Diagnostic performance of salivary urea nitrogen dipstick to detect and monitor acute kidney disease in patients with malaria

BACKGROUND: Acute kidney injury (AKI) is a common complication of malaria. In low resource settings, a lack of diagnostic tools and delayed treatment of malaria associated AKI lead to significant morbidity and mortality. The aim of this study was to assess the diagnostic performance of salivary urea nitrogen (SUN) dipstick to detect and monitor kidney disease [KD = AKI or acute kidney disease (AKD) without AKI] in malaria patients in Angola. METHODS: Patients 11–50 years old admitted with malaria at the Josina Machel (Maria-Pia) Hospital, Luanda, Angola, between 2nd March and 10th May 2016 were enrolled in this study. All participants had serum creatinine (sCr), blood urea nitrogen (BUN) and SUN dipstick tested at the time of recruitment and daily for up to 4 days. AKD without AKI refers to acute renal impairment which do not fulfilled the main criteria for AKI (increases in the baseline serum creatinine and/or decreases in urine output) according defined by the kidney disease improving global outcomes (KDIGO) guideline. RESULTS: Eight-six patients were admitted with malaria diagnosis (mean age 21.5 ± 9.4 years, 71% male) and 27 (32%) were diagnosed with KD. The mean (± SD) sCr and BUN of the KD group at admission (day 0) were 5.38 (± 5.42) and 99.4 (± 61.9) mg/dL, respectively. Three (3.5%) patients underwent haemodialysis and eight (9.3%) died within the first 4 days of hospital admission [5 (62.5%) with KD; 3 (37.5%) without kidney disease; p = 0.047]. The SUN threshold for KD diagnosis was tested pad #5 (SUN > 54 mg/dL). At this threshold, the SUN dipstick had a sensitivity of 67% and specificity of 98% to diagnose KD. The area under the receiver operating characteristics curve (ROC) for KD diagnosis on admission was 0.88 (95% CI 0.79–0.96). The SUN dipstick was most accurate at higher levels of BUN. CONCLUSION: The SUN dipstick had reasonable sensitivity and excellent specificity when used to diagnose KD in a cohort of patients with malaria in a resource-limited setting. Given the severity of presenting illness and kidney injury, the SUN dipstick diagnostic threshold was high (test pad #5). SUN may be used to detect AKI in patients with malaria in low resources settings, thus facilitating earlier access to adequate treatment, which may improve survival

A Salivary Urea Nitrogen Dipstick to Detect Obstetric-Related Acute Kidney Disease in Malawi

Introduction: Obstetric-related acute kidney injury (AKI) is associated with adverse outcomes for mother and fetus, particularly in low-income countries. However, laboratory-independent tools to facilitate diagnosis are lacking. We assessed the diagnostic performance of a salivary urea nitrogen (SUN) dipstick to detect obstetric-related acute kidney disease in Malawi. / Methods: Women at high risk for AKI admitted to an obstetric unit in Blantyre, Malawi, were recruited between 21 September and 11 December 2015. Patients underwent serum creatinine (SCr) testing alongside measurement of SUN using a dipstick on admission, and every 48 hours thereafter if evidence of kidney disease was found. / Results: A total of 301 patients were included (mean age 25.9 years, 11% HIV positive). Of the patients, 23 (7.6%) had AKI, stage 1 in 47.8%, most commonly due to preeclampsia/eclampsia. Mean presenting SCr values were 108.8 ± 21.8 μmol/l (1.23 ± 0.25 mg/dl), 118 ± 34.45 μmol/l (1.33 ± 0.39 mg/dl), and 136.1 ± 30.4 μmol/l (1.54 ± 0.34 mg/dl) in AKI stages 1 to 3 respectively. SUN > 14 mg/dl had a sensitivity of 12.82% and a specificity of 97.33% to detect acute kidney disease; the area under the receiver operating characteristic curve was 0.551. In patients with normal SUN on admission, perinatal mortality was 11.8%, and was 25.0% if SUN was?> 14 mg/dl (P = 0.18). / Conclusion: The SUN dipstick was specific but insensitive when used to diagnose obstetric-related AKI. Limited biochemical derangement and low salivary urea concentrations due to physiological changes in pregnancy, as opposed to a technical limitation of the dipstick itself, are the likely reason for the lack of sensitivity in this study

Diagnostic Performance of a Saliva Urea Nitrogen Dipstick to Detect Kidney Disease in Malawi

Introduction: Kidney disease (KD), including acute kidney injury, is common, severe and leads to significant mortality in the developing world. However, simple tools to facilitate diagnosis and guide treatment are lacking. We studied the diagnostic performance of saliva urea nitrogen (SUN) measured by dipstick to diagnose KD in a low-resource setting. Methods: Medical admissions to a tertiary hospital in Malawi had serum creatinine tested at presentation; SUN was measured using a dipstick. Patients with serum creatinine above normal range underwent serial measurements of SUN and blood urea nitrogen for up to 7 days. Hospital outcome was recorded in all patients. Results: A total of 742 patients were included (age 41 ± 17·3 years, 56.1% male); 146 (19.7%) had KD, including 114 (15.4%) with acute kidney injury. SUN >14 mg/dl had a sensitivity of 0.72 and a specificity of 0.87 to diagnose KD; specificity increased to 0.97 when SUN levels were combined with self-reported urine output. The diagnostic performance of SUN was comparable with the one of blood urea nitrogen (SUN area under curve, 0.82; 95% confidence interval, 0.78–0.87; blood urea nitrogen area under curve, 0.82; 95% confidence interval, 0.59–1.0). SUN >14 mg/dl on admission was an independent predictor of all-cause mortality (hazard ratio = 2.43 [95% confidence interval, 1.63–3.62]). Discussion: SUN measured by dipstick can be used to identify patients with KD in a low-resource setting. SUN is an independent predictor of mortality in this population

Performance of the CMS High Granularity Calorimeter prototype to charged pion beams of 20−-300 GeV/c

The upgrade of the CMS experiment for the high luminosity operation of the LHC comprises the replacement of the current endcap calorimeter by a high granularity sampling calorimeter (HGCAL). The electromagnetic section of the HGCAL is based on silicon sensors interspersed between lead and copper (or copper tungsten) absorbers. The hadronic section uses layers of stainless steel as an absorbing medium and silicon sensors as an active medium in the regions of high radiation exposure, and scintillator tiles directly readout by silicon photomultipliers in the remaining regions. As part of the development of the detector and its readout electronic components, a section of a silicon-based HGCAL prototype detector along with a section of the CALICE AHCAL prototype was exposed to muons, electrons and charged pions in beam test experiments at the H2 beamline at the CERN SPS in October 2018. The AHCAL uses the same technology as foreseen for the HGCAL but with much finer longitudinal segmentation. The performance of the calorimeters in terms of energy response and resolution, longitudinal and transverse shower profiles is studied using negatively charged pions, and is compared to GEANT4 predictions. This is the first report summarizing results of hadronic showers measured by the HGCAL prototype using beam test data.Comment: To be submitted to JINS

Particle identification using Boosted Decision Trees in the Semi-Digital Hadronic Calorimeter prototype

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