Amniotic fluid gamma-glutamyl transferase for prediction of biliary atresia in cases of non-visualisation of the fetal gallbladder: a retrospective study using a validated analytical platform and local reference range.

INTRODUCTION: The level of amniotic fluid gamma-glutamyl transferase (AFGGT) may help identify biliary atresia (BA) in cases of non-visualisation of the fetal gallbladder (NVFGB). This study aimed to validate a serum/plasma matrix-based gamma-glutamyl transferase (GGT) assay for amniotic fluid (AF) samples, establish a local gestational age-specific AFGGT reference range, and evaluate the efficacy of AFGGT for predicting fetal BA in pregnancies with NVFGB using the constructed reference range. METHODS: The analytical performance of a serum/plasma matrix-based GGT assay on AF samples was evaluated using a Cobas c502 analyser. Amniotic fluid gamma-glutamyl transferase levels in confirmed euploid singleton pregnancies (16+0 to 22+6 weeks of gestation) were determined using the same analyser to establish a local gestational age-specific reference range (the 2.5th to 97.5th percentiles). This local reference range was used to determine the positive predictive value (PPV) and negative predictive value (NPV) of AFGGT level <2.5th percentile for identifying fetal BA in euploid pregnancies with NVFGB. RESULTS: The serum/plasma matrix-based GGT assay was able to reliably and accurately determine GGT levels in AF samples. Using the constructed local gestational age-specific AFGGT reference range, the NPV and PPV of AFGGT level <2.5th percentile for predicting fetal BA in pregnancies with NVFGB were 100% and 25% (95% confidence interval=0, 53), respectively. CONCLUSION: In pregnancies with NVFGB, AFGGT level ≥2.5th percentile likely excludes fetal BA. Although AFGGT level <2.5th percentile is not diagnostic of fetal BA, fetuses with AFGGT below this level should be referred for early postnatal investigation.

High risk of conversion to diabetes in first-degree relatives of individuals with young-onset type 2 diabetes: a 12-year follow-up analysis.

AIM: Family history of diabetes is an established risk factor for Type 2 diabetes, but the impact of a family history of young-onset diabetes (onset < 40 years) on future risk of diabetes among first-degree relatives is unclear. In this prospective study, we examined the influence of family history of late- versus young-onset diabetes on the development of diabetes in a young to middle-aged Chinese population. METHODS: Some 365 siblings identified through probands with Type 2 diabetes and 452 participants from a community-based health awareness project (aged 18-55 years) who underwent metabolic assessment during the period 1998-2002 were followed to 2012-2013 to determine their glycaemic status. Multivariate logistic regression was performed to investigate the association of family history of diabetes presented at different age categories with development of diabetes. RESULTS: In this cohort, 53.4% (n = 167) of participants with a family history of young-onset diabetes, 30.1% (n = 68) of those with a family history of late-onset diabetes and 14.4% (n = 40) of those without a family history developed diabetes. Using logistic regression, family history of diabetes presented at ages ≥ 50, 40-49, 30-39 and < 30 years, increased conversion to diabetes with respective odds ratios of 2.4, 5.8, 9.4 and 7.0 (P < 0.001 for all), after adjustment for socio-economic status, smoking, obesity, hypertension and dyslipidaemia. Among participants without diabetes at baseline, risk association of family history of late-onset diabetes with incident diabetes was not sustained, whereas that of family history of young-onset diabetes remained robust on further adjustment for baseline glycaemic measurements. CONCLUSIONS: First-degree relatives of people with Type 2 diabetes, especially relatives of those with young-onset diabetes, are at high risk for diabetes.

Early gene-diet interaction between glucokinase regulatory protein (GCKR) polymorphism, vegetable and fish intakes in modulating triglyceride levels in healthy adolescents.

BACKGROUND AND AIMS: The benefits of dietary vegetable and fish consumptions on improving glucose and lipid metabolism have been well established. Recently, the T-allele of a common genetic variant rs780094 at glucokinase regulatory protein (GCKR) was reported to be associated with elevated triglyceride (TG) levels but reduced fasting plasma glucose (FPG) and type 2 diabetes risk. However, the dietary modulation on genetic risk is not clearly understood. METHODS AND RESULTS: A cohort of 2095 Chinese adolescents (mean age 15.6 ± 2.0 years, 45.3% male) recruited from a population-based school survey for cardiovascular risk factor assessment, with dietary data including weekly vegetable and fish consumptions as well as clinical data were genotyped for the GCKR rs780094 polymorphism. In the linear regression analysis with adjustment for sex, age, body mass index, and socioeconomic status (school banding, paternal and maternal education levels), the frequency of vegetable intake per week was inversely associated with FPG (P = 0.044). Individuals with low fish intake generally had elevated TG levels but reduced TC, HDL-C and LDL-C (0.006 < P < 0.029). We also observed significant associations of the minor T-allele of GCKR rs780094 with decreased FPG (P = 0.013) and increased TG levels (P = 2.7 × 10(-8)). There were significant gene-diet interactions between rs780094 and vegetable consumption (P(interaction) = 0.009), and between rs780094 and fish consumption (P(interaction) = 0.031) in modulating TG levels. The T-allele of GCKR locus was associated with higher TG levels amongst individuals with ≥7 vegetable meals per week (P = 6.4 × 10(-9)), and among individuals with <7 fish meals per week (P = 0.020 and 7.0 × 10(-7) for 4-6 and ≤3 meals per week, respectively). High intake of vegetable exerted a reduction in TG levels only among CC genotype carriers (Ptrend = 0.020), while high intake of fish was associated with reduced TG levels only among TT genotype carriers (Ptrend = 0.026). CONCLUSIONS: In summary, our data indicated that the favorable associations of higher vegetable and fish intakes on TG levels are dependent on the genetic background of an individual. In particular, at-risk TT- genotype carriers of the GCKR variant may derive more benefits from a high fish intake, while the CC-genotype carriers may find further benefits from a high consumption of vegetable.

IFCC educational materials on selected analytical and clinical applications of high sensitivity cardiac troponin assays.

In 2011, the IFCC Task Force on Clinical Applications of Cardiac Bio-Markers (TF-CB) was formed, with the purpose of providing evidence based educational materials to assist all biomarker users, i.e. laboratorians, clinicians, researchers, in-vitro diagnostics and regulatory agencies, in better understanding important analytical and clinical aspects of established and novel cardiac biomarkers for use in clinical practice and research. The goal of the task force was to promulgate the same information conjointly through the in vitro diagnostic industry to the laboratory, emergency department and cardiologists. The initial undertaking of the TF-CB, which is comprised of laboratory medicine scientists, emergency medicine physicians and cardiologists, was to address two key issues pertaining to implementing high-sensitivity cardiac troponin (hs-cTn) assays in clinical practice: the 99th percentile upper reference limit (URL) and calculating serial change values in accord with the Universal Definition of AMI. The highlights of both concepts from IFCC statements are described.

Associations of uric acid and gamma-glutamyltransferase (GGT) with obesity and components of metabolic syndrome in children and adolescents.

BACKGROUND: The combined effect of uric acid, gamma-glutamyltransferase (GGT) and cardiovascular risk factors clustering in the youth remains under-explored. OBJECTIVE: The objective of this study was to examine the association between uric acid, GGT, obesity and the individual components of metabolic syndrome in children and adolescents. METHODS: We performed a cross-sectional observational study of 2067 children and adolescents (875 boys and 1192 girls) aged 6-20 years who were healthy volunteers and were recruited from primary and secondary schools in Hong Kong between 2007 and 2008. Subjects were divided into two strata (75th percentile as cut-off) for comparison between odds of cardiovascular risk factors. RESULTS: After adjustment by multivariable logistic regression, subjects in upper stratum, i.e., >75th percentile, of either serum uric acid or GGT levels were associated with obesity, low high-density lipoprotein cholesterol (HDL-C) level and high blood pressure (adjusted odds ratios [AOR] ranged from 1.63 to 5.82, all P < 0.005) compared with those in the lower stratum. There were combined effect for upper stratum of both uric acid and GGT in the association with obesity, low HDL-C and high blood pressure (AOR ranged from 2.60 to 10.69, all P < 0.05) after adjustment for age, sex and body mass index z-score (except for obesity status) as well as body height (for high blood pressure). CONCLUSION: Uric acid and GGT have combined effect in association with obesity and other cardiovascular risk factors in children and adolescents.

PP103. Arterial stiffness in women with previous GDM - A follow up of Chinese HAPO study cohort.

INTRODUCTION: It is well known that women with history of gestational diabetes (GDM) are at risk of future DM. Whether they are at a higher risk of hypertension and cardiovascular risk remained to be determined. OBJECTIVES: To determine whether Chinese women who have been diagnosed GDM according to the new IADPSG criteria have a higher risk of hypertension & arterial stiffness than women with normal glucose tolerance (NGT) during pregnancy. METHODS: Chinese women who had participated in the HAPO study between 2001 and 2006 in Hong Kong were followed up at a median of 6years postpartum. All underwent anthropometric & BP measurements. Central systolic and diastolic blood pressures (SBP & DBP), augmentation index (AI) and pulse wave velocity (PWV) were assessed by using SphygmoCor(®) PVx.A total of 608 women (494 NGT, 114 GDM) were followed up till early 2012. RESULTS: Although there was no significant difference in the rate of hypertension, the central SBP (106±12 vs 102±13mmHg, p=0.03), AI (22.1±8.3 vs 18.9±8.5%, p<0.001) and PWV (6.8±1.0 vs 6.6±0.8, p=0.03) were all higher in women with history of GDM. CONCLUSION: The findings suggest a higher risk of subclinical atherosclerosis amongst women with GDM despite the blood pressure may appear normal at the time of follow up.

Sonographic measurement of mesenteric fat predicts presence of fatty liver among subjects with polycystic ovary syndrome.

OBJECTIVE: Visceral fat is believed to be important in the pathogenesis of metabolic syndrome and fatty liver. In this study, we examined the relationship between mesenteric fat thickness and other sonographic indices of adiposity and the presence of fatty liver among subjects with polycystic ovary syndrome (PCOS). SUBJECTS AND METHODS: A total of 117 Chinese subjects with PCOS were evaluated (mean age, 28.6 ± 6.5 yr; mean body mass index, 24.3 ± 5.3 kg/m(2)). Anthropometric measurements and metabolic risk profile, including a standard oral glucose tolerance test, were assessed in all subjects. All subjects underwent an ultrasound examination for measurement of thickness of mesenteric, preperitoneal, and sc fat as well as evaluation for fatty liver. RESULTS: Forty-six (39.3%) of the subjects had fatty liver. PCOS subjects with fatty liver had higher body mass index, waist circumference, waist-hip ratio, and systolic blood pressure; a more unfavorable lipid profile with higher triglyceride; lower high-density lipoprotein cholesterol; higher fasting glucose and insulin; higher 2-h glucose during oral glucose tolerance test; lower SHBG; and higher alanine aminotransferase. Subjects with fatty liver had increased thickness of preperitoneal, mesenteric, and sc fat, as well as increased carotid intima-media thickness. Abdominal fat thickness showed moderate correlation to alanine aminotransferase as well as fasting insulin. On multivariate logistic regression, fasting insulin and mesenteric fat thickness were identified as independent predictors of fatty liver among subjects with PCOS. CONCLUSION: Fatty liver is present in a significant proportion of Chinese patients with PCOS. Sonographic measurement of mesenteric fat is an independent determinant of fatty liver among subjects with PCOS and identifies subjects at increased cardiovascular risk.

Life-threatening Torsades de Pointes resulting from "natural" cancer treatment.

INTRODUCTION: Nonradioactive cesium chloride (CsCl) is used by some alternative medicine advocates as a treatment for cancer. The therapy was proven to be neither safe nor effective. Chronic use of CsCl has resulted in cases with severe cardiotoxicity. CASE REPORT: A 65-year-old lady presented to our hospital's accident and emergency department with recurrent syncope attacks. Electrocardiogram monitoring showed QT prolongation and transient Torsades de Pointes (TDP) ventricular tachycardia. She was taking anticancer naturopathic drugs for 6 weeks before admission. One of her naturopathic drugs was subsequently confirmed containing 89% CsCl by weight. Besides conventional treatment of QT prolongation and TDP, the patient was given a 4-week course of oral Prussian blue to enhance gastrointestinal elimination of cesium. The serum half-life of cesium was reduced from 61.7 to 29.4 days after the use of Prussian blue. QT prolongation was normalized in 27 days. DISCUSSION: To our knowledge, this is the first published case of nonradioactive cesium poisoning treated with Prussian blue. A transient rise in serum cesium level was observed during Prussian blue therapy. Possible explanations for this observation include poor drug compliance during outpatient treatment and redistribution of cesium from body stores. CONCLUSION: Nonradioactive CsCl poisoning can result in severe cardiotoxicity with QT prolongation and TDP ventricular tachycardia. The key points in the management of nonradioactive cesium poisoning include cessation of cesium exposure, vigorous electrolytes replacement, and oral Prussian blue therapy.

Elevation of pro-inflammatory cytokines, C-reactive protein and cardiac troponin T in chronic renal failure patients on dialysis.

Chronic renal failure (CRF) patients suffer from a chronic inflammation. They are at increased risk of cardiovascular disease. In order to investigate this inflammatory process and cardiovascular risk factors associated with haemodialysis (HD) and peritoneal dialysis (PD), we compared serum/plasma pro-inflammatory cytokines, C-reactive protein (CRP), and cardiac troponin T (cTnT) of 146 CRF patients treated or not treated with PD or HD. Serum cytokines and CRP as well as plasma cTnT were measured by enzyme-linked immunosorbent assay, chemiluminescence immunoassay, and electrochemiluminescence immunoassay, respectively. Results indicated that serum interleukin (IL)-18 concentrations were significantly higher in PD and low creatinine clearance pre-dialysis CRF (LCC) patients than HD patients (both p < 0.05). IL-6 and tumour necrosis factor (TNF)-alpha concentrations were significantly higher in PD patients than LCC patients (both p < 0.01). Serum hsCRP and plasma cTnT in HD were significantly higher than LCC (both p < 0.01). The elevation of pro-inflammatory cytokines should play an important role in the chronic inflammation and increased cardiovascular risk of CRF patients on dialysis. We are evaluating further the diagnostic and prognostic applications of pro-inflammatory cytokines and biochemical inflammatory markers for these patients.

Near-miss errors in laboratory blood test requests by interns.

BACKGROUND: Human errors have proven to be one of the most formidable patient care challenges in acute hospital setting. AIM: To evaluate the at-risk period for near-miss errors in laboratory blood test requests, in an acute medical hospital. DESIGN: Hospital-based retrospective analysis. METHODS: We reviewed the database of voluntary reports for near-miss errors for laboratory blood test requests by 104 medical residents in their first postgraduate year (interns), over a 2-year period (October 2002 to September 2004). To identify patterns and causal factors we analysed the reports with respect to months of working experience, work hours, and work shifts of an extended duration. RESULTS: There were 52 near-miss events among patients cared for by the medical service (20 male patients, 32 females, mean age 72.6 +/- 9.7 years). The overall incidence of near-miss events when interns practiced during the first month of training vs. subsequent months was 1.6 (95%CI 0.77-2.9) vs. 0.6 (95%CI 0.44-0.83) cases per 100 intern-days at risk. The odds ratio for a near-miss event during the first month of intern training vs. subsequent months was 2.64 (95%CI 1.29-5.38). With respect to the interns' on-call shift schedule, one half of the near-miss episodes occurred during an intern's on-call days and another half of them during an extended on-call shift; none of the events occurred during a standard working shift. These events peaked in frequency when on-call interns had worked for 12-20 h. DISCUSSION: The first month of internship represents an error-prone period. The best interventions to reduce near-miss errors by recently graduated medical interns should be the subject of further research.

Hepatic steatosis in obese Chinese children.

THE AIMS OF OUR STUDY WERE: (1) to determine the prevalence of asymptomatic hepatic steatosis and presumed nonalcoholic steatohepatitis, in our local population of obese Chinese children referred for medical assessment; and (2) to assess the correlation between severity of ultrasonographic hepatic steatosis and degree of obesity, insulin resistance and serum biochemical abnormalities. DESIGN: Cross-sectional study. METHODS: In total, 84 obese children, 25 girls and 59 boys with median age and body mass index (BMI) of 12.0 years (interquartile range (IR): 9.5-14.0) and 30.3 kg/m(2) (IR: 27.1-33.4), respectively, referred for medical assessment were studied. All subjects underwent physical examination, anthropometric and dual energy X-ray absorptiometry (DEXA) scan measurements and real-time ultrasonographic (US) examination of the liver. Fasting blood samples were collected for the measurement of liver function, hepatitis status, levels of serum glucose and insulin and lipid profile. Degree of fatty infiltration of the liver was graded according to ultrasonic appearance of liver echotexture, liver-diaphragm differentiation in echo amplitude, hepatic echo penetration and clarity of hepatic blood vessels. RESULTS: All recruited subjects had no history of alcohol abuse and tests for Hepatitis B or C virus were negative. Thorough examination showed all of them to be in general good health without signs of chronic liver disease. Hepatic steatosis identified by defined ultrasonic appearances was diagnosed in 65 subjects (77%); 17 girls and 48 boys. The severity of fatty liver was positively related to anthropometric measurements including BMI, waist and hip circumference, subscapular skinfold thickness; insulin resistance markers [QUICKI and homeostasis model assessment (HOMA)], and hypertriglyceridaemia. Multvariate ordinal regression analysis showed that BMI and raised alanine aminotransferase (ALT) were positively associated with fatty liver. Combination of hepatic steatosis with raised ALT (presumptive NASH) was found in 19 subjects (24%). This group of patients had significantly higher waist hip ratio and conicity index compared to those with isolated hepatic steatosis. Boys with presumed NASH were also found to have significantly higher insulin resistance. CONCLUSION: Nonalcoholic fatty liver disease (NAFLD) was common among our cohort of obese children referred for medical assessment. The prevalence of simple steatosis and presumed NASH was 77 and 24%, respectively. The severity of US steatosis was positively correlated with BMI, raised ALT, insulin resistance and hypertryglyceridaemia. Ultrasonography being noninvasive and readily available could be used for the monitoring of the progression of hepatic steatosis. Further longitudinal studies are required to determine the natural disease progression and the role of insulin resistance and other factors in the pathophysiology of NAFLD.

Serum LD1 isoenzyme and blood lymphocyte subsets as prognostic indicators for severe acute respiratory syndrome.

BACKGROUND: The pathophysiology of severe acute respiratory syndrome (SARS) is at present poorly understood, but advanced age and serum total lactate dehydrogenase (LD) activity >300 U L(-1) have been associated with adverse clinical outcomes. Blood leucocytes and lymphocyte subsets were reported to decrease, respectively, in 47% and up to 100% of 38 patients in Beijing. However, their prognostic implications have not been thoroughly investigated. OBJECTIVE: To investigate serum total LD, LD isoenzymes, and other parameters including blood lymphocyte subsets as prognostic indicators in SARS patients for adverse clinical outcomes in terms of admission to intensive care unit (ICU) and death. DESIGN: Retrospective analysis. SUBJECTS AND METHODS: A total of 109 patients with a clinical diagnosis of SARS according to the modified World Health Organization case definition of SARS were recruited from two major acute hospitals in Hong Kong. They were either involved in the initial outbreak of SARS, or cases from the community outbreak of Amoy Gardens between 10 March and 5 May 2003. The clinical diagnosis was subsequently confirmed by serological test and/or molecular analysis. Serum total LD and LD isoenzyme activities, complete blood picture with total leucocyte count and differential counts, absolute counts of CD3+, CD4+, CD8+, natural killer cells and B lymphocytes were measured daily upon admission. Receiver operating characteristic curve analysis was used to determine and compare different cut-offs for various biochemical and immunological parameters at peak serum total LD concentration in predicting adverse clinical outcomes. RESULTS: Of a total of 109 patients, 41 were admitted to ICU and 42 died. Of 42 fatal patients, 24 died in ICU and 18 died in general medical wards. Age was found to be an independent prognostic indicator for death with an area under curve (AUC) of 0.96 [95% confidence interval (CI) = 0.90-0.99] but not for admission to ICU [AUC = 0.61 (CI = 0.51-0.70)]. Whilst serum total LD could only achieve AUC of 0.68 (CI = 0.59-0.77) for predicting death, LD1 isoenzyme was found to be the best biochemical prognostic indicator with AUC of 0.84 (CI = 0.75-0.90), sensitivity of 62% (CI = 46-76%), specificity of 93% (CI = 83-98%) at cut-off activity of > or =80 U L(-1). CD3+, CD4+, CD8+ and natural killer cell counts were promising immunological prognostic indicators for predicting admission to ICU with AUC of 0.94 (CI = 0.86-0.98), 0.91 (CI = 0.81-0.96), 0.93 (CI = 0.85-0.98), and 0.87 (CI = 0.76-0.94), respectively. CONCLUSIONS: Apart from age, serum LD1 activity was the best prognostic indicator for predicting death in patients with SARS compared with serum total LD activity, haemoglobin concentration, leucocyte and lymphocyte counts. Its release could possibly be from blood erythrocytes and body tissues other than the myocardium. Blood CD3+, CD4+, CD8+ and natural killer cell counts were found to be good prognostic indicators for predicting admission to ICU in patients with SARS compared with age, leucocyte count and LD isoenzymes. The suppressed CD3+, CD4+, CD8+, and natural killer cell counts were also implicated in the pathophysiology of SARS. Patients with increased serum LD1 should be closely monitored to ensure prompt management, and preparation for admission to ICU could be planned ahead for patients with suppressed lymphocyte subsets.

Plasma inflammatory cytokines and chemokines in severe acute respiratory syndrome.

Severe acute respiratory syndrome (SARS) is a recently emerged infectious disease caused by a novel coronavirus, but its immunopathological mechanisms have not yet been fully elucidated. We investigated changes in plasma T helper (Th) cell cytokines, inflammatory cytokines and chemokines in 20 patients diagnosed with SARS. Cytokine profile of SARS patients showed marked elevation of Th1 cytokine interferon (IFN)-gamma, inflammatory cytokines interleukin (IL)-1, IL-6 and IL-12 for at least 2 weeks after disease onset, but there was no significant elevation of inflammatory cytokine tumour necrosis factor (TNF)-alpha, anti-inflammatory cytokine IL-10, Th1 cytokine IL-2 and Th2 cytokine IL-4. The chemokine profile demonstrated significant elevation of neutrophil chemokine IL-8, monocyte chemoattractant protein-1 (MCP-1), and Th1 chemokine IFN-gamma-inducible protein-10 (IP-10). Corticosteroid reduced significantly IL-8, MCP-1 and IP-10 concentrations from 5 to 8 days after treatment (all P < 0.001). Together, the elevation of Th1 cytokine IFN-gamma, inflammatory cytokines IL-1, IL-6 and IL-12 and chemokines IL-8, MCP-1 and IP-10 confirmed the activation of Th1 cell-mediated immunity and hyperinnate inflammatory response in SARS through the accumulation of monocytes/macrophages and neutrophils.

Electrospray ionisation mass spectrometry: principles and clinical applications.

This mini-review provides a general understanding of electrospray ionisation mass spectrometry (ESI-MS) which has become an increasingly important technique in the clinical laboratory for structural study or quantitative measurement of metabolites in a complex biological sample. The first part of the review explains the electrospray ionisation process, design of mass spectrometers with separation capability, characteristics of the mass spectrum, and practical considerations in quantitative analysis. The second part then focuses on some clinical applications. The capability of ESI-tandem-MS in measuring bio-molecules sharing similar molecular structures makes it particularly useful in screening for inborn errors of amino acid, fatty acid, purine, pyrimidine metabolism and diagnosis of galactosaemia and peroxisomal disorders. Electrospray ionisation is also efficient in generating cluster ions for structural elucidation of macromolecules. This has fostered a new and improved approach (vs electrophoresis) for identification and quantification of haemoglobin variants. With the understanding of glycohaemoglobin structure, an IFCC reference method for glycohaemoglobin assay has been established using ESI-MS. It represents a significant advancement for the standardisation of HbA1c in diabetic monitoring. With its other applications such as in therapeutic drug monitoring, ESI-MS will continue to exert an important influence in the future development and organisation of the clinical laboratory service.