Sedentary Work Exerting up to 10 pounds (4.5 kg) of force occasionally and/or a negligible amount of force frequently or constantly to lift, carry, push, pull, or otherwise move objects, including the human body. Sedentary work involves sitting most of the time, but may involve walking or standing for brief periods of time. Jobs are sedentary if walking and standing are required only occasionally and other sedentary criteria are met.

Light Work Exerting up to 20 pounds (9.1 kg) of force occasionally and/or up to 10 pounds (4.5 kg) of force frequently, and/or negligible amount of force constantly to move objects. Physical demand requirements are in excess of those for Sedentary Work. Light Work usually requires walking or standing to a significant degree. However, if the use of the arm and/or leg controls requires exertion of forces greater than that for Sedentary Work and the worker sits most the time, the job is rated Light Work.

Medium Work Exerting up to 50 (22.7 kg) pounds of force occasionally, and/or up to 25 pounds (11.3 kg) of force frequently, and/or up to 10 pounds (4.5 kg) of forces constantly to move objects.

Heavy Work Exerting up to 100 pounds (45.4 kg) of force occasionally, and/or up to 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Very Heavy Work Exerting in excess of 100 pounds (45.4 kg) of force occasionally, and/or in excess of 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Job Classification

In most duration tables, five job classifications are displayed. These job classifications are based on the amount of physical effort required to perform the work. The classifications correspond to the Strength Factor classifications described in the United States Department of Labor's Dictionary of Occupational Titles. The following definitions are quoted directly from that publication.

Sedentary Work Exerting up to 10 pounds (4.5 kg) of force occasionally and/or a negligible amount of force frequently or constantly to lift, carry, push, pull, or otherwise move objects, including the human body. Sedentary work involves sitting most of the time, but may involve walking or standing for brief periods of time. Jobs are sedentary if walking and standing are required only occasionally and other sedentary criteria are met.

Light Work Exerting up to 20 pounds (9.1 kg) of force occasionally and/or up to 10 pounds (4.5 kg) of force frequently, and/or negligible amount of force constantly to move objects. Physical demand requirements are in excess of those for Sedentary Work. Light Work usually requires walking or standing to a significant degree. However, if the use of the arm and/or leg controls requires exertion of forces greater than that for Sedentary Work and the worker sits most the time, the job is rated Light Work.

Medium Work Exerting up to 50 (22.7 kg) pounds of force occasionally, and/or up to 25 pounds (11.3 kg) of force frequently, and/or up to 10 pounds (4.5 kg) of forces constantly to move objects.

Heavy Work Exerting up to 100 pounds (45.4 kg) of force occasionally, and/or up to 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Very Heavy Work Exerting in excess of 100 pounds (45.4 kg) of force occasionally, and/or in excess of 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Thalassemia


Related Terms

  • Alpha-thalassemia Major
  • Alpha-thalassemia Trait
  • Beta-thalassemia Intermedia
  • Beta-thalassemia Major
  • Beta-thalassemia Minor
  • Cooley's Anemia
  • Mediterranean Anemia

Differential Diagnosis

Specialists

  • Cardiologist, Cardiovascular Physician
  • Endocrinologist
  • Hematologist
  • Infectious Disease Internist

Comorbid Conditions

  • Bone-marrow-suppressing viruses
  • Cardiovascular disease
  • Diabetes mellitus
  • Endocrine disorders of the thyroid or adrenal glands
  • Sickle cell anemia

Factors Influencing Duration

Length of disability varies with the type of thalassemia and treatment. Laparoscopic splenectomy requires a shorter recovery than open abdominal surgery. The rate of recovery from bone marrow transplant is influenced by risk factors in place prior to the transplant, including high iron levels, liver disease, and heart disease.

Medical Codes

ICD-9-CM:
282.40 - Thalassemia, Unspecified
282.41 - Sickle-cell Thalassemia without Crisis; Microdrepanocytosis; Sickle-cell Thalassemia NOS; Thalassemia Hb-S Disease without Crisis
282.42 - Sickle-cell Thalassemia with Crisis; Sickle-cell Thalassemia with Vaso-occlusive Pain; Thalassemia Hb-S Disease with Crisis
282.43 - Alpha Thalassemia
282.44 - Beta Thalassemia
282.45 - Delta-beta Thalassemia
282.46 - Thalassemia Minor
282.47 - Hemoglobin E-beta Thalassemia

Overview

Thalassemia is a group of inherited disorders that result in abnormal production of hemoglobin, the protein inside red blood cells that carries oxygen. Each hemoglobin molecule contains four paired protein (globin) chains: two beta-globin chains and two alpha-globin chains.

In thalassemia, there is an inadequate production of one type of globin chain. Consequently, after all the available chains have paired up within the developing red blood cells, there is a shortage of normal hemoglobin and an accumulation of extra chains. The low hemoglobin level reduces the amount of oxygen that can be carried, and the extra chains make the cells fragile and prone to breaking apart (hemolysis). These abnormalities within the red blood cells lead to anemia.

The two main types of thalassemia are beta-thalassemia and alpha-thalassemia, which are categorized according to the type of globin under produced. The severity of the disease depends on the degree of globin shortage, which in turn depends on the genes an individual has inherited. In addition to the above, other, less common forms of the disease may occur, such as HbC, HbE, HbH, HbS, HbLepore.

The most common type of thalassemia is beta-thalassemia, in which beta-globin is under produced. The production of beta-globin is controlled by two genes, one inherited from each parent. There are three types of beta-thalassemia. Beta-thalassemia minor occurs when only one gene is defective and the remaining intact gene still produces a sufficient amount of beta-globin. There are typically no symptoms with this type of thalassemia. Beta-thalassemia major occurs when both genes are defective and no beta-globin is produced, resulting in severe anemia. Although both genes are defective, sometimes they produce an amount of beta-globin sufficient to prevent significant anemia. This condition is called beta-thalassemia intermedia.

In alpha-thalassemia, alpha-globin is under produced. Alpha-globin production is controlled by four genes, with each parent contributing two genes. Unlike in beta-thalassemia, the genes responsible for alpha-thalassemia are usually missing rather than defective. If only one or two genes are missing, typically there is no disease or symptoms. If three genes are missing, the reduction in alpha-globin is enough to cause significant anemia. This is known as hemoglobin H disease. Alpha-thalassemia major, a fatal condition, occurs when all four genes are missing. In this case no alpha-globin is produced.

Incidence and Prevalence: In the US, thalassemia infects 4 out of every 100,000 individuals, with the incidence growing during the 1990s because of increased immigration by Southeast Asians to North America. Thalassemia affects males and females equally. There is a growing incidence of the combined form of HbE and beta-thalassemia in the US. Because of the rising Asian population, this form of thalassemia (HbE/beta) will probably become the most common type here in the future.

Source: Medical Disability Advisor



Causation and Known Risk Factors

Thalassemia is associated with certain ethnic groups and is found most commonly among people of Mediterranean (Greek or Italian), Southeast Asian, Middle Eastern, or African descent. The burgeoning Asian population in California puts that state at increasing risk for the disease.

Source: Medical Disability Advisor



Diagnosis

History: An individual's symptoms vary according to the degree of anemia. The severe anemia of beta-thalassemia major causes extreme fatigue and shortness of breath. Beta-thalassemia intermedia may cause moderate symptoms, whereas hemoglobin H disease may cause moderate to severe symptoms. Patients with the alpha-thalassemia trait will express only a mild anemia, but the more virulent alpha-thalassemia major will result in the death of the newborn unless it is supported by a prenatal (intrauterine) blood transfusion.

Physical exam: Individuals with beta-thalassemia major often present with yellowing (jaundice) of the skin and eyes. An enlarged spleen (splenomegaly) may be discovered upon examination (palpation) of the abdomen. Bone deformities and growth retardation may result from an overgrowth of bone marrow. Individuals with beta-thalassemia intermedia and hemoglobin H disease may have more moderate variations of these physical signs. Individuals with beta-thalassemia minor may have splenomegaly. Symptoms related to anemia include exercise intolerance and heart murmur. Gout may be a presenting symptom in the presence of elevated uric acid levels (hyperuricemia).

Tests: A complete blood count reveals low hemoglobin and an elevated or near normal red blood cell count. A peripheral blood smear reveals abnormalities in red blood cells. The cells are paler than normal, an indication of the low level of hemoglobin per red blood cell. The cells are also smaller than normal (microcytosis). The size is reflected in a measurement called the mean corpuscular volume (MCV). Although the more severe forms of thalassemia have the most significant drops in hemoglobin levels, even mild forms have red blood cells with a below normal MCV.

Hemoglobin electrophoresis identifies and measures abnormal forms of hemoglobin and establishes the diagnosis of the beta-thalassemias, hemoglobin H disease and alpha-thalassemia major. DNA analysis of the genes responsible for alpha-globin production may be used to diagnose the alpha-thalassemias.

Source: Medical Disability Advisor



Treatment

Treatment for thalassemia includes blood transfusions, surgical removal of the spleen (splenectomy), and iron chelation therapy. Bone marrow transplant using marrow from a matched donor is the most aggressive treatment for thalassemia and the only one considered a cure. The purpose of the transplant is to replace genetically defective bone marrow cells with normal bone marrow cells that help produce normal amounts of both alpha- and beta-globin.

Blood transfusions are the primary treatment for beta-thalassemia major and are given frequently in order to maintain an acceptable hemoglobin level. Hemoglobin H disease may also require transfusions but not as commonly as beta-thalassemia major. In beta-thalassemia intermedia, transfusions are not required to maintain an acceptable hemoglobin level. An individual with this condition, however, is unstable and may over time or quite suddenly develop severe anemia. If transfusion is required, the condition is no longer considered beta-thalassemia intermedia but rather beta-thalassemia major. If the condition improves and no longer requires transfusions, the condition is again categorized as beta-thalassemia intermedia. Folate is usually given along with blood transfusions.

The spleen ordinarily removes red blood cells from circulation, so a splenectomy is often performed to keep red blood cells in circulation longer. This procedure may help reduce the need for transfusions in individuals with beta-thalassemia major and prevent transfusions completely in individuals with beta-thalassemia intermedia. The spleen may be removed through a large abdominal incision (open splenectomy) or through a flexible tube inserted in a small hole in the abdominal wall (laparoscopic splenectomy). Pneumococcal vaccine (vaccine against Streptococcus pneumoniae) should be given regularly to individuals who have had a splenectomy, since they are susceptible to infection from this bacterium.

The overgrowth of bone marrow associated with thalassemia causes increased iron absorption. This increased absorption, especially when combined with the iron added to the body through frequent transfusion, causes an overload of iron in body tissues such as the heart, liver, and glands (hematochromatosis). Iron chelation therapy using the drug deferoxamine removes this extra iron from the body. If the iron is not removed, heart failure and death will eventually result. Iron supplements and oxidative drugs such as sulfonamides should be avoided.

Source: Medical Disability Advisor



Prognosis

The predicted outcome of thalassemia depends on the severity of the disease and the degree to which an individual follows the appropriate prescribed treatment.

Individuals with beta-thalassemia major (the most severe form of thalassemia), can live into their fifties with blood transfusions, iron chelation therapy, and splenectomy. Without iron chelation therapy, however, survival is limited by the degree of iron overload within the heart, with death often occurring between the ages of 20 and 30. Bone marrow transplant with marrow from a matched donor offers a 54% to 90% survival rate for adults.

Almost all babies born with alpha-thalassemia major will die from anemia. There is, however, a small number who may survive after receiving prenatal (intrauterine) blood transfusions. The outlook for patients with HbH depends on the complications from blood transfusions, splenomegaly (splenic enlargement), or splenectomy (splenic removal) and the degree of anemia.

Source: Medical Disability Advisor



Complications

Iron overload (hematochromatosis) affects many bodily organs, including the heart, liver, pancreas, and thyroid, and may result in diabetes mellitus, hypothyroidism, heart failure, and even death.

Individuals with thalassemia are at increased risk for infection primarily due to iron overload. Many bacteria thrive when iron levels are high. Splenectomy also increases the risk of infection, particularly of bacterial pneumonia caused by Pneumococcus (Streptococcus pneumoniae).

Overgrowth of bone marrow may cause decreased bone density and bone fractures.

Source: Medical Disability Advisor



Ability to Work (Return to Work Considerations)

Time off for treatment may be needed. Blood transfusions are required at frequent intervals and require 3 to 4 hours per transfusion. Iron chelation therapy must be taken 5 to 7 times a week. Although the drug is administered through a pump placed under the skin, the process takes up to 12 hours and can cause discomfort. Because individuals with thalassemia may be more susceptible to infection and its complications, work exposure to infection should be limited. Depending on severity, anemia may necessitate reduced physical demands.

Source: Medical Disability Advisor



Failure to Recover

If an individual fails to recover within the expected maximum duration period, the reader may wish to consider the following questions to better understand the specifics of an individual's medical case.

Regarding diagnosis:

  • Is there a family history of thalassemia? Is individual of Mediterranean (Greek or Italian), Southeast Asian, Middle Eastern, or African descent?
  • Has individual had a viral infection that can cause the bone marrow to temporarily slow down or stop making new red blood cells?
  • Does individual report fatigue and shortness of breath? Is yellowing (jaundice) of the skin and eyes present?
  • On exam, was enlargement of the spleen (splenomegaly), bone deformities, or growth retardation noted?
  • Was a complete blood count (CBC) done to determine whether hemoglobin was low?
  • Did a peripheral blood smear reveal abnormalities in red blood cells?
  • Was hemoglobin electrophoresis required to assist with diagnosing the beta-thalassemias?
  • Was DNA analysis done to assist with diagnosing the alpha-thalassemias?
  • Was a diagnosis of alpha- or beta-thalassemia confirmed?

Regarding treatment:

  • Is individual a candidate for a bone marrow transplant? Is a matched donor available for the transplant? If not, does individual undergo regular blood transfusions?
  • Was removal of the spleen (splenectomy) done to keep red blood cells in circulation longer?
  • If individual has had a splenectomy, are pneumococcal vaccines given, as required?
  • Is chelation therapy done to remove excess iron from the body?
  • Does individual understand that, if not removed, excess iron eventually results in heart failure and death?
  • Are iron supplements and oxidative drugs such as sulfonamides avoided?
  • Have treatments successfully maintained adequate hemoglobin levels?

Regarding prognosis:

  • How severe is the disease?
  • Is individual compliant with all prescribed medical therapies?
  • Are there social, economic, or physical barriers to receiving prescribed medical treatment?
  • Has individual met the necessary requirements to receive a bone marrow transplant?
  • Has overgrowth of bone marrow occurred, causing decreased bone density resulting in bone fractures?
  • Has iron overload (hematochromatosis) affected heart, liver, pancreas, or thyroid? As a result, has individual developed diabetes mellitus, hypothyroidism, or heart failure?
  • Did a bacterial infection develop secondary to increased iron levels or to splenectomy?
  • How will complications be treated, and what is the expected outcome with treatment?
  • How will this disease and its treatments affect the daily activities of individual?

Source: Medical Disability Advisor



References

General

Yaish, Hassan M. "Thalassemia." eMedicine. Medscape. 23 May 2005 <http://emedicine.com/med/topic222.htm>.

Source: Medical Disability Advisor






Feedback
Send us comments, suggestions, corrections, or anything you would like us to hear. If you are not logged in, you must include your email address, in order for us to respond. We cannot, unfortunately, respond to every comment. If you are seeking medical advice, please contact your physician. Thank you!
Send this comment to:
Sales Customer Support Content Development
 
This publication is designed to provide accurate and authoritative information in regard to the subject matter covered. It is published with the understanding that the author, editors, and publisher are not engaged in rendering medical, legal, accounting or other professional service. If medical, legal, or other expert assistance is required, the service of a competent professional should be sought. We are unable to respond to requests for advice. Any Sales inquiries should include an email address or other means of communication.