Metabolic Disorders Introduction Metabolism is the process your body uses to make energy from the food you eat. Your body can use this fuel right away, or it can store the energy in your body tissues, such as your liver, muscles and body fat. A metabolic disorder happens when abnormal chemical reactions in your body disrupt your metabolism. When this happens, you might have too much or too little of the substances that you need to stay healthy. This reference summary explains metabolic disorders. It talks about what metabolism is and the symptoms and causes of metabolic disorders. It also covers diagnosis and treatment of metabolic disorders. Metabolism Food is made up of proteins, carbohydrates and fats. Chemicals in your digestive system called enzymes break the food down into its individual components, which are used for energy. This process is known as metabolism. Your body uses sugars and fats for fuel. The fuel can be used right away. It can also be stored in your body s tissues, such as your liver, muscles and body fat. Your metabolism may be affected by a change in the balance of hormones or enzymes in your body. You might have too much of some substances or too little of other ones that you need to stay healthy. When this happens, chemical processes do not happen normally. Metabolic disorders fall into different categories, depending on which specific substance is affected. A metabolic disorder may happen if a substance builds up in harmful amounts because it cannot be broken down, or if the substance is too low or missing. Last reviewed: 08/14/2014 1
Symptoms and Causes Metabolic disorders may have many causes. Symptoms of metabolic disorders can depend on the cause. You can develop a metabolic disorder when some organs, such as your liver or pancreas: Become diseased. Do not work normally. Shut down. Organ problems may be caused by certain medical conditions, such as: Infections. Inflammation. Diseases such as hepatitis, diabetes or cirrhosis. High blood pressure. Liver Pancreas Hepatitis is a liver infection. It can cause jaundice and loss of appetite. If untreated, it can lead to inflammation and liver scarring. Diabetes is a disease in which the body cannot regulate the amount of sugar in the blood. Cirrhosis is the scarring of the liver. The scar tissue prevents the liver from working as it should, which can lead to life threatening complications. Organ problems may also be caused by lifestyle choices, including: Being overweight or obese. Drug and alcohol abuse. Eating a diet that is high in fat. When a metabolic disorder is caused by organ problems, symptoms may include: Blurry vision. Confusion, irritability or agitation. Fever. Loss of appetite and weight loss. Nausea. Poor wound healing. Tiredness and weakness. 2
More severe symptoms of organ problems may include: Abdominal pain, swelling or bloating. Frequent infections. Jaundice. Muscle loss. Vomiting or diarrhea. Jaundice is the yellowing of the skin and whites of the eyes. Metabolic disorders can lead to malnutrition. Malnutrition happens when your body does not have the right balance of nutrients. Even the lack of one vitamin can lead to malnutrition. A person with malnutrition may have no symptoms. But sometimes malnutrition can be so severe that it causes permanent harm to a person s body. Symptoms of malnutrition can include: Dizziness or fainting. Dry or scaly skin. Fatigue. Hair loss. Poor wound healing. Weight loss. Some metabolic diseases are inherited. This means that they are caused by defective genes and passed down through family members. Inherited metabolic diseases include: Alpha-1 antitrypsin deficiency. Cystic fibrosis. Galactosemia. Glycogen storage disease. Hemochromatosis. Wilson's disease. Alpha-1 antitrypsin deficiency leads to the damage of various organs in the body. Symptoms may include jaundice, fatigue, fluid in the abdomen, mental changes or gastrointestinal bleeding. 3
Cystic fibrosis is a disease that causes mucus in the body to become thick and sticky. This glue-like mucus builds up and causes problems in many of the body's organs. People who have cystic fibrosis can have serious breathing problems. They can also have problems with nutrition, digestion, growth and development. Galactosemia happens in newborn babies. It can result in damage to the liver, brain, kidneys and other organs. People with galactosemia cannot tolerate any amount of human or animal milk intake. Glycogen storage disease prevents the body from using and breaking down glycogen and carbohydrates normally. Hemochromatosis is the abnormally high absorption of iron by the intestinal tract. It causes too much iron to be stored in the liver, skin, pancreas, heart, joints and testes. Wilson s disease is a disorder in which too much copper builds up in the body. Diagnosis Your health care provider will perform a physical exam. He or she will ask you questions about your personal and family medical history. Blood tests can help your health care provider diagnose certain metabolic disorders. To diagnose specific conditions that affect different organs in the body, your health care provider may conduct: Blood tests. Imaging tests. A biopsy. Imaging tests include MRIs, CT-scans and ultrasounds. They allow health care providers to create detailed pictures of areas inside the body. A biopsy is the removal of cells or tissues for examination. The tissue may be studied under a microscope, or other tests may be done on the sample. Some inherited metabolic disorders can be diagnosed by routine screening tests done at birth. Others are identified only after a child or adult shows symptoms of a disorder. In some cases, children may have been misdiagnosed with cerebral palsy, autism or 4
other conditions whose symptoms can be similar to inherited metabolic disorders. These symptoms may include: Abnormal movements. An abnormally small head or brain. Birth defects. Developmental delays. Growth problems. Seizures. Treatment Because there are so many types of metabolic disorders, treatment recommendations may vary widely. Treatment may include: Dietary restrictions. Vitamins. Medicine. Surgery. If symptoms of a metabolic disorder are made worse by certain foods, your health care provider may recommend that you cut those foods out of your diet. If a metabolic disorder is caused by the lack of a certain substance, vitamins or medicine can replace the needed substance. Treatment for an inherited metabolic disorder depends on: The type and severity of the disorders. How much the disorder affects body or brain functions. Options for participating in a clinical trial. Certain inherited metabolic disorders may also increase risk of other conditions, such as heart, vision or hearing problems. If your health care provider thinks you are at risk of developing such problems, he or she may recommend regular heart, vision or hearing checkups. 5
For some inherited metabolic disorders, such as Tay-Sachs disease, there currently is no cure. Tay-Sachs disease is a rare and life threatening disease that affects the nervous system. It causes too much of a fatty substance to build up in the brain. In these cases, treatment includes supportive care for children and their families. Summary Metabolism is the process your body uses to make energy from the food you eat. Your body can use this fuel right away, or it can store the energy in your body tissues, such as your liver, muscles and body fat. A metabolic disorder happens when abnormal chemical reactions in your body disrupt your metabolism. Metabolic disorders fall into different categories, depending on which specific substance is affected. A metabolic disorder may happen if a substance builds up in harmful amounts because it cannot be broken down, or if the substance is too low or missing. Metabolic disorders may have many causes. Symptoms of metabolic disorders can depend on the cause. Some metabolic diseases are inherited. This means that they are caused by defective genes and passed down through family members. Because there are so many types of metabolic disorders, treatment recommendations may vary widely. Treatment may include: Dietary restrictions. Vitamins. Medicine. Surgery. Treatment for a metabolic disorder depends on: The type and severity of the disorders. How much the disorder affects body or brain functions. Options for participating in a clinical trial. 6