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PubMed2004

Nutritional impairment in juvenile idiopathic arthritis.

OBJECTIVE: To investigate the relationship between nutritional impairment, measured by body mass index (BMI), expressed as an age- and sex-standardized standard deviation score (BMI SDS), and disease and patient characteristics in a UK cohort of children with juvenile idiopathic arthritis (JIA). A subgroup with available dietary information were analysed separately. METHODS: Important disease and patient characteristics (age, gender, disease subtype, swollen joint count, painful joint count, restricted joint count, treatment and dietary assessment) were assessed as potential explanatory measures of BMI SDS in a multiple linear regression. RESULTS: Data were collected on 123 consecutive patients. Twenty were nutritionally impaired. In multiple regression analysis excluding the dietary data, disease subtype [persistent oligoarthritis and polyarthritis (rheumatoid factor-negative)], five or more joints with reduced range of movement and being younger were associated with lower BMI SDS (P<0.001). When energy and protein intake were included in the analysis for a subgroup of children, the resulting model retained only disease subtype as a predictor of a low BMI SDS (P = 0.013). CONCLUSIONS: In this unselected population of children with JIA, 16% had evidence of undernutrition. The most commonly affected subtype was oligoarthritis, a previously unreported finding. There is no evidence from this study that this nutritional impairment results from inadequate food intake and it is likely that it is multifactorial in aetiology, disease subtype being the most important factor.

Adolescent↗

PubMed2001

Evolution of depressive symptoms in human immunodeficiency virus-infected patients entering primary care.

Our purpose was to examine among HIV-infected patients a) characteristics associated with depressive symptoms at initial primary care presentation and b) factors associated with improvement in depressive symptoms. We interviewed HIV-infected patients at initial presentation and reassessed them 6 months later. At baseline and follow-up, we collected data on depressive symptoms (CES-D) and other characteristics. Using multiple linear regression, we examined associations between CES-D score and baseline variables. We used multiple logistic regression to examine factors associated with improvement in depressive symptoms. Seventy-one percent of the baseline sample (N = 203) scored above the threshold considered indicative of depression. At 6 months, 36% of the subjects who were followed improved in depressive symptoms. Higher baseline CES-D scores, improvements in HIV-related symptoms, and joining a support group were associated with improvement. Depressive symptoms in this urban HIV-infected population were highly prevalent. It is essential to screen, identify, and treat depression among patients entering care for HIV disease. Encouragement in joining support groups is a reasonable component of a strategy for addressing this common condition.

Adult↗

PubMed1997

Metabolic determinants of the age-related improvement in one-mile run/walk performance in youth.

We examined the metabolic determinants of the age-related improvement in 1-mile run/walk (MRW) performance in boys and girls. Treadmill VO2peak (ml.kg-1.min-1), running economy (VO2 in ml.kg-1.min-1 at 8 km.h-1; VO2econ), and %VO2peak used during a simulated MRW were determined in 92 boys and 53 girls, 7-17 yr of age. Simple linear regression analyses indicated that MRW time decreased 0.52 min.y-1, VO2econ decreased 1.0 ml.kg-1.min-1.y-1, %VO2peak increased 1.5%.y-1, and no significant change occurred in VO2peak. Multiple linear regression analyses indicated that the increase in %VO2peak used during the run accounted for about 42% of the decrease in MRW time with age. With the effects of VO2peak and %VO2peak held constant, the improvement in VO2econ accounted for an additional 31% of the age-related decrease in MRW time. We conclude that the age-related improvement in MRW performance in youth is explained primarily by an increase in the %VO2peak used during the MRW and improvement in VO2econ. Age-related changes in MRW time should not be used to infer changes in VO2peak.

Adolescent↗

PubMed2001

Association between vitamin E and enhanced athletic performance in sled dogs.

PURPOSE: To determine the association between prerace plasma vitamin E concentration and performance in sled dogs competing in the 1998 Iditarod Race. METHODS: Prerace blood samples were collected from 670 dogs. Samples were analyzed for plasma vitamin E concentration while controlling for selected hematological and biochemical variables and signalment. Starting in teams of 16, exercise consisted of running up to 1159 miles pulling a laden sled and musher via checkpoints. The records of dogs that were withdrawn from the race for health reasons, fatigue, or strategic or technical reasons, and those of dogs that finished the race were analyzed. Multiple logistic regression and Cox proportional hazards analysis were used to determine factors associated with endurance. Multiple linear regression analysis was used to determine factors associated with team speed. RESULTS: A total of 323 dogs (48%) were withdrawn from racing at various distances from the start. Median time to finish for 39 teams was 11.5 d and the winning time was 9.2 d. Dogs with prerace plasma vitamin E concentrations > 40.7 microg.mL-1 were 1.9 times more likely to finish (P = 0.0006) and had 1.8 times less of a risk of being withdrawn for every mile ran (P = 0.03) than were dogs with plasma vitamin E concentrations between 16.3 and 40.7 microg.mL-1. Neither a team's mean prerace vitamin E concentration, nor the proportion of dogs within a team with high (> 40.7 microg.mL-1) vitamin E concentration was associated with team speed. CONCLUSIONS: Dogs with higher plasma vitamin E concentrations have enhanced endurance compared with dogs with lower plasma vitamin E concentrations, but the plasma vitamin E status of a team is not associated with team speed.

Animals↗

PubMed1994

Progression of renal failure in chronic primary glomerular diseases.

The rate of progression of renal failure was analyzed in 19 patients with biopsy-proven chronic primary glomerular diseases, by the slope (regression coefficient) of the linear regression of reciprocal serum creatinine on time. The relative importance of proteinuria, sex, underlying disease and components of arterial pressure (systolic, diastolic and mean) was tested using stepwise multiple linear regression, the dependent variable being the slope of progression. We found that the only variable significantly related with slopes of progression was arterial pressure. Hypertension was found in 14 of the 19 patients. There was a significant linear relationship (p < 0.05) between mean arterial pressure and slopes of progression. Notwithstanding, the best fit to the data follows a quadratic function (p < 0.001 for mean arterial pressure), which corresponds to a negative parabolic curve. Therefore, either low or high values of mean arterial pressure were associated with faster mean progression rates. Thus, an accurate approach of this relationship fits a nonlinear regression model.

Adolescent↗

PubMed2003

[Age determination by radiographic feature of thyroid cartilage in male Chinese Han popullation].

OBJECTIVE: To seek a exact method of age determination. METHODS: This sample consists of 73 male Chinese han individuals whose ages have been known. Eight positions were selected from their radiograms which have been divided into three or six grade and then set up a mathematical model to deduce age by multiple linear regression analysis. RESULTS: The standard deviation of male thyroid cartilage is 1.854 and the multiple correctation coefficient is 0.9971. CONCLUSION: The observation proved that age determination by radiographic feature of thyroid cartiage may be suitable for male Chinese han population from 13 to 67 years old.

Adolescent↗

PubMed1993

Maternal ethnicity and birthweight among blacks.

This paper examines the association of ethnicity and birthweight, adjusted for other maternal and infant characteristics, among black women who gave birth in Massachusetts from 1987 through 1989. Data are drawn from the standard certificate of live birth, which includes questions on race and ethnicity/ancestry as well as birthweight; maternal sociodemographic and biological characteristics; access to prenatal care; and infant characteristics. The study cohort consists of 18,571 black infants and a comparison group of 206,358 non-Hispanic white infants. Infants whose mothers reported their race as black were further categorized into six ethnic groups: American, Haitian, West Indian, Cape Verdean, Hispanic, and other black. In addition to descriptive analyses, we used multiple linear regression to measure the association between ethnicity, other characteristics, and birthweight; and we used multiple logistic regression to measure the odds ratio of low birthweight (ranging from 500 g to 2499 g) for the six black ethnic groups, adjusted for other characteristics. Results indicate that Americans have lower mean birthweight and generally higher levels of risk than other black ethnic groups. Compared to the reference group of non-Hispanic whites, Americans (OR = 1.49), other blacks (OR = 1.41), and West Indians (OR = 1.37) have significantly elevated relative risks of low birthweight.

Adult↗

PubMed1996

Sequential evaluation of portal venous hemodynamics by Doppler ultrasound in patients with severe acute hepatitis.

OBJECTIVES: Portal hypertension may develop in patients with severe acute hepatitis. Sequential changes of portal venous hemodynamics in acute hepatitis is not well understood. This study evaluated portal hemodynamic changes and prognostic values in patients with severe, acute hepatitis. METHODS: Doppler studies, liver function tests, and virology studies were done in the inclusion, the 3rd month, and the 6th month for patients with severe, acute hepatitis. An indocyanine green clearance was done in the inclusion. Doppler portal hemodynamic studies were done in the hilar area by an average of two measurements. RESULTS: A total of 88 consecutive patients was included. Nine of them died. On initial study, fatalities were generally older patients with more delayed indocyanine green clearance, lower portal vein velocity, lower albumin values, higher bilirubin values, longer prothrombin time, and ascites. Using stepwise logistic regression, portal blood flow and prothrombin time were the two independence prognostic factors. By multiple linear regression, portal blood flow was associated with ascites, and average portal blood velocity was associated with bilirubin. During the hospital days, transient, depressed portal blood velocities followed by a hyperdynamic stage were found in survivors. The portal vein velocity changes for fatalities either were kept at a lower level or had a declining pattern. CONCLUSIONS: Doppler ultrasound detects portal hemodynamic changes for patients with severe, acute hepatitis. Sequential portal hemodynamic studies will be helpful for evaluating patients with severe, acute hepatitis.

Acute Disease↗

PubMed2006

Quantitative structure-activity (affinity) relationship (QSAR) study on protonation and cationization of alpha-amino acids.

A quantitative structure-activity (affinity) relationship (QSAR) study is carried out to model the proton, sodium, copper, and silver cation affinities of alpha-amino acids (AA). Stepping multiple linear regression (MLR), partial least squares (PLS), and artificial neural network (ANN) approaches are applied to elucidate the multiple factors affecting these affinities. The MLR and PLS models reveal that the variation in proton affinity is attributed to the highest electrophilic superdelocalizability of nitrogen (major) and the number of rotatable bonds (minor) in AA. The noncovalent interactions, especially ion-dipole interactions, are responsible for the changes in Na+ affinity. The ionization potential, dipole moment of the side chain, and degree of linearity are the properties of AA that give the best correlation with the Cu+ and Ag+ affinities. The ANN models are developed to study the relationships (linear or nonlinear) between the molecular descriptors and binding affinities. The ANN models show higher predictive power. The QSAR models are used to study the binding forms of AA (neutral vs zwitterionic) upon protonation/cationization. To our knowledge, this is the first attempt to carry out a QSAR study on protonated/cationized AlphaAlpha to elucidate their binding properties. In virtue of the Na+ affinity ANN model, the Na+ affinities of dihydroxyphenylalanine (DOPA) were predicted. This work may pave the way for the success of applying similar approaches to peptides or proteins (with AA as the building blocks) in the future.

Amino Acids↗

PubMed2001

[Volumetric pumps for blood transfusions. Viability in pediatrics].

UNLABELLED: The authors determine whether or not nurses should use perfusion pumps for concentrated hematin transfusions, measuring the degree of hemolysis which occurs in two distinct models. METHODOLOGY STUDY SAMPLE: Concentrated hematin transfusions by means of an infusion pump on children in a Pediatrics Intensive Care Unit at the Maternity-Pediatrics Ward in Granada. Dependent Variable: Degree of Hemolysis, measured by means of: free hemoglobin, potassium, LDH. INDEPENDENT VARIABLES: Pump; dated/used blood; hematocrit; catheter caliber; type of procedure; pump working pressure; other perfusion rhythms; infusion rhythm. Sample size. One year study group, 95% confidence rate, 0.50 prevalence of awaited hemolysis, +/- 0.05 precision (relative precision 10%). Data Obtained: Two samples are taken per transfusion: removal of blood bag, extreme distal removal system. Investigative Method: Prospective descriptive study. STATISTICAL ANALYSIS: Descriptive statistics, by means of frequency distributions. Variable analysis, multiple variable analysis. RESULTS: 55 observations were carried, of these, 50.9% corresponded to pump number one. Simple regression linear analysis showed differences in the degree of hemolysis in terms of free hemoglobin and hematocrit. Dated/used blood registered a higher hemolysis level above 75 percentile. The greater hemolysis in terms of potassium difference was associated with the type of procedure, having an average of 0.44 mEq/l, in presence of other perfusions, greater rhythm (p = 0.118), dated/used blood (p = 0.008), hematocrit (p = 0.063). The greatest difference in LDH occurred with smaller caliber catheters, other perfusions, more dated blood (p = 0.117). In multiple linear regression, results were equal to those predicted: an average difference in hemoglobin of 3.87 mg/l (p = 0.661); in potassium, 0.39 mEq/l (p = 0.138); in LDH, 53.6 (p = 0.568). This documents with verify this study have been consulted by the ROL Editorial Board and may be requested from the authors.

Blood Transfusion↗

PubMed1983

Interrelationships among human chorionic gonadotropin (hCG), 17 beta-estradiol, progesterone, and estriol in maternal serum: evidence for an inhibitory effect of the fetal adrenal on secretion of hCG.

In normal pregnancy, maternal serum hCG reaches a maximum concentration about 8-10 weeks after the last menstrual period and then decreases. To investigate the possibility that this decrease in hCG is produced by an inhibitory effect of steroids originating in the feto-placental unit, hCG, progesterone, 17 beta-estradiol, and estriol were determined by specific RIAs in 341 serum specimens obtained from 229 different pregnancies. Expressions for predicted hCG as a function of estimated trophoblastic mass and percent predicted hCG were determined to correct for the increase in hCG with increasing trophoblastic mass. The relationships between hCG and progesterone, 17 beta-estradiol, estriol, or estimated trophoblastic mass were not linear. Expression of the hCG data as percent predicted hCG produced linear relationships between hCG and each of the above steroids. Both hCG itself and percent predicted hCG were shown to have a negative regression on estriol (P less than 0.001) and a positive regression on progesterone (P less than 0.001), but not on 17 beta-estradiol (P greater than 0.05), in a multiple linear regression on all three steroids. These data suggest that hCG production is inhibited by a steroid originating in the fetal adrenal. This inhibitory effect plateaus in late pregnancy, allowing a minor late increase in hCG due to increasing trophoblastic mass.

Adrenal Glands↗

PubMed2004

Comparative analysis of passive dosimetry and biomonitoring for assessing chlorpyrifos exposure in pesticide workers.

Under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), the US Environmental Protection Agency (EPA) has the authority to regulate the use of pesticides to prevent unreasonable adverse human health effects associated with pesticide exposure. Accordingly, the EPA requires pesticide registrants to perform studies evaluating the potential for pesticide handler exposure. Data from five such studies that included exposure measurements based on both external measurements and biological monitoring were used to examine methods of assessment, routes and determinants of exposure and dose to the pesticide chlorpyrifos. Eighty workers across four job classes were included: mixer/loaders (M/L, n = 24), mixer/loader/applicators (M/L/A, n = 37), applicators (A, n = 9) and re-entry scouts (RS, n = 10). Results showed that doses were highly variable and differed by job class (P < 0.05) with median total (inhalation and dermal combined) exposure-derived absorbed doses (EDADtot) of 129, 88, 85 and 45 microg/application for A, M/L/A, M/L and RS, respectively. Doses derived from the measurement of 3,5,6-trichloro- 2-pyridinol (3,5,6-TCP) in urine were similar in magnitude but differed in rank with median values of 275, 189, 122 and 97 microg/application for A, M/L, RS, and M/L/A, respectively. The relative contribution of dermal to inhalation exposure was examined by their ratio. The median ratios of exposure-derived absorbed dermal dose (EDADderm) (assuming 3% absorption) to exposure-derived absorbed inhalation dose (EDADinh) (assuming 100% absorption) across job classes were 1.7, 1.5, 0.44 and 0.18 for RS, M/L, A and M/L/A, respectively, with an overall median of 0.6. For 34 of 77 workers (44%), this ratio exceeded 1.0, indicating the significance of the dermal exposure pathway. Different dermal absorption factor (DAF) assumptions were examined by comparing EDADtot to the biomarker-derived absorbed dose (BDAD) as a ratio where EDADtot was calculated assuming a DAF of 1, 3 and 10%. Median ratios of 0.45, 0.71 and 1.28, respectively, were determined suggesting the DAF is within the range of 3-10%. A simple linear regression of urinary 3,5,6-TCP against EDADtot indicates a positive association explaining 29% of the variability in the 3,5,6-TCP derived estimate of dose. A multiple linear regression model including the variables EDADderm, EDADinh and application type explained 46% of the variability (R2 = 0.46) in the urinary dose estimate. EDADderm was marginally significant (P = 0.066) while EDADinh was not (P = 0.57). The EDADderm regression coefficient (0.0007) exceeded the coefficient for EDADinh (0.00002) by a factor of 35. This study demonstrates the value of the pesticide registrant database for the purpose of evaluating pesticide worker exposure. It highlights the significance of the dermal exposure pathway, and identifies the need for methods and research to close the gap between external and internal exposure measures.

Agriculture↗

PubMed1993

An epidemiologic study of osteoporosis in Taiwan.

In 1989, a cross-sectional study was carried out in Taiwan to understand the distribution of bone mineral density (BMD) in the lumbar spine of Chinese people and to identify the risk factors associated with osteoporosis. BMD of the lumbar spine was measured by dual-photon absorptiometry in 404 healthy volunteers (266 women and 138 men, aged 15 to 83 years) living in Lin-Kou Township. The age-specific mean values of lumbar spine BMD were higher for men than for women after age 60. Furthermore, the BMD of women declined significantly after age 40. However, the BMD of men did not show a downward trend with age. In a multiple logistic regression analysis of fracture risk expressed as a categorical level of BMD, age, diabetes, and years since menopause were associated with lower BMD, while body mass index was associated with higher BMD. In a multiple linear regression analysis of BMD, significant variables were years since menopause, age, body mass index, and seaweed diet. Variables that were significant in bivariate analysis, but not multiple variable analysis were education, milk consumption, breast-feeding, frequency of pregnancy, and age at first menstruation. However, cigarette habits, alcohol consumption, and physical activity were not associated with the BMD level in any of these analyses.

Absorptiometry, Photon↗

PubMed2005

Assessing cardiorespiratory fitness without performing exercise testing.

BACKGROUND: Low cardiorespiratory fitness (CRF) is associated with increased risk of chronic diseases and mortality; however, CRF assessment is usually not performed in many healthcare settings. The purpose of this study is to extend previous work on a non-exercise test model to predict CRF from health indicators that are easily obtained. METHODS: Participants were men and women aged 20 to 70 years whose CRF level was quantified with a maximal or submaximal exercise test as part of the National Aeronautics and Space Administration/Johnson Space Center (NASA, n = 1863), Aerobics Center Longitudinal Study (ACLS, n = 46,190), or Allied Dunbar National Fitness Survey (ADNFS, n = 1706). Other variables included gender, age, body mass index, resting heart rate, and self-reported physical activity levels. RESULTS: All variables used in the multiple linear regression models were independently related to the CRF in each of the study cohorts. The multiple correlation coefficients obtained within NASA, ACLS, and ADNFS participants, respectively, were 0.81, 0.77, and 0.76. The standard error of estimate (SEE) was 1.45, 1.50, and 1.97 metabolic equivalents (METs) (1 MET = 3.5 ml O(2) uptake.kilograms of body mass(-1).minutes(-1)), respectively, for the NASA, ACLS, and ADNFS regression models. All regression models demonstrated a high level of cross-validity (0.72 < R < 0.80). The highest cross-validation coefficients were seen when the NASA regression model was applied to the ACLS and ADNFS cohorts (R = 0.76 and R = 0.75, respectively). CONCLUSIONS: This study suggests that CRF may be accurately estimated in adults from a non-exercise test model including gender, age, body mass index, resting heart rate, and self-reported physical activity.

Adult↗

PubMed1993

Hyperopia and neovascularization in age-related macular degeneration.

PURPOSE: Refractive errors for phakic eyes of patients referred with age-related macular degeneration were reviewed to determine whether some range of refractive error might be a risk factor for the neovascular form. METHODS: The authors compared refractive errors of 198 patients with unilateral neovascular disease with refractive errors of 129 patients with bilateral dry disease. These groups had comparable distributions with respect to age, sex, and visual acuity of their better eyes. Student's t tests and multiple linear regression analyses were performed to assess group differences in mean refractive error. Contingency table and multiple logistic regression analyses were performed to determine odds ratios for having the neovascular form based on a stratification of refractive error. RESULTS: By comparing better eyes of the two groups, patients with the unilateral neovascular form had an average spherical equivalent that was 1.0 diopter (D) more hyperopic than that of patients with the bilateral dry form (P < 0.001). Patients with a refractive error of +0.75 D or greater were more likely to have the neovascular form compared with patients with other refractive errors (odds ratio, 2.40; 95% confidence interval, 1.53-3.78; P < 0.001). Similar relationships between the two groups of patients were found by comparing worse eyes. CONCLUSION: These findings suggest that hyperopia is a risk factor for choroidal neovascularization among patients referred with age-related macular degeneration.

Aged↗

PubMed2000

Phenological weighting of ozone exposures in the calculation of critical levels for wheat, bean and plantain.

This paper presents phenological weighting factors to be applied to AOT40 (accumulated ozone exposure above a threshold of 40 nl l(-1)) ozone exposure-response relationships for crops at different growth stages. The quantification of such factors represents a step-forward in the derivation of Level II critical levels for ozone. The weighting factors presented are derived from published literature on the sensitivity of wheat (Triticum aestivum), bean (Phaseolus vulgaris) and plantain (Plantago major) to ozone at different growth stages. Weighting functions were calculated using either multiple linear regression or the reciprocal residual mean square (RMS(-1)). The resulting weights were transformed into multiplication factors to be applied to the monthly AOT40 during the 3-month assessment period of critical level exceedance. Interspecific differences were too large to allow for the development of a unified weighting function for the three species considered. For wheat grain yield, the derived multiplication factors varied by almost four-fold (0.40, 1.06, 1.54), while those for bean pod yield varied by only about 25% (0.85, 1.01, 1.14). The available data for plantain were restricted to short-term studies conducted under controlled conditions. These data were not suitable for the derivation of weighting factors comparable to those derived for bean and wheat. Based on known differences in wheat development and phenology across Europe, the need for a geographic differentiation of the time period for the calculation of the critical level exceedances is also discussed and examples provided of the adoption of the derived weightings in the mapping of critical level exceedances. Differences between critical level exceedance maps using weighted and unweighted AOT40 calculations are discussed.

Journal Article↗

PubMed2003

Determination of total sulfur in diesel fuel employing NIR spectroscopy and multivariate calibration.

A method for sulfur determination in diesel fuel employing near infrared spectroscopy, variable selection and multivariate calibration is described. The performances of principal component regression (PCR) and partial least square (PLS) chemometric methods were compared with those shown by multiple linear regression (MLR), performed after variable selection based on the genetic algorithm (GA) or the successive projection algorithm (SPA). Ninety seven diesel samples were divided into three sets (41 for calibration, 30 for internal validation and 26 for external validation), each of them covering the full range of sulfur concentrations (from 0.07 to 0.33% w/w). Transflectance measurements were performed from 850 to 1800 nm. Although principal component analysis identified the presence of three groups, PLS, PCR and MLR provided models whose predicting capabilities were independent of the diesel type. Calibration with PLS and PCR employing all the 454 wavelengths provided root mean square errors of prediction (RMSEP) of 0.036% and 0.043% for the validation set, respectively. The use of GA and SPA for variable selection provided calibration models based on 19 and 9 wavelengths, with a RMSEP of 0.031% (PLS-GA), 0.022% (MLR-SPA) and 0.034% (MLR-GA). As the ASTM 4294 method allows a reproducibility of 0.05%, it can be concluded that a method based on NIR spectroscopy and multivariate calibration can be employed for the determination of sulfur in diesel fuels. Furthermore, the selection of variables can provide more robust calibration models and SPA provided more parsimonious models than GA.

Journal Article↗

PubMed2001

Neutrophil activation and hyperamylasaemia after endoscopic retrograde cholangiopancreatography: potential role for the leukocyte in the pathogenesis of acute pancreatitis.

BACKGROUND AND STUDY AIMS: Hyperamylasaemia occurs in up to 60% of patients following endoscopic retrograde cholangiopancreatography (ERCP), and in a small proportion of patients (1-5%) acute pancreatitis may develop. We evaluated the role of the neutrophil in post-ERCP hyperamylasaemia and acute pancreatitis by measuring circulating CD11b adhesion receptor expression--an indicator of leukocyte activation. PATIENTS AND METHODS: A total of 43 patients undergoing elective ERCP were studied. Peripheral blood measurements of amylase activity and neutrophil CD11b content (by flow cytometry) were made immediately before ERCP (baseline), and at 2 and 24 hours after the procedure. RESULTS: ERCP induced an increase in amylase level above baseline in 41 of 43 patients. The 2-hour and 24-hour post-ERCP amylase levels were directly related (R = 0.9, P < 0.01). Baseline CD11b receptor status was positively correlated with post-ERCP amylase activity (R = 0.4, P < 0.05), and this relationship was stronger when pancreatography had been performed (R = 0.67, P < 0.01). Three patients (7%) developed clinical acute pancreatitis, with post-ERCP amylase levels persistently elevated above 1000 IU/l. Multiple linear regression identified CD11b expression as the most significant explanatory variable for amylase level after ERCP (multiple R = 0.74, P < 0.01). CONCLUSIONS: The findings from this pilot study indicate an association between neutrophil activation and hyperamylasaemia following ERCP, and suggest a role for this leukocyte in the pathogenesis of pancreatitis. Further study of neutrophil characteristics may allow identification of individual susceptibility to ERCP-induced pancreatic injury.

Acute Disease↗