Introduction

Several factors, including diuretic use and sepsis, interfere with the fractional excretion of sodium, which is used to distinguish transient from persistent acute kidney injury (AKI). These factors do not affect the fractional excretion of urea (FeUrea). However, there are conflicting data on the diagnostic accuracy of FeUrea.

Methods

We conducted an observational, prospective, multicenter study at three ICUs in university hospitals. Unselected patients, except those with obstructive AKI, were admitted to the participating ICUs during a six-month period. Transient AKI was defined as AKI caused by renal hypoperfusion and reversal within three days. The results are reported as medians (interquartile ranges).

Results

A total of 203 patients were included. According to our definitions, 67 had no AKI, 54 had transient AKI and 82 had persistent AKI. FeUrea was 39% (28 to 40) in the no-AKI group, 41% (29 to 54) in the transient AKI group and 32% (22 to 51) in the persistent AKI group (P = 0.12). FeUrea was of little help in distinguishing transient AKI from persistent AKI, with the area under the receiver operating characteristic curve being 0.59 (95% confidence interval, 0.49 to 0.70; P = 0.06). Sensitivity was 63% and specificity was 54% with a cutoff of 35%. In the subgroup of patients receiving diuretics, the results were similar.

Conclusions

FeUrea may be of little help in distinguishing transient AKI from persistent AKI in critically ill patients, including those receiving diuretic therapy. Additional studies are needed to evaluate alternative markers or strategies to differentiate transient from persistent AKI.

Acute respiratory failure is a life-threatening complication in cancer patients. During neutropenia, patients are at high risk for bacterial pneumonia or invasive fungal infections, when neutropenia is prolonged. A high proportion of patients in whom neutropenia had been complicated by pneumonia will present with substantial respiratory deterioration during neutropenia recovery. Patients with fungal pneumonia and those receiving granulocyte colony-stimulating factor to shorten neutropenia duration may be at higher risk for this acute lung injury/acute respiratory distress syndrome during neutropenia recovery. Routine screening of patient's risk factors is crucial since first symptoms of acute respiratory distress syndrome may occur before biological leukocyte recovery.

Introduction

The purpose of this study was to assess the accuracy of N-terminal-pro-B-type natriuretic peptide (NT-proBNP) as a diagnostic tool to recognize acute respiratory failure of cardiac origin in an unselected cohort of critically ill patients.

Methods

We conducted a prospective observational study of medical ICU patients. NT-proBNP was measured at ICU admission, and diagnosis of cardiac dysfunction relied on the patient's clinical presentation and echocardiography.

Results

Of the 198 patients included in this study, 102 (51.5%) had evidence of cardiac dysfunction. Median NT-proBNP concentrations were 5,720 ng/L (1,430 to 15,698) and 854 ng/L (190 to 3,560) in patients with and without cardiac dysfunction, respectively (P < 0.0001). In addition, NT-proBNP concentrations were correlated with age (ρ = 0.43, P < 0.0001) and inversely correlated with creatinine clearance (ρ = -0.58, P < 0.0001). When evaluating the performance of NT-proBNP concentrations to detect cardiac dysfunction, the area under the receiver operating characteristic (ROC) curve was 0.76 (95% confidence interval (CI) 0.69 to 0.83). In addition, a stepwise logistic regression model revealed that NT-proBNP (odds ratio (OR) = 1.01 per 100 ng/L, 95% CI 1.002 to 1.02), electrocardiogram modifications (OR = 11.03, 95% CI 5.19 to 23.41), and severity assessed by organ system failure score (OR = 1.63 per point, 95% CI 1.17 to 2.41) adequately predicted cardiac dysfunction. The area under the ROC curve of this model was 0.83 (95% CI 0.77 to 0.90).

Conclusions

NT-proBNP measured at ICU admission might represent a useful marker to exclude cardiac dysfunction in critically ill patients.

Acute renal failure (ARF) in cancer patients is a dreadful complication that causes substantial morbidity and mortality. Moreover, ARF may preclude optimal cancer treatment by requiring a decrease in chemotherapy dosage or by contraindicating potentially curative treatment. The pathways leading to ARF in cancer patients are common to the development of ARF in other conditions. However, ARF may also develop due to etiologies arising from cancer treatment, such as nephrotoxic chemotherapy agents or the disease itself, including post-renal obstruction, compression or infiltration, and metabolic or immunological mechanisms. This article reviews specific renal disease in cancer patients, providing a comprehensive overview of the causes of ARF in this setting, such as treatment toxicity, acute renal failure in the setting of myeloma or bone marrow transplantation.