Bogusław Poniatowski

Neutrophil gelatinase-associated lipocalin is a new and sensitive marker of kidney function in chronic kidney disease patients and renal allograft recipients.

BACKGROUND/AIMS Few biomarkers exist to monitor chronic kidney disease (CKD). Neutrophil gelatinase-associated lipocalin (NGAL), a member of lipocalin family, has recently been proven useful to quantitate CKD. The aim of the study was to assess whether NGAL could represent a novel, sensitive marker of kidney function in adult patients with CKD and in kidney transplant recipients. METHODS We studied possible relations between serum NGAL, creatinine, and estimated glomerular filtration rate (eGFR) in 80 nondiabetic patients with CKD stages 2 to 4; 80 nondiabetic kidney transplant recipients on a calcineurin inhibitor mycophenolate mofetil, or azathioprine as well as prednisone and in healthy volunteers (n = 32, mean age 50 years). RESULTS Serum NGAL and creatinine values were significantly higher and eGFR significantly lower in kidney allograft recipients and patients with CKD compared with controls. NGAL rose gradually, reaching the higher value in stage 4 CKD. In univariate analysis serum NGAL was related to serum creatinine, hemoglobin, hematocrit, leukocyte count, and eGFR. Predictors of serum NGAL were creatinine and eGFR among patients with CKD. On univariate analysis serum NGAL was related to serum creatinine, urea, hemoglobin, hematocrit, white blood cell count, calcineurin concentration, eGFR, and albumin in kidney transplant recipients. On multiple regression analysis, predictors of NGAL were creatinine, calcineurin concentration, and high-sensitivity C-reactive protein. In healthy volunteers, serum NGAL correlated with age, serum creatinine, eGFR, and leukocyte count. CONCLUSION NGAL should be investigated as a potential early, sensitive marker of kidney impairment/injury, which might provide an additional accurate measure of kidney impairment in CKD and among transplant recipients, particularly at advanced stages.

Urinary and Serum Biomarkers after Cardiac Catheterization in Diabetic Patients with Stable Angina and without Severe Chronic Kidney Disease

Background/Aims. Different serum and urinary biomarkers have been recently proposed to serve as markers of acute kidney injury. We tested the hypothesis whether NGAL and other biomarkers could represent an early biomarker of contrast nephropathy (CIN) in diabetic patients with normal serum creatinine undergoing cardiac catheterization in comparison with non-diabetic patients. Methods. Serum, urinary NGAL, cystatin C, urinary kidney injury molecule-1 (KIM-1), interleukin-18 (IL-18), and liver-type fatty acid binding protein (L-FABP) were evaluated before and 2, 4, 8, 24, and 48 hours after cardiac catheterization using commercially available kits. Results. In both groups we found a significant rise in serum NGAL after 2, 4, and 8 hours, and in urinary NGAL and IL-18 after 4, 8, and 24 hours after cardiac catheterization. Serum cystatin C increased significantly 8 hours, reaching peak 24 hours after cardiac catheterization in both groups, and then decreased after 48 hours. L-FABP and KIM-1 increase significantly after 24 and 48 hours after cardiac catheterization. Conclusions. CIN was similarly prevalent in both diabetic and non-diabetic patients undergoing cardiac catheterization. NGAL seems to be a potential early marker for nephrotoxicity and predictor of contrast nephropathy. It is particularly important in the upcoming setting of short-time hospitalizations for cardiac catheterization.

Serum neutrophil gelatinase-associated lipocalin as a marker of renal function in patients with chronic heart failure and coronary artery disease.

Heart failure and chronic kidney disease share a number of risk factors and pathophysiological pathways. Renal insufficiency is common in patients with chronic heart failure (CHF). The aim of the study was to assess whether neutrophil gelatinase-associated lipocalin (NGAL) could represent a novel, sensitive marker of kidney function in adult patients with chronic heart failure and normal serum creatinine. The study was performed on 150 patients with chronic heart failure due to coronary artery disease. Serum and urinary NGAL as well as serum cystatin C were measured using commercially available kits. Serum NGAL was related, in univariate analysis, to serum creatinine, urinary NGAL, hemoglobin, hematocrit, leukocyte count, eGFR, cystatin C. Urinary NGAL correlated with age, hemoglobin, hematocrit, serum creatinine, eGFR. In multiple regression analysis predictors of serum NGAL were NYHA class, cystatin C, and eGFR. Taking into consideration the fact that the recent DOQI states that individuals with a reduced GFR is at greater risk for cardiovascular disease and cardiac deaths, precise evaluation of renal function is important in order to select the appropriate strategy to reduce the cardiovascular risk. NGAL should be investigated as a potential early and sensitive marker of kidney impairment/injury.

Serum Neutrophil Gelatinase-Associated Lipocalin as a Marker of Renal Function in Non-Diabetic Patients with Stage 2–4 Chronic Kidney Disease

The current Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines advocate creatinine-based equations for estimating GFR to identify patients with potential kidney disease and classify them into different stages due to the fact that serum creatinine is very insensitive to changes in the glomerular filtration rate. Very few biomarkers exist for monitoring chronic kidney disease. The aim of the study was to assess whether NGAL could represent a novel, sensitive marker of kidney function in adult patients with CKD. The study was performed on 92 non-diabetic patients with CKD stages 2–4. Serum and urinary NGAL as well as serum cystatin C were measured using commercially available kits. Serum NGAL was related, in univariate analysis, to serum creatinine, urinary NGAL, hemoglobin, hematocrit, leukocyte count, eGFR, and cystatin C. Urinary NGAL correlated with age, hemoglobin, hematocrit, serum creatinine, and eGFR. In multiple regression analysis, predictors of serum NGAL were creatinine (beta value = 0.97, p = 0.005), cystatin C (beta = 0.34, p = 0.01), and eGFR (beta value = 1.77, p = 0.001). In the healthy volunteers, serum NGAL correlated with age, serum creatinine, eGFR, leukocyte count, and cystatin C. Taking into consideration the fact that the recent DOQI (Dialysis Outcomes Quality Initiative) states that individuals with reduced GRF (glomerular filtration rate) are at greater risk for CVD and cardiac deaths, precise evaluation of renal function is important in order to select the appropriate strategy to reduce the cardiovascular risk. NGAL should be investigated as a potential early and sensitive marker of kidney impairment/injury.

NGAL (neutrophil gelatinase-associated lipocalin) and L-FABP after percutaneous coronary interventions due to unstable angina in patients with normal serum creatinine

PURPOSE The value of NGAL (neutrophil gelatinase-associated lipocalin) and L-FABP (liver-type fatty acid binding protein) has been highlighted as a novel biomarker of detection of acute renal failure in children after cardiac surgery. Interventional cardiologists are being asked more frequently to perform percutaneous coronary intervention (PCI) and contrast nephropathy is its potentially serious complication. We aimed to prospectively assess NGAL and L-FABP in patients with normal serum creatinine undergoing PCI due to unstable angina. MATERIAL AND METHODS We measured serum NGAL, urinary NGAL and L-FABP using commercially available kits before and after 2, 4, 12, 24 and 48 hours following PCI in 25 patients. RESULTS We found a significant rise in serum NGAL after 2 and 4 hours. Urinary NGAL and urinary L-FABP followed the same pattern. Both markers increased significantly after 4 hours and remained elevated up to 48 hours after PCI. Serum creatinine did not change significantly during the study period. CONCLUSIONS NGAL and L-FABP may represent a sensitive early biomarkers of renal impairment after PCI. Persistently increased urinary NGAL and L-FABP may suggest renotubular damage in this population.

Inadequate Blood Pressure Control in Most Kidney Transplant Recipients and Patients With Coronary Artery Disease With and Without Complications

BACKGROUND Hypertension is a widely accepted risk factor for coronary artery disease (CAD), chronic heart failure, and chronic kidney disease (CKD). In kidney transplant recipients, the prevalence of hypertension is 60% to 80%. OBJECTIVE To assess the prevalence of target blood pressure in 2 high-risk populations: patients with CAD and kidney allograft recipients. PATIENTS AND METHODS The study included 520 patients with CAD and 150 kidney allograft recipients. In the CAD population, 30% of patients had diabetes mellitus and 33% had CKD. In kidney allograft recipients, 52% had diabetes (15%) or CKD. Hypertension was diagnosed and treated in 72% of patients with CAD and 90% of kidney allograft recipients. In the CAD population without diabetes but with CKD, target blood pressure was achieved in 47% compared with 31% in the CKD population. Treatment included angiotensin-converting enzyme (ACE) inhibitors in 72% of patients, calcium channel blockers in 28%, diuretic agents in 27%, and beta-blockers in 89%. In allograft recipients, more than 60% required 3 or more hypotension agents. Only 40% demonstrated target blood pressure. In the latter group, the most commonly used hypotension agents were ACE inhibitors in 38%, calcium channel blockers in 84%, diuretic agents in 51%, beta-blockers in 68%, and alpha-blockers in 15%. CONCLUSION Both cohorts demonstrated a high prevalence of hypertension. Despite polytherapy, optimal blood pressure control was not achieved in most patients. Greater efforts should be expended to optimize blood pressure control, in particular in the presence of comorbidities. In transplant recipients, beta-blockers are widely used, whereas ACE inhibitors are used infrequently.

The Occurrence of blaCTX-M, blaSHV, and blaTEM Genes in Extended-Spectrum β-Lactamase-Positive Strains of Klebsiella pneumoniae, Escherichia coli, and Proteus mirabilis in Poland

Bacteria belonging to the Enterobacteriaceae family that produce extended-spectrum β-lactamase (ESBL) enzymes are important pathogens of infections. Increasing numbers of ESBL-producing bacterial strains exhibiting multidrug resistance have been observed. The aim of the study was to evaluate the prevalence of , , and genes among ESBL-producing Klebsiella pneumoniae, Escherichia coli, and Proteus mirabilis strains and to examine susceptibility to antibiotics of tested strains. In our study, thirty-six of the tested strains exhibited genes , , , and . Moreover, twelve ESBL-positive strains harbored genes , , , and , and the presence of a gene in twenty-five ESBL-positive strains was revealed. Among K. pneumoniae the multiple ESBL genotype composed of , and genes encoding particular ESBL variants was observed. Analysis of bacterial susceptibility to antibiotics revealed that, among β-lactam antibiotics, the most effective against E. coli strains was meropenem (100%), whereas K. pneumoniae were completely susceptible to ertapenem and meropenem (100%), and P. mirabilis strains were susceptible to ertapenem (91.7%). Moreover, among non-β-lactam antibiotics, gentamicin showed the highest activity to E. coli (91.7%) and ciprofloxacin the highest to K. pneumoniae (83.3%). P. mirabilis revealed the highest susceptibility to amikacin (66.7%).

Early and long-term prognosis of patients with coronary artery disease treated with percutaneous coronary interventions in 2005. Experience of single large-volume PCI center

PURPOSE The progress which has been made in interventional cardiology contributes to the gradual improvement of the results of CHD (coronary heart disease) therapy. The aim of the study was the assessment of early and long-term prognosis in all the patients with CHD treated invasively in one large-volume PCI center in 2005. MATERIAL AND METHODS 1390 consecutive patients with CHD treated with PCI in 2005 were included in the analysis. Patients with ST-elevation myocardial infarction (STEMI) accounted for 50% of cases, patients with stable angina (SA) amounted to 25%, and patients with non-ST elevation acute coronary syndromes (NSTE-ACS) constituted 25%. Mean follow-up was 738 (±237) days. RESULTS The highest mortality during the hospitalization was noted within the STEMI group(SA vs. NSTE-ACS vs. STEMI; 0% vs. 0.3% vs. 4.1%, respectively; p<0.001). The highest mortality during a 2-year follow-up was also observed in the STEMI group (SA vs. NSTE-ACS vs. STEMI, 6.3% vs. 8.5% vs. 13.8%, respectively; p<0.001). Multiple regression model showed that independent risk factors for death during the follow-up were: age, glycaemia at admission, heart rate, blood pressure, ejection fraction, STEMI, ineffective PCI (R=0.3613; F(10.131)=19.672; p<0.0001 for the model). CONCLUSIONS The highest relative increase of mortality after the discharge of patients with CHD undergoing PCI referred to the patients with NSTE-ACS. However, in the real life PCI practice STEMI patients have the worst hospital and long-term prognosis. Well recognized risk factors for death in patients with CHD are still of great importance in negative prognosis of patients undergoing PCI.

Expression of MexAB‐OprM efflux pump system and susceptibility to antibiotics of different Pseudomonas aeruginosa clones isolated from patients hospitalized in two intensive care units at University Hospital in Bialystok (northeastern Poland) between January 2002 and December 2009

We investigated the genetic similarities and expression of the MexAB‐OprM efflux pump system in different clones of multiresistant Pseudomonas aeruginosa strains collected from 2002 to 2009 at two intensive care units (ICU). Regulatory and structural genes mexB, mexR, and mexA were found in 99%, 98%, and 94% of tested strains, respectively. The presence of class 1 integron was found in 90% of the strains, while class 2 integron in only one strain (Psa506). Class 3 integron was not found in any of the tested strains. Among the eleven clones identified, only two clones, I and D, exhibited higher levels of mexB gene expression than the other clones. Clone I had the highest expression (FC = 10.36, p < 0.05). The results of our study indicated a high level of MexAB‐OprM pump expression in groups of strains isolated in the years 2008–2009 (FC = 12.92, p < 0.03) and 2002–2006 (FC = 5.14, p < 0.03). There were no statistically significant differences in resistance to all tested antibiotics among the various clones. The high level of antimicrobial resistance may have been due to the coexistence of different resistance mechanisms among the studied P. aeruginosa strains. However, this does not exclude the contribution of the MexAB‐OprM pump, particularly in resistance to meropenem and ciprofloxacin.

Distribution of AdeABC efflux system genes in genotypically diverse strains of clinical Acinetobacter baumannii

Acinetobacter baumannii has emerged as a highly problematic hospital-associated pathogen. Different mechanisms contribute to the formation of multidrug resistance in A. baumannii, including the AdeABC efflux system. Distribution of the structural and regulatory genes encoding the AdeABC efflux system among genetically diverse clinical A. baumannii strains was achieved by using PCR and pulsed-field gel electrophoresis techniques. The distribution of adeABRS genes is extremely high among our A. baumannii strains, except the adeC gene. We have observed a large proportion of strains presenting multidrug-resistance phenotype for several years. The efflux pump could be an important mechanism in these strains in resistance to antibiotics.