Clinical Applications: Carbohydrate Deficient Transferrin Online Training

Welcome to the Carbohydrate Deficient Transferring Online Training course.  Carbohydrate Deficient Transferrin Highly specific marker of chronic alcohol abuse Select Next to continue. This course was developed by: Steve Brimmer, Ph.D.   Upon successful completion of this course, you will be able to: Describe CDT and why it is measured   List other markers used to detect high alcohol intake   Describe how CDT is measured   State factors that can influence CDT measurements   Select Next to continue. Alcohol misuse results in 2.5 million deaths annually http://www.who.int/mediacentre/news/releases/2011/alcohol_20110211/en/index.html Nearly 4% of all deaths are related to alcohol Globally, 6.2% of all male deaths related to alcohol,   compared to 1.1% of female deaths Globally, 320,000 young people aged 15-29 years die annually from alcohol-related causes http://www.who.int/substance_abuse/publications/global_alcohol_report/msbgsruprofiles.pdf Alcohol consumption among adults, liters per capita   Czech Republic   14.97 Andorra               14.08  Estonia                13.77 Ireland                 13.39 France                 13.30 Croatia                 12.61 Austria                 12.60 Portugal               12.45 Hungary               12.27 Slovenia               12.19   US (42nd)              8.44 United States program to reduce the Alcohol Abuse 1980 per capita consumption 10.41 liters 2010 per capita consumption   8.44 liters 2009 Statistics:  Driving While Impaired One death every 48 minutes due to an alcohol-impaired driver 10,839 people in alcohol-related crashes On New Year’s Day, 178 people died in an alcohol-impaired driving accident 3 in 10 Americans will be involved in an alcohol-related crash http://www.edgarsnyder.com/drunk-driving/statistics.html Number of High School Seniors reporting alcohol use in last year decreased from ~90% to less than 70% since 1980 Percentage of High School Seniors consuming alcohol on a daily basis has dropped by more than 55% since 1980 http://www2.potsdam.edu/hansondj/AlcoholAbuse.html Unintentional injuries Violence is often involved Miscarriage and stillbirth Alcohol poisoning Liver disease: Alcoholic hepatitis, Cirrhosis Hepatitis C Gastrointestinal problems: Pancreatitis, Gastritis Cardiovascular problems: Myocardial infarction, cardiomyopathy, atrial fibrillation,  hypertension Neurological impairments and social problems Neurological: dementia, stroke and neuropathy Psychiatric: depression, anxiety, and suicide Social problems Harmful alcohol consumption has severe health & social consequences Estimated prevalence of problem drinking: 10 - 20% of patients in primary care settings 20 - 40% of patients in large urban hospitals1 30 - 40% of the total traffic fatalities2 Clinical signs of chronic drinking are unreliable Self-reporting underestimates2 Need for objective screening Decision limit depends on Harm from false-positive vs. risk of false-negative Prevalence of alcoholism in population tested 1 Allen JP , Military Medicine 2003 2 Alling C, Alcohol Clin Exp Res 2005 Screening for chronic heavy drinking Emergency rooms and intensive care units Identify patients in imminent danger of withdrawal Primary healthcare Decision-making based on role of alcohol as an etiological factor Motivating patients to change their drinking habits Monitoring patients after withdrawal Demonstrate beneficial effects of abstinence Enhance intervention in case of relapse Hannuksela M, Clin Chem Lab Med 2007 Identify individuals at risk for withdrawal Differentiate alcoholic from non-alcoholic liver diseases Follow-up patients after alcohol withdrawal Motivate patients to change drinking habits Seven European countries routinely use biomarkers as part of clinical evaluation to assess continued abstinence In Switzerland, Italy, and Austria, repeat offenders in therapy have biomarkers measured every quarter for a year to monitor abstinence. After one year, if treatment is successful, driver’s license is reinstated Bean. Alcohol Biomarkers. www.mlo-online.com 11-2005 Direct markers: Ethanol metabolites Ethyl Glucuronide Ethyl Sulfate Phosphatidyl ethanol Indirect markers: Metabolic reaction to ethanol GGT AST ALT MCV CDT Alcohol Biomarkers etg.samsha.advisory.pdf Sept 2006, volume 5 issue 4 Window of Assessment: how long biomarker may remain elevated once alcohol consumption ceases Alcohol Biomarkers etg.samsha.advisory.pdf Sept 2006, volume 5 issue 4   STRENGTH WEAKNESS GGT widely used standardized low specificity (elevated e.g. in all types of liver disease, obesity, with certain drugs) AST/ALT indicates excessive alcohol consumption too insensitive and nonspecific if used without other markers   STRENGTH WEAKNESS GGT widely used standardized low specificity (elevated e.g. in all types of liver disease, obesity, with certain drugs) AST/ALT indicates excessive alcohol consumption too insensitive and nonspecific if used without other markers MCV liver independent reflects toxic effect of alcohol low sensitivity & specificity slow response (RBC half-life = 3 months)   STRENGTH WEAKNESS GGT widely used standardized low specificity (elevated e.g. in all types of liver disease, obesity, with certain drugs) AST/ALT indicates excessive alcohol consumption too insensitive and nonspecific if used without other markers MCV liver independent reflects toxic effect of alcohol low sensitivity & specificity slow response (RBC half-life = 3 months) CDT high specificity return to normal after 2-4 weeks lack of standardization   Glycosylated iron transport protein Secreted by the liver 80 kD, single polypeptide chain with 670 amino acids 2 iron binding sites Multiple isoforms Half-life: 8 to10 days Asialo transferrin   (< 0.5 %)       Mono-sialo transferrin   (< 0.9 %)       Di-sialo transferrin   (< 2.5 %)       Tri-sialo transferrin   (4.5 – 9 %)       Tetra-sialo transferrin   (64 – 80 %)       Penta-sialo transferrin   (12 – 18 %)       Hexa-sialo transferrin   (1 – 3 %)       Asialo transferrin   (< 0.5 %)       Mono-sialo transferrin   (< 0.9 %)       Di-sialo transferrin   (< 2.5 %)       Tri-sialo transferrin   (4.5 – 9 %)       Tetra-sialo transferrin   (64 – 80 %)       Penta-sialo transferrin   (12 – 18 %)       Hexa-sialo transferrin   (1 – 3 %)       Asialo transferrin   (< 0.5 %)       Mono-sialo transferrin   (< 0.9 %)       Di-sialo transferrin   (< 2.5 %)       Tri-sialo transferrin   (4.5 – 9 %)       Tetra-sialo transferrin   (64 – 80 %)       Penta-sialo transferrin   (12 – 18 %)       Hexa-sialo transferrin   (1 – 3 %)       Asialo transferrin   (< 0.5 %)     CDT Mono-sialo transferrin   (< 0.9 %)     Di-sialo transferrin   (< 2.5 %)     Tri-sialo transferrin   (4.5 – 9 %)       Tetra-sialo transferrin   (64 – 80 %)       Penta-sialo transferrin   (12 – 18 %)       Hexa-sialo transferrin   (1 – 3 %)       CDT (Carbohydrate Deficient Transferrin) Increases in response to chronic heavy alcohol consumption (50 – 80 g ethanol per day over at least 2 consecutive weeks)   One bottle of wine 1.5 liters of beer 0.2 liters of alcohol Returns to normal with abstinence (half-life of ~ 15 days) Reference methods (defined by IFCC CDT Working group) HPLC Mass Spectrometry Other methods Iso-electric focusing Capillary electrophoresis Immunoassays Direct immunoassay Immunoassay after ion exchange separation step HPLC assay using visible detection at 470 nm separation takes around 25 minutes Oberrauch et al. Clinica Chimica Acta 2008:395:142-5. Oberrauch et al. Clinica Chimica Acta 2008:395:142-5. 2 2Delanghe et al., Clinical Chemistry 53:6 (2007) Sensitivity = 93.0 % Specificity = 97.0 % (relative to reference HPLC) Delanghe JR, Clin Chem 2007   Sensitivity and specificity relative to HPLC reference method*: %CDT threshold Specificity  (%) Sensitivity (%) 2.2 90 99 2.3 93 96 2.4 97 94 2.5 97 93 2.6 97 86   Sensitivity and specificity relative to HPLC reference method*: %CDT threshold Specificity  (%) Sensitivity (%) 2.2 90 99 2.3 93 96 2.4 97 94 2.5 97 93 2.6 97 86   Sensitivity and specificity relative to HPLC reference method*: %CDT threshold Specificity  (%) Sensitivity (%) 2.2 90 99 2.3 93 96 2.4 97 94 2.5 97 93 2.6 97 86   * HPLC cutoff = 1.7% disialo-transferrin Delanghe JR, Clin Chem 2007   2007 IFCC Working Group recommended (1) HPLC candidate reference method  (2) Disialotransferrin be the basis of CDT standardization %CDT be used Significant improvement by reducing variation due to conditions that   increase or decrease transferrin ↑ Transferrin  -- anemia, pregnancy and use of oral contraceptives ↓ Transferrin  -- inflammation and carcinoma   J. O. Jeppsson et al. Clin Chem Lab Med 2007:45(4):558-62.   2010: IFCC established a network of labs using candidate reference method IFCC established a candidate SRM in lyophilized human serum Immunoassay methods using anion exchange column withdrawn from market A. Helander et al. Clin Chem Lab Med 2010:48(11):1585-92. On the left, using method kit calibrators Inter-method CV = 18.9%   On the right, using calibrators standardized to SRM Inter-method CV = 5.5%   CDG syndrome (congenital disorder of glycosylation) Extremely rare inherited metabolic disorder Low transferrin levels (< 1.5 g/L) Seen in severe inflammation or liver disease ⇒ elevated %CDT in some samples Genetic transferrin D variants Interferes on electrophoresis methods Chronic active hepatitis, primary biliary cirrhosis Advanced liver fibrosis can decrease %CDT Recognition of patients with chronically high alcohol consumption Screening for harmful drinking Primary care setting Acute care in hospitals Workplace investigations Differential diagnosis:  alcohol induced vs. non-alcohol induced diseases Monitoring changes in alcohol consumption and monitoring abstinence Monitoring of alcohol abuse therapy Legal reasons, e.g. reissuing of driver license 28-year-old white male treated for anxiety Not responding to Paxil Initial evaluation: 2 year history of ruminative worry, poor sleep, irritability, poor concentration, and tension headaches He reported drinking 2 or 3 beers once or twice per week Medications was changed to Effexor and told to avoid alcohol because it can negatively impact sleep Cluver et al. J Addict Med. 2007:1(1):44-47. Symptoms unchanged after 2 months Follow up visit Parents expressed concern that he was drinking more than he reported Lab results: %CDT 2.9% (> 2.6% = heavy drinking) GGT 68    (upper reference limit = 45) Negative drug screen After he was told that his CDT result suggested 4 to 6 drinks daily, patient admitted to heavy drinking daily   Patient reluctantly agreed to start alcohol abuse program and was started on disulfiram Abstained from alcohol for 6 months %CDT reduced to 1.9% 53-year-old white male was sentenced by the court to alcohol counseling for a DWI conviction Had begun Alcoholics Anonymous three years earlier, considered himself to be an alcoholic “in recovery” Admitted that on the night of the arrest he had 6 drinks Reported increased depression, Prozac was increased Lab tests were normal, including %CDT of 1.7% Next appointment, he reported a substantial improvement in his depression and claimed continued abstinence from alcohol Laboratory testing was repeated: GGT within normal limits %CDT increased to 2.5% Results raised suspicion of heavy drinking One month later: GGT still within normal limits %CDT increased to 3.1% Next %CDT was 3.6% Next appointment, asked to bring life partner to corroborate abstinence Admitted to drinking regularly for 2 months Review of medical history showed MCV, transaminases, and GGT results always within normal limits, even during periods of heavy alcohol use Patient agreed to intensive treatment, including outpatient detoxification Cluver et al. J Addict Med. 2007:1(1):44-47. “CDT is currently the most specific marker of alcohol abuse” Niemelä O, Clin Chim Acta 2007