Elevated Blood Urea Nitrogen Concentration Research Articles

Ethnic disparities in bidirectional causal effects between serum uric acid concentrations and kidney function: Trans-ethnic Mendelian randomization study

IntroductionResearchers have investigated the causal effect between serum uric acid (SUA) concentrations and kidney function for decades, but studies produced inconsistent results. This study aimed to clarify the bidirectional causal effects between SUA concentrations and kidney function and to explore the potential ethnic disparities by conducting a trans-ethnic Mendelian randomization study in European, African, and Asian ancestries. Materials and methodsThe summary-level data for this study were obtained from the Global Urate Genetics Consortium, CKDGen Consortium, UK Biobank, and Japan Biobank for different outcomes and exposures, respectively. The traits of kidney function were estimated glomerular filtration rate from serum creatinine (eGFRcr), estimated glomerular filtration rate from cystatin C (eGFRcys), and blood urea nitrogen (BUN). Using the multiplicative random-effects inverse variance weighting mode, our primary analysis produced robust results despite heterogeneity. Additionally, we performed the Mendelian randomization pleiotropy residual sum and outlier test to eliminate the horizontal pleiotropy and obtain accurate results. ResultsOur findings revealed that elevated SUA concentrations had causal effects on declined eGFRcys, BUN, and a diagnosis of chronic kidney disease in European ancestries and eGFRcr in Asian ancestries. Additionally, the causal effects of declined eGFRcr and elevated BUN concentrations on elevated SUA concentrations were observed in both European and Asian ancestries. However, no bidirectional causal effect was found between SUA concentrations and eGFRcr among African ancestries. ConclusionsThis trans-ethnic Mendelian randomization study confirmed the bidirectional causal effects between SUA concentrations and kidney function and highlighted the importance of considering ethnic disparities in clinical treatments.

Predictors exploration of abnormal brain magnetic resonance versus normal brain computed tomography imaging in acute carbon monoxide poisoning

Acute brain lesions observed on magnetic resonance imaging (MRI) performed during acute-phase carbon monoxide (CO) poisoning were associated with patient prognosis. However, it may be difficult in critically ill patients because of the long examination time and for patients who have economical limitations due to the high price. The purpose of this study was to identify predictive factors for abnormal brain lesions on MRI in cases of normal brain findings on brain computed tomography (CT) in acute CO poisoning patients. This study was retrospectively analyzed at the tertiary emergency medical center located in Gyeonggi-do, Korea by prospectively collecting CO poisoning registry. From August 2016 to August 2019, 287 patients visited the hospital due to CO poisoning. Exclusion criteria included age under 18 years, being discharged against medical advice, no initial MRI data, no initial CT data, and having abnormal lesions on brain CT. Of the 103 patients included in the final study, the median age was 39 years old; 35 (34.0%) were male and 74 (71.8%) were intentionally exposed to CO. 27 (26.2%) patients had abnormal MRI findings. Based on multivariable analysis, elevated blood urea nitrogen (BUN) concentration (odds ratio, 1.165; 95% confidence interval, 1.037–1.308; p = 0.01) showed a significant association with abnormal MRI findings. The area under the curve was 0.753 (95% confidence interval, 0.636–0.869) in the receiver operating characteristic curve of BUN concentration for abnormal brain MRI presentations. Brain injury may be detected on brain MRI in acute CO poisoning patients even there was a normal brain CT scan. Our study revealed that elevated BUN concentration may be significantly correlated with abnormal MRI findings.

Clinical, microbiological and histological findings in lambs affected by ‘salivary abomasum disease’

‘Salivary abomasum disease’ is a common syndrome in Greece affecting lambs and kids from three to 17 days of age. In this case series, we present clinical and laboratory findings...

Elevated serum amylase and lipase in pediatric diabetic ketoacidosis*

Pancreatic enzyme concentrations are frequently elevated in children with diabetic ketoacidosis (DKA). We sought to determine the clinical and biochemical characteristics associated with patients with these elevations. Our hypothesis was that pancreatic enzyme elevations would be associated with biochemical markers of hypoperfusion. Prospective cohort study. Three university-affiliated children's hospitals. We collected data on consecutive children <18 yrs of age hospitalized with the diagnosis of DKA. Serum electrolyte and lactate concentrations and venous pH and Pco2 were measured every 3 hrs from hours 0 to 12 and then every 6 hrs until hour 24. Serum calcium, phosphate, and magnesium concentrations were measured every 6 hrs from hours 0 to 24. Serum amylase, lipase, and triglyceride concentrations were measured at hour 0 and then 12, 24, and 48 hrs after the initiation of therapy. We performed multivariable analyses to test for associations between clinical variables and pancreatic enzyme elevation in 67 children with DKA. Lipase was elevated in 21 (31%) and amylase in 16 (24%) of the children. Pancreatic enzyme values peaked 12-24 hrs after admission. There was no significant correlation between pancreatic enzyme elevation and abdominal pain. In multivariable analyses, an elevated blood urea nitrogen (BUN) concentration was associated with elevated serum amylase (odds ratio 1.04 per unit increase; 95% confidence interval, 1.01-1.09; p = .02), and elevated BUN concentrations and hypophosphatemia were associated with elevated serum lipase (odds ratio 1.04 per unit increase; 95% confidence interval, 1.00-1.08; p = .04; and odds ratio 0.35 per unit increase; 95% confidence interval, 0.15-0.81; p = .01, respectively). Elevation of pancreatic enzymes is common in children with DKA, but clinical pancreatitis is rare. Pancreatic enzyme levels reach a peak 12-24 hrs after initiation of treatment for DKA. Pancreatic enzyme elevation is associated with increased BUN concentrations at presentation but is not associated with abdominal pain.

Cases from the Osler Medical Service at Johns Hopkins University

PRESENTING FEATURES: A 36-year-old African American woman was admitted with a history of chills, fever, productive cough, and malaise of several days' duration, as well as an increase in baseline dyspnea on exertion. Her past medical history was notable for hemodialysis-dependent end-stage renal disease due to hypertension. Two years before admission, she successfully underwent angioplasty for a right subclavian vein stenosis due to a dialysis catheter. Nine months before admission, she had a new arteriovenous fistula placed in her right forearm because the fistula in her left arm had repeated complications, including pseudoaneurysm formation and thrombosis. Since placement of the new fistula, she noticed a steady, gradual increase in the size of her right breast and right upper arm. She also slowly developed worsening dyspnea on exertion, as well as back pain associated with her enlarged breast. A mammogram performed 3 months before admission revealed substantial vascular and lymphatic engorgement in the right breast but no distinct mass. The left breast had similar, although less dramatic, changes, as well as a 2.0- × 1.5-cm mass in the left lower quadrant. On physical examination, the patient was febrile (103.9 oF), with a heart rate of 123 beats per minute, blood pressure of 192/114 mm Hg, and oxygen saturation of 99% on room air. She was a moderately obese woman in mild distress. Her left breast was dysplastic. Her right breast was massively enlarged (Figure 1), about eight times the size of her left breast, with peau d'orange skin changes (Figure 2). There were no palpable masses in either breast. Numerous large subcutaneous veins were visible over her right breast, right arm, upper abdomen, and posterior chest. She had posterior cervical subcentimeter lymphadenopathy with no palpable axillary lymph nodes. Breath sounds were markedly diminished in the lower half of her right lung field with dullness to percussion in this area. Heart sounds were normal with an elevated jugular venous pressure to the level of the jaw. Her abdomen was benign. Extremities were normal except for an edematous, enlarged right arm. Neurologic examination was normal. Laboratory studies were normal except for an elevated blood urea nitrogen concentration and creatinine levels that were consistent with chronic renal failure. A chest radiograph showed a moderate right pleural effusion and small left pleural effusion. Chest computed tomographic (CT) scan with contrast confirmed these findings and also revealed dependent atelectasis overlying both pleural effusions, asymmetrical thickening, enlargement of soft tissue in the right breast, multifocal nodular opacities in bilateral lung fields, and dilation of the internal mammary vein, azygous venous system, and chest wall veins. A right thoracentesis revealed transudative fluid with negative cultures and normal cytopathology. What is the diagnosis?

Prevalence of Nephropathy in Black Patients with Type 2 Diabetes mellitus

The prevalence of nephropathy in black patients with type 2 diabetes mellitus is poorly defined. We performed a cross-sectional analysis of 98 unrelated and unselected black type 2 diabetic patients treated in indigent care internal medicine clinics to determine the prevalence of proteinuria and nephropathy. Serum creatinine, blood urea nitrogen, urine albumin and urine creatinine concentrations were measured. A Spearman’s rank correlation was computed to test for a relationship between diabetes duration and continuous outcomes. For binary outcomes, an odds ratio and 95% confidence interval were computed for a change of 10 years diabetes duration based on logistic regression. Cases were 61% female, and had mean (± SD) age 59.9 ± 12.5 years, diabetes duration 12.6 ± 9.4 years, body mass index 32.4 ± 9.3 kg/m², hemoglobin A1C (HbA1C) 9.2 ± 2.3%, and serum creatinine concentration 1.60 ± 1.1 mg/dl. For continuous variables, diabetes duration was positively associated with albuminuria (r = 0.31; p = 0.0017), serum creatinine (r = 0.36; p = 0.0003) and blood urea nitrogen concentration (r = 0.36; p = 0.0003). For binary variables, cases with longer diabetes duration were at increased risk for urinary albumin:creatinine >300 µg/mg (p = 0.006), elevated serum creatinine concentration (≧1.4 mg/dl in women or ≧1.6 mg/dl in men; p = 0.045), elevated blood urea nitrogen concentration (≧20 mg/dl; p = 0.026), and clinical cerebrovascular disease (p = 0.028). HbA1C, body mass index, and blood pressure did not correlate with diabetes duration in this population. Among the cases, 33.7% had elevated serum creatinine concentration and 71.5% had abnormal levels of albuminuria (27.6% > 300 µg albumin/mg Cr and 43.9% 30–300 µg albumin/mg Cr). Abnormal proteinuria was seen in the majority of black patients with poorly controlled type 2 diabetes mellitus treated in indigent care clinics. This prevalence may be conservative, due to the widespread use of angiotensin-converting enzyme inhibitor therapy and exclusion of cases treated only by nephrologists. Approximately 70% of black patients with type 2 diabetes cared for in indigent care clinics have abnormal proteinuria and are at heightened risk for ESRD and death.

Energy, Protein, and Seasonal Influences on White-Tailed Deer Fawn Nutritional Indices

Shortand long-term influences of dietary energy and protein on physiological indices of nutritional status were determined in a factorial experiment with 12 male and 12 female captive whitetailed deer (Odocoileus virginianus) fawns. Blood and urine samples were collected after 1, 2, 4, 8, 16, and 32 weeks on experimental diets. Body weights throughout the experiment were greater (P < 0.001) for male than for female fawns. Concentrations of blood urea nitrogen (BUN) and urinary urea/creatinine (U/C) ratios throughout the experiment were greater (P < 0.001) in fawns on high protein diets than in fawns on low protein diets. Blood urea nitrogen concentrations and urinary U/C ratios also were greater (P < 0.01) in fawns on low energy diets than in fawns on high energy diets over the duration of the experiment. A substantial reduction in BUN concentrations was observed after 8 months in those fawns which initially exhibited elevated BUN concentrations. Significant differences were observed among sample periods during the 8-month experiment for hemoglobin, packed cell volume, mean corpuscular hemoglobin content, albumin, BUN, cholesterol, nonesterified fatty acids, total ketone bodies, and urinary U/C ratios. J. WILDL. MANAGE. 46(2):302-312 Physiological indices for assessing nutritional status of populations of wild animals, most notably cervids, have long been the subject of research in wildlife science. Biochemical analyses of blood and urine hold promise as being reliable nutritional indices. However, assessing nutritional status with these methods must necessarily depend on controlled experiments to evaluate their efficiency and accuracy. Several investigators have examined nutritional indices of whitetailed deer under controlled conditions (Kirkpatrick et al. 1975, Seal et al. 1978a, Bahnak et al. 1979). No reports have been found in which differences in nutritional indices according to energy, protein, sex, and duration of dietary exposure were examined in a single experiment. The objective of the present study was to determine the shortand long-term effects of dietary energy and protein on nutritional indices of male and female white-

Effects of dietary polychlorinated biphenyls and polybrominated biphenyls on the renal and hepatic toxicities of several chlorinated hydrocarbon solvents in mice

Male ICR mice were fed a control diet or the same diet supplemented with 100 ppm polybrominated biphenyl (PBB) or 200 ppm polychlorinated biphenyl (PCB) for 28 d before single ip injections of various quantities of trichloroethylene (TRI), tetrachloro‐ethylene (TET), 1,1,2‐trichloroethane (TCE), or carbon tetrachloride (CCI 4 ). The ratio of liver weight to body weight was increased by dietary PBB and dietary PCB. PBB appeared to be more potent in this respect. Functional damage to the liver (elevated serum glutamic oxaloacetic transaminase activity) was not produced by acute administration of TRI, TET, or TCE. CCI A ‐induced liver damage was greater in PCB‐treated mice than in controls, and greater in PBB‐treated than in PCB‐treated mice. Functional renal damage (elevated blood urea nitrogen concentration, decreased organic anion transport capacity) was produced by acute administration of all solvents except TET. TRI‐induced renal dysfunction was potentiated by dietary PBB and dietary PCB. Both TCE‐induc...