Diagnostic and prognostic stratification in the emergency department using urinary biomarkers of nephron damage: a multicenter prospective cohort study.

OBJECTIVES: This study aimed to determine the diagnostic and prognostic value of urinary biomarkers of intrinsic acute kidney injury (AKI) when patients were triaged in the emergency department. BACKGROUND: Intrinsic AKI is associated with nephron injury and results in poor clinical outcomes. Several urinary biomarkers have been proposed to detect and measure intrinsic AKI. METHODS: In a multicenter prospective cohort study, 5 urinary biomarkers (urinary neutrophil gelatinase-associated lipocalin, kidney injury molecule-1, urinary liver-type fatty acid binding protein, urinary interleukin-18, and cystatin C) were measured in 1,635 unselected emergency department patients at the time of hospital admission. We determined whether the biomarkers diagnosed intrinsic AKI and predicted adverse outcomes during hospitalization. RESULTS: All biomarkers were elevated in intrinsic AKI, but urinary neutrophil gelatinase-associated lipocalin was most useful (81% specificity, 68% sensitivity at a 104-ng/ml cutoff) and predictive of the severity and duration of AKI. Intrinsic AKI was strongly associated with adverse in-hospital outcomes. Urinary neutrophil gelatinase-associated lipocalin and urinary kidney injury molecule 1 predicted a composite outcome of dialysis initiation or death during hospitalization, and both improved the net risk classification compared with conventional assessments. These biomarkers also identified a substantial subpopulation with low serum creatinine at hospital admission, but who were at risk of adverse events. CONCLUSIONS: Urinary biomarkers of nephron damage enable prospective diagnostic and prognostic stratification in the emergency department.

The efficacy of a topical anesthetic gel in the relief of pain associated with localized alveolar osteitis.

PURPOSE: This prospective randomized clinical study assessed the efficacy of pain control for postextraction alveolar osteitis comparing the use of eugenol on a gauze strip versus a thermosetting gel containing 2.5% prilocaine and 2.5% lidocaine. PATIENTS AND METHODS: Thirty-five patients who presented with postextraction alveolar osteitis were randomly assigned to either a control group or test group. After irrigation of the extraction site with normal saline solution, the control patients were treated with eugenol on a gauze strip placed in the socket and the test patients were treated with the thermosetting gel placed directly into the socket. All patients were given a series of visual analog scales to record their pretreatment pain and post-treatment pain at 5, 10, and 15 minutes and then at 1-hour increments during waking hours for the next 48 hours. They were also given a prescription for an analgesic to use for breakthrough pain during the 48-hour period, if necessary, and instructed to record the dose and timing of any pain medication taken. All patients were seen for follow-up at 48 hours after treatment. RESULTS: The mean pretreatment pain score was 6.72 on a scale ranging from 1 to 10 for the eugenol group and 6.37 for the prilocaine-lidocaine group (SE, 0.46), and the 2 groups were not different (P = .62). In the immediate post-treatment period (0-15 minutes) the pain levels were significantly reduced in both groups (Ps < .001). However, the thermosetting gel produced a significantly greater reduction in pain (mean, 3.23; SE, 0.62) than the eugenol (mean, 4.83; SE, 0.43) (P = .022). Over the next 48 hours, the pain level was nominally less with the thermosetting gel, but this difference was not statistically significant (Ps = .2). CONCLUSION: Although the efficacy of the 2 treatments was not significantly different, the nominal superiority and ease of using the thermosetting gel warrant further investigation.

Sensitivity and specificity of a single emergency department measurement of urinary neutrophil gelatinase-associated lipocalin for diagnosing acute kidney injury.

BACKGROUND: A single serum creatinine measurement cannot distinguish acute kidney injury from chronic kidney disease or prerenal azotemia. OBJECTIVE: To test the sensitivity and specificity of a single measurement of urinary neutrophil gelatinase-associated lipocalin (NGAL) and other urinary proteins to detect acute kidney injury in a spectrum of patients. DESIGN: Prospective cohort study. SETTING: Emergency department of Columbia University Medical Center, New York, New York. PARTICIPANTS: 635 patients admitted to the hospital with acute kidney injury, prerenal azotemia, chronic kidney disease, or normal kidney function. MEASUREMENTS: Diagnosis of acute kidney injury was based on the RIFLE (risk, injury, failure, loss, and end-stage) criteria and assigned by researchers who were blinded to experimental measurements. Urinary NGAL was measured by immunoblot, N-acetyl-beta-d-glucosaminidase (NAG) by enzyme measurement, alpha1-microglobulin and alpha(1)-acid glycoprotein by immunonephelometry, and serum creatinine by Jaffe kinetic reaction. Experimental measurements were not available to treating physicians. RESULTS: Patients with acute kidney injury had a significantly elevated mean urinary NGAL level compared with the other kidney function groups (416 microg/g creatinine [SD, 387]; P = 0.001). At a cutoff value of 130 microg/g creatinine, sensitivity and specificity of NGAL for detecting acute injury were 0.900 (95% CI, 0.73 to 0.98) and 0.995 (CI, 0.990 to 1.00), respectively, and positive and negative likelihood ratios were 181.5 (CI, 58.33 to 564.71) and 0.10 (CI, 0.03 to 0.29); these values were superior to those for NAG, alpha1-microglobulin, alpha1-acid glycoprotein, fractional excretion of sodium, and serum creatinine. In multiple logistic regression, urinary NGAL level was highly predictive of clinical outcomes, including nephrology consultation, dialysis, and admission to the intensive care unit (odds ratio, 24.71 [CI, 7.69 to 79.42]). LIMITATIONS: All patients came from a single center. Few kidney biopsies were performed. CONCLUSION: A single measurement of urinary NGAL helps to distinguish acute injury from normal function, prerenal azotemia, and chronic kidney disease and predicts poor inpatient outcomes.

Value of definitive diagnostic testing in the evaluation of patients presenting to the emergency department with chest pain.

The optimal diagnostic evaluation of patients presenting to the emergency department (ED) with chest pain but without myocardial infarction or unstable angina is controversial. We performed a prospective, nonrandomized, observational study of 1,195 consecutive patients presenting to the ED with chest pain but who had normal or nondiagnostic electrocardiograms and negative cardiac biomarkers. Patients (mean +/- SD age 61 +/- 15 years; 55% women) were admitted to the hospital and a standard protocol for evaluation and treatment was suggested. The use of stress myocardial perfusion imaging (MPI) or cardiac catheterization during their index hospitalization, and the 3-month incidence of coronary angiography, percutaneous cardiac intervention, coronary artery bypass surgery, re-presentation to our institution's ED for chest pain, myocardial infarction, or death were followed. Five hundred nine of 1,195 patients (43%) underwent provocative stress MPI during their index hospitalization; 37% had perfusion defects (predominantly ischemia). Fifty-six of 1,195 patients (4%) underwent cardiac catheterization without stress MPI for their primary diagnostic evaluation. Six hundred thirty of 1,195 patients (53%) had neither MPI or cardiac catheterization during their index hospitalization. During the 3-month follow-up period, patients with a normal stress perfusion study during their index hospitalization had fewer return visits (4%) compared with patients with abnormal perfusion studies (19%), those who underwent catheterization directly (16%), or patients with no initial diagnostic evaluation (15%) (p <0.001). In addition, patients who had a diagnostic evaluation during their index hospitalization had a lower incidence of either acute myocardial infarction (0.9% vs 2.1%) or death (0.4% vs 3.0%, p <0.001) in the 3-month follow-up period. Accordingly, we strongly advocate provocative stress MPI early after presentation for chest pain in all patients with risk factors for coronary artery disease.