excretion rate. The etiology of CKD was type 2 diabetes mellitus in 12 and glomerulonephritis in 4 patients. There was no change in proteinuria or 24-h ambulatory blood pressure (BP) with add-on ANG II receptor blockade with losartan therapy. Before losartan therapy, urinary protein and albumin oxidation were 99 and 71% higher, respectively, compared with in plasma (P < 0.05). There was a 35% reduction in urinary oxidized albumin with add-on losartan therapy (P = 0.036). Urinary and plasma MDA were elevated compared with age-matched controls. Urinary MDA was significantly reduced from 4.75 +/- 3.23 to 3.39 +/- 2.17 micromol/g creatinine with add-on losartan therapy. However, plasma MDA or oxidized proteins did not change in response to additional ANG II blockade. A good correlation was seen between the change in urinary oxidized albumin and MCP-1 levels (r = 0.61, P = 0.012). These data demonstrate that oxidative damage to urinary protein and lipids can be reduced with additional ANG II receptor blockade, independently of reductions in proteinuria or BP. Urinary measurements of markers of oxidative damage to lipids and proteins appear to be more sensitive than plasma measurements in patients with CKD. The significant association of the change in urinary MCP-1 with a reduction in oxidative stress supports the role of the redox state in the kidney with renal fibrosis and progressive kidney damage.
36005104
Volume Overload in Dialysis: The Elephant in the Room, No One Can See
interests of the authors. However, considering the totality of the evidence, I am less convinced that this marker is superior to other volume markers. First, there are few head-to-head studies comparing BIA to other established markers of volume. Second, there is no range that defines ‘normal’. Unlike blood pressure (BP) or cholesterol, there is no target that has been established. The normal values are obtained from healthy subjects whose body composition differs substantially from those on dialysis. Extrapolating from healthy subjects to those with ESRD on hemodialysis does not appear scientifically valid. Third, there is no study to my knowledge that demonstrates convincingly that compared to probing dry weight without BIA, BIA-guided dry weight reduction results in improved outcomes. Most data provided to support the use of BIA are associative and observational. A large amount of observational data does not prove causation. We therefore have to be cautious in interpreting these data as ‘strongly indicative of fluid overload’. Nearly all markers of volemia suffer from the same shortcomings. These shortcomings include lack of normative data, and data being largely observational and associative in nature. As an example, several observational studies suggest that B-type natriuretic peptide (BNP), NT-proBNP or other natriuretic peptides are associated with volume state among people with ESRD on dialysis [2–10] . However, only one study has been reported to date that relates the change in BNP to an intervention of probing dry weight [11] . In this study, a direct relationship existed at baseline between BNP and interdialytic ambulatory BP. Since interdialytic ambulatory BP is reVolume overload is the invisible threat to the health of dialysis patients. Currently, Medicare incentivizes the measurement of the dose of dialysis (urea reduction ratio) but has no measure of volume. Perhaps this is because the few who can recognize the epidemic nature of volume excess cannot agree on how to define it. Whereas, some have proposed interdialytic weight gain (IDWG) as a marker of volume, the in-depth review of Hecking et al. [1] quite clearly and importantly makes the distinction that IDWG should not be confused with hypervolemia. One has to wonder how IDWG got confused with dry weight in the first place. It appears that epidemiologists decided to use IDWG as a proxy of dry weight because of its ready availability in large databases. IDWG is a marker that is convenient; it can be measured easily and it can be related to outcomes such as all-cause mortality. This analysis was performed and a relationship emerged between IDWG and all-cause mortality. But establishing a relationship between IDWG and mortality does not establish causality. It could be numerous other factors, measured and unmeasured, associated with IDWG which may be causally related to mortality. Factors such as missing or cutting short dialysis, not taking medications as prescribed, and consuming a diet rich in phosphorus and potassium are some confounding factors that may also be associated with IDWG but may be more plausibly related to mortality. The authors discuss several markers of volume excess. Although several exist, one marker, bioimpedance analysis (BIA), is discussed in great detail. This is understandable given both the academic and intellectual property Published online: July 6, 2013 Nephrology American Journal of
24249726
Regulation of circadian blood pressure: from mice to astronauts.
PURPOSE OF REVIEW
Circadian variation is commonly seen in healthy people; aberration in these biological rhythms is an early sign of disease. Impaired circadian variation of blood pressure (BP) has been shown to be associated with greater target organ damage and with an elevated risk of cardiovascular events independent of the BP load. The purpose of this review is to examine the physiology of circadian BP variation and propose a tripartite model that explains the regulation of circadian BP.


RECENT FINDINGS
The time-keeper in mammals resides centrally in the suprachiasmatic nucleus. Apart from this central clock, molecular clocks exist in most peripheral tissues including vascular tissue and the kidney. These molecular clocks regulate sodium balance, sympathetic function and vascular tone. A physiological model is proposed that integrates our understanding of molecular clocks in mice with the circadian BP variation among humans. The master regulator in this proposed model is the sleep-activity cycle. The equivalents of peripheral clocks are endothelial and adrenergic functions. Thus, in the proposed model, the variation in circadian BP is dependent upon three major factors: physical activity, autonomic function, and sodium sensitivity.


SUMMARY
The integrated consideration of physical activity, autonomic function, and sodium sensitivity appears to explain the physiology of circadian BP variation and the pathophysiology of disrupted BP rhythms in various conditions and disease states. Our understanding of molecular clocks in mice may help to explain the provenance of blunted circadian BP variation even among astronauts.
22176722
Alar web in cleft lip nose deformity: study in adult unilateral clefts.
BACKGROUND
The correction of alar webbing in unilateral cleft lip nose deformity is challenging because of progressive distortions in the alar web region during the period of growth. Alar webbing is a persistent universal deformity in both the primary and secondary cleft lip noses. The purpose of this article is to study the alar web deformity in adult patients with unilateral cleft lip noses.


METHODS
Twenty-five patients aged 13 years and older presenting with unilateral cleft nasal deformity were included. Preoperative and postoperative measurements of the nose, along with detailed intraoperative recording of the deformed anatomy, were done. Preoperative magnetic resonance imaging was also done in selected cases. Transcolumellar open rhinoplasty was performed in all the cases, and nasal septal straightening with centralization was done. Cleft alar base augmentation was done using bone graft to restore symmetry of the nasal tripod. Both the cleft and noncleft alar cartilages were extensively mobilized from the skin and mucosal sides. The overgrown and caudally slumped cleft-side alar cartilage was resected caudally and was then resuspended in a symmetrical position with the noncleft alar cartilage. A midline-strut septal cartilage extension graft was used to restore the tip aesthetics. The skin overlying the alar web was in-rolled after semilunar cartilage resection, and skin excision was also done to restore symmetry with the opposite vestibule. The remaining secondary cleft nasal and lip deformities were corrected depending upon the specific presenting pathologic abnormality.


RESULTS
The cleft alar cartilage was found to be caudally displaced in all the cases. The caudal border of the lateral crus was prolapsing in the cavity of the vestibule on the superomedial aspect and was tenting the skin in the area of the weak triangle, producing the characteristic alar web deformity. In the study group, the maximum width of the cleft alar cartilage at the level of the lateral crus was increased by approximately 4 mm when compared with the noncleft alar cartilage. The before- and after-rhinoplasty surgery results were objectively assessed using a patient, surgeon, and independent observer survey. The cosmetic result of the nasal tip complex was found to be very good and good (90%), satisfactory (5%), and poor (5%) in patients.


CONCLUSIONS
The alar web in unilateral cleft lip nose deformity is the result of caudal overgrowth and migration of the alar cartilage. The caudal edge of the prolapsed lateral crus overhangs the cleft-side nasal aperture on its superomedial aspect, producing this deformity. Satisfactory correction of this deformity should envisage caudal resection and repositioning of the dislocated alar cartilage along with caudal resection of the lateral crus with in-rolling of the skin after resection to achieve symmetric results in unilateral cleft lip rhinoplasty.
191311
Assessment of iothalamate plasma clearance: duration of study affects quality of GFR.
BACKGROUND AND OBJECTIVES
Measurement of GFR is important for the management of chronic kidney disease (CKD). Although bolus administration of radiocontrast agents is commonly used to measure GFR, the optimal duration of sampling to assess their plasma clearance is unknown. The purpose of this study was to evaluate whether the duration of plasma sampling influences precision and estimation of GFR.


DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS
GFR was measured by sampling plasma 12 times over 5 h in 56 patients with CKD (mean age 64 yr, 98% men, 79% Caucasian, 34% diabetics, estimated GFR 31.8 +/- 14.2 ml/min/1.73 m(2)). In a subset of 12 patients we measured GFR by sampling plasma 17 times over 10 h.


RESULTS
Short sampling intervals considerably overestimated GFR measured using total plasma iothalamate clearance, especially in larger patients. In the higher estimated GFR group (>30 ml/min/1.73 m(2)), the 5-h GFR was 17% higher and 2-h GFR 54% higher compared with the 10-h GFR, which averaged 40.3 ml/min/1.73 m(2). In the lower estimated GFR group (<30 ml/min/1.73 m(2)), the 5-h GFR was 36% higher and 2-h GFR 126% higher compared with the 10-h GFR, which averaged 22.2 ml/min/1.73 m(2). Short sampling duration also reduced the precision of the estimated GFR from 1.67% for 10-h GFR, to 3.48% for 5-h GFR, and to 7.07% for 2-h GFR.


CONCLUSIONS
GFR measured over a longer duration with multiple plasma samples spanning the distribution and elimination phases may improve precision and provide a better measure of renal function.
17440391
Allergic Bronchopulmonary Aspergillosis with Aspergilloma: An Immunologically Severe Disease with Poor Outcome
Background and AimsThe association between allergic bronchopulmonary aspergillosis (ABPA) and aspergilloma has been proposed as a severe form of ABPA. However, this conclusion is based on single-patient case reports. In this study, we describe the clinical details and immunological findings of this association and compare patients of ABPA with aspergilloma and those without.MethodsThis is a retrospective analysis of data of patients with ABPA managed in the Chest Clinic. We compared the clinical, radiological and immunological profile of patients with ABPA and central bronchiectasis, with and without the presence of aspergilloma on HRCT scan.ResultsThere were 98 men and 81 women with a mean (SD) age of 33.6 (12.2) years. Eight patients were diagnosed to have aspergilloma. Sputum cultures grew Aspergillus fumigatus in all these eight patients. The aspergilloma was solitary in six patients, and two each in two patients. Patients with aspergilloma had higher IgE levels (both total and A. fumigatus specific) than those without aspergilloma. Bronchiectasis was also more extensive in patients with aspergilloma. Overall, 70 % of the ABPA patients experienced relapse during the median (interquartile range) follow-up of 27 (19–39) months. The number of relapses was significantly higher in patients with aspergilloma (p = 0.0001). On a multivariate linear regression analysis, high-attenuation mucus and aspergilloma were independent predictors of relapse frequency.ConclusionsThe concurrent presentation of ABPA and aspergilloma is associated with an immunologically severe disease and risk of recurrent relapses.
25550116
Noninvasive estimation of clinically asymptomatic pulmonary hypertension in idiopathic pulmonary fibrosis.
OBJECTIVES
To determine the prevalence of pulmonary hypertension in patients with idiopathic pulmonary fibrosis (IPF) by noninvasive methods.


PATIENTS AND METHODS
Twenty seven patients with IPF attending the Chest Clinic over a period of one-and-a-half-years underwent echocardiography for evidence of pulmonary hypertension, which was defined as pulmonary artery systolic pressure > or = 40 mmHg by Doppler echocardiography, or pulmonary acceleration time < or = 100 milliseconds or two-dimensional echocardiographic findings of right ventricular hypertrophy or overload.


RESULTS
Two patients with clinical evidence of pulmonary hypertension were excluded from analysis. Their mean age (n = 25) was 53.8 years. The mean duration of symptoms before presentation was 2.1 years. Pulmonary hypertension was diagnosed by echocardiography in nine of the 25 patients (36%). There was a statistically significant difference between the duration of illness, arterial oxygen tension (PaO2) levels and forced vital capacity in patients with pulmonary hypertension than in those without pulmonary hypertension. Logistic regression analysis showed a significant association between the duration of illness, decreasing forced vital capacity and hypoxemia with the development of pulmonary hypertension.


CONCLUSIONS
Echocardiography detects pulmonary hypertension in clinically asymptomatic individuals, and should be used routinely for the diagnosis of pulmonary hypertension in patients with IPF.
16330243
Diagnostic Performance of Various Tests and Criteria Employed in Allergic Bronchopulmonary Aspergillosis: A Latent Class Analysis
Aim The efficiency of various investigations and diagnostic criteria used in diagnosis of allergic bronchopulmonary aspergillosis (ABPA) remain unknown, primarily because of the lack of a gold standard. Latent class analysis (LCA) can provide estimates of sensitivity and specificity in absence of gold standard. Herein, we report the performance of various investigations and criteria employed in diagnosis of ABPA. Methods Consecutive subjects with asthma underwent all the following investigations Aspergillus skin test, IgE levels (total and A.fumigatus specific), Aspergillus precipitins, eosinophil count, chest radiograph, and high-resolution computed tomography (HRCT) of the chest. We used LCA to estimate the performance of various diagnostic tests and criteria in identification of ABPA. Results There were 372 asthmatics with a mean age of 35.9 years. The prevalence of Aspergillus sensitization was 53.2%. The sensitivity and specificity of various tests were Aspergillus skin test positivity (94.7%, 79.7%); IgE levels>1000 IU/mL (97.1%, 37.7%); A.fumigatus specific IgE levels>0.35 kUA/L (100%, 69.3%); Aspergillus precipitins (42.7%, 97.1%); eosinophil count>1000 cells/µL (29.5%, 93.1%); chest radiographic opacities (36.1%, 92.5%); bronchiectasis (91.9%, 80.9%); and, high-attenuation mucus (39.7%, 100%). The most accurate criteria was the Patterson criteria using six components followed by the Agarwal criteria. However, there was substantial decline in accuracy of the Patterson criteria if components of the criteria were either increased or decreased from six. Conclusions A.fumigatus specific IgE levels and high-attenuation mucus were found to be the most sensitive and specific test respectively in diagnosis of ABPA. The Patterson criteria remain the best diagnostic criteria however they have good veridicality only if six criteria are used.
25850480
Aspergillus hypersensitivity in patients with chronic obstructive pulmonary disease: COPD as a risk factor for ABPA?
Allergic bronchopulmonary aspergillosis (ABPA) is a pulmonary disorder caused by hypersensitivity to Aspergillus fumigatus which primarily complicates the course of asthma and cystic fibrosis. There is a theoretical possibility that patients with chronic obstructive pulmonary disease (COPD) can also develop Aspergillus hypersensitivity (AH) and/or ABPA. The aim of this prospective case-control study conducted in the Chest Clinic was to evaluate the prevalence of AH/ABPA in patients with COPD. Two hundred subjects with COPD (17, 62, 74, 47; GOLD guidelines stages I–IV respectively) and 100 healthy volunteers were screened with an Aspergillus skin test. Patients were said to have AH if they demonstrated immediate cutaneous hyperreactivity to A. fumigatus antigen and those with positive responses were further investigated for ABPA. Of this patient population there were 179 (89.5%) males and 21 (10.5%) females with a mean age of 57.1 in the COPD arm and 88 males and 12 females with a mean age of 52.3 in the control arm. AH was found in 17 (8.5%) patients with COPD as compared to none in the control group. Two (1.0%) COPD patients fulfilled the serologic criteria for the diagnosis of ABPA. On univariate analysis, age of the patient, duration of COPD, smoking index and the COPD severity did not predict the occurrence of AH. On the basis of this study we concluded that AH/ABPA can occur in patients with COPD, and it is probable that COPD could be a predisposing factor for AH/ABPA. The clinical significance of AH and ABPA in COPD remains unclear.
5382028
Structural insight into mechanism and diverse substrate selection strategy of L-ribulokinase.
The araBAD operon encodes three different enzymes required for catabolism of L-arabinose, which is one of the most abundant monosaccharides in nature. L-ribulokinase, encoded by the araB gene, catalyzes conversion of L-ribulose to L-ribulose-5-phosphate, the second step in the catabolic pathway. Unlike other kinases, ribulokinase exhibits diversity in substrate selectivity and catalyzes phosphorylation of all four 2-ketopentose sugars with comparable k(cat) values. To understand ribulokinase recognition and phosphorylation of a diverse set of substrates, we have determined the X-ray structure of ribulokinase from Bacillus halodurans bound to L-ribulose and investigated its substrate and ATP co-factor binding properties. The polypeptide chain is folded into two domains, one small and the other large, with a deep cleft in between. By analogy with related sugar kinases, we identified (447)GGLPQK(452) as the ATP-binding motif within the smaller domain. L-ribulose binds in the cleft between the two domains via hydrogen bonds with the side chains of highly conserved Trp126, Lys208, Asp274, and Glu329 and the main chain nitrogen of Ala96. The interaction of L-ribulokinase with L-ribulose reveals versatile structural features that help explain recognition of various 2-ketopentose substrates and competitive inhibition by L-erythrulose. Comparison of our structure to that of the structures of other sugar kinases revealed conformational variations that suggest domain-domain closure movements are responsible for establishing the observed active site environment.