Transcript Thalassemia
Date of Presentation: September 23rd, 2014 Date of Sign-up: September 9th, 2014 Instructor: Dr. Jeffrey Henderson THALASSEMIA Chia-En Joanne Chang Amanda Chow Ju Pan (Harmony) Hsieh Linda Xi Yang WHAT IS THALASSEMIA? Source: http://thalassemia.com/images/thalassemia-word-cloud.png Sources: http://bio1151b.nicerweb.com/Locked/media/ch05/05_21gProteinHemoglobin-L.jpg http://3.bp.blogspot.com/-CeyaFwHVuMY/T28vDKkLxNI/AAAAAAAAACg/J-Mmi5xMncU/s1600/thalassemia.PNG http://www.map.ox.ac.uk/client_media/display/Pf_mean_2010/Pf_mean_2010_World.png CAUSES OF THALASSEMIA • Alpha-Thalassemia: • Deletion in one or more of the 2 alpha-globin genes (HBA1 and HBA2) of chromosome 16 Silent Carriers 1 gene deletion Hemoglobin H (HbH) disease 3 gene deletions Alpha-thalassemia trait 2 gene deletions Hemoglobin Bart hydrops fetalis syndrome All 4 genes deleted • Amount of mutation corresponds to severity of disease CAUSES OF THALASSEMIA • Beta-Thalassemia: • Point mutation in the beta-globin gene of chromosome 11 Thalassemia minor 1 gene mutation Thalassemia intermedia/major Both genes mutated • Amount of mutation corresponds to severity of disease SYMPTOMS Fussiness Fatigue Loss of Appetite Jaundice Paleness http://images.agoramedia.com/wte3.0/gcms/Fussy-Babies-300x300.jpg, http://atlascorrectionboise.com/wp-content/uploads/2014/01/fatiguedwoman.jpg, http://www.kidscenter.org/images/10415990/Jaundice-In-Newborn-Babies.jpg, http://images2.fanpop.com/image/photos/13300000/Edward-In-Eclipse-edward-cullen-13333892-2217-1599.jpg COMPLICATIONS Bone formation/puberty Frequent infections Liver failure Heart failure Enlarged Spleen http://bionews-tx.com/wp-content/uploads/2013/07/liver-failure.jpg http://blogs.independent.co.uk/wp-content/uploads/2012/06/090105101501-large.jpg, http://renovathx.com/wpcontent/uploads/2012/10/cropscisource_bh5041-31a1b4a59e737514549cca29e838f74f2dcf947a-s6-c30.jpg, http://drbcshah.com/wp-content/uploads/2013/02/spleen.jpg, Clinical Manifestation of [beta]-Thalassemia/Hemoglobin E Disease METHOD OF DIAGNOSIS • Before diagnosing a patient with thalassemia, the doctor will consider: • a) your family background • b) your ethnic group • c) whether your anemia is due to iron-deficiency instead of thalassemia • To diagnose thalassemias, doctors can use both: • 1) A (CBC) or complete blood count test to look for fewer than normal numbers of red blood cells, smaller red blood cells and low levels of hemoglobin. • 2) Hemoglobin test to look for mutated alpha or beta globin chains http://images.wisegeek.com/vials-of-blood.jpg http://www.familyholiday.net/wp-content/uploads/2012/05/Family-Tree-craft-Template-Ideas_15.jpg ALPHA-THALASSEMIA TREATMENTS • Silent carriers & alpha-thalassemia trait • No treatment required • Hemoglobin H disease • Red blood cell transfusion • Replenishes red blood cells lost due to hemolytic anemia • Folic acid supplements • Aids in production of normal red blood cells • Hemoglobin Bart hydrops fetalis syndrome • No current treatment known http://www.optimumchoices.com/images/Blood%20transfusion_.jpg http://pics1.ds-static.com/prodimg/17612/300.JPG BETA-THALASSEMIA TREATMENTS • Thalassemia minor/intermedia • No treatment required • Thalassemia major • Red blood cell transfusions • Replenishes red blood cells • Iron chelating • Removes excess iron https://www.blood.ca/centreapps/internet/uw_v502_mainengine.nsf/TopGeneric-en.gif http://www.solgar.com/pub/products/20111119115456_0680_T1_W275_H.jpeg BONE MARROW TRANSPLANT • Only known cure • Limitations: • Requires identical match for transplantation • Patient must have no high risk complication factors http://www.blood.ca/CentreApps/Internet/UW_V502_MainEngine.nsf/resources/landingpage/$file/onematch-big-logo.png PROGNOSIS: LIFESTYLE To keep a healthy and more normal lifestyle, people with thalassemia must: •1) Continue with blood transfusions or iron chelation medication treatments to avoid iron buildup, which can lead to organ failure and death •2) Get regular checkups for blood cell counts, iron levels, heart, liver and viral infection tests •3) Talk about feelings of stress, anxiety, fear or depression with your doctor, patient support groups, family and friends. •4) Look for a genetic counselor if you plan on having children http://www.pennmedicine.org/health_info/images/19449.jpg http://rhrealitycheck.wpengine.netdna-cdn.com/wp-content/uploads/2014/04/doctor-counseling-375x250.jpg RECENT RESEARCH 8 Thalassemia C D F T Children's Hospital & Research Center Oakland. "Welcome to Thalassemia.com." Northern California Comprehensive Thalassemia Center. N.p., n.d. Web. 12 Sept. 2014. <http://www.thalassemia.com/>. Cooley's Anemia Foundation. "About Thalassemia." Cooley's Anemia Foundation. N.p., n.d. Web. 13 Sept. 2014. <http://www.thalassemia.org/learn-about-thalassemia/about-thalassemia/>. Fucharoen, Suthat et al. "Clinical Manifestation of Beta-Thalassemia/Hemoglobin." Journal of Pediatric Hematology/Oncology 22.6 (2000): 552-557. Print. Galanello, Renzo, and Antonio Cao. "Alpha-thalassemia." Genetics in Medicine 13 (2011): 83-88. Print. Galanello, Renzo, and Raffaella Origa. "Beta-Thalassemia." Orphanet Journal of Rare Diseases 5.11 (2010): n. pag. OJRD. Web. 12 Sept. 2014. Gersten, Todd. "Hemolysis: MedlinePlus." Hemolysis . U.S. National Library of Medicine, n.d. Web. 12 Sept. 2014. <http://www.nlm.nih.gov/medlineplus/ency/article/002372.htm>. Leung, Kathryn . "Allogeneic Stem Cell Transplantation, Severe Homzygous 0/+Thalassemia or Sever Variants of Beta 0/+ Thalassemia, THALLO." ClinicalTrials.gov. US National Institutes of Health, n.d. Web. 16 Sept. 2014. <http://www.clinicaltrials.gov/ct2/show/NCT00578292?term=Thalassemia&rank=4>. Lucarelli, G., M. Andreani, and E. Angelucci. "The cure of thalassemia by bone marrow transplantation." Blood Reviews 16 (2002): 81-85. Print. Mednick, Lauren, et al. "Symptoms of depression and anxiety in patients with thalassemia: Prevalence and correlates in the thalassemia longitudinal cohort." American Journal of Hematology 85.10 (2010): 802-805. Print. National Center on Birth Defects and Developmental Disabilities. "Thalassemia ." National Center on Birth Defects and Developmental Disabilities . N.p., n.d. Web. 12 Sept. 2014. <http://www.cdc.gov/ncbddd/blooddisorders/documents/bbv_pnv_c0_1159_thalassemia_r 2mtr.pdf>. National Human Genome Research Institute. "Learning About Thalassemia." National Human Genome Research Institute. N.p., n.d. Web. 13 Sept. 2014. <http://www.genome.gov/10001221>. National Institute of Health. "What Are Thalassemias?." National Heart, Lung and Blood Institute. N.p., n.d. Web. 12 Sept. 2014. <http://www.nhlbi.nih.gov/health/health-topics/topics/thalassemia/>. S., Navaneetha Krishnan, Shaji G. , Ravalya P., and Nazia SK. "Management of Thalassemia." International Research Journal of Pharmacy 4.10 (2013): 1-3. Print. "Scientists advance a two-gene approach to curing beta-thalassemia." St Jude Children's Research Hospital. N.p., n.d. Web. 15 Sept. 2014. <http://www.stjude.org/stjude/v/index.jsp?vgnextoid=776e08eef1583210VgnVCM1000001e0215acRCRD&vgnextchannel=de2eecf652abe210V gnVCM1000001e0215acRCRD>. Thalassemia Foundation of Canada. "Clinical Trial Updates." Thalassemia Foundation of Canada . N.p., n.d. Web. 12 Sept. 2014. <http://www.thalassemia.ca/medical-updates/test-post-4/>. CITATIONS Thalassemia: genetic blood disorder causing an abnormally low functional hemoglobin or number of erythrocytes SUMMARY 2 major types of Thalassemia with subclasses within each type: oAlpha thalassemia - a defect in one or more of the alpha subunits. Occur most often in Southeast Asia, the Middle East, China, and African descent. Most prominently caused by deletion in either or both genes coding for the alpha globin subunits Inherited in an autosomal (Mendelian) recessive manner Has 4 forms of varying severity depending on presence of functioning alpha genes: 1) Silent carrier: one alpha globin gene deletion, generally normal phenotype 2) Alpha-thalassemia: one or two alpha globin gene deletions, deletions can be cis or trans 3) Hemoglobin H (HbH) disease: only one functional alpha globin gene present 4) Hemoglobin Bart hydrops fetalis syndrome: absence of all 4 alpha globin genes, fetuses are usually stillborn oBeta thalassemia - a defect in one or more of the beta subunits. Occur most often in Mediterranean origin, and to a lesser extent, Chinese, other Asians and African Americans Caused by point mutations in the beta-globin gene. Genes are inherited in an autosomal (Mendelian) recessive manner Has 3 forms of varying severity 1) Thalassemia minor: Heterozygous, one good beta gene and one defective. Usually no symptoms but can cause minor anemia. 2) Thalassemia intermedia: Homozygous, both defective beta gene. Less severe symptoms no blood transfusions required. 3) Thalassemia major: Homozygous, both defective beta gene. More severe symptoms, does require blood transfusion. Symptoms are severity-dependent and can include: fussiness, paleness, frequent infections, poor appetite, failure to thrive, failure to thrive, jaundice (yellowing of the skin and whites of the eyes), enlarged organs, malnourishment, and depression. Alpha thalassemia may also have bone growth problems at the cheeks, forehead and jaws; while patients with the most severe form of alpha thalassemia (hydrops fetalis) are stillborn or die shorty after being born. Patients looking to have children should talk to a genetic counselor Diagnosis: Doctors diagnose thalassemias using 1) a CBC(complete blood count test) to look for low RBC numbers, smaller than usual RBC and low hemoglobin as well as 2) a hemoglobin test to look for mutated alpha or beta globin chains. Treatment: Continue blood transfusions, iron chelation, regular checkups, and vitamin supplement intake. Cure: bone marrow transplant.