Aplastic anemia is a rare but serious blood disorder. If you have it, your bone marrow doesn't make enough new blood cells. It happens when there is damage to stem cells inside your bone marrow. There are different types of aplastic anemia, including Fanconi anemia.

The causes of aplastic anemia can include:

• Autoimmune disorders, which are the most common cause
• Certain inherited gene changes, such as the one that can cause Fanconi anemia
• Toxic substances, such as pesticides, arsenic, and benzene
• Radiation therapy and chemotherapy for cancer
• Certain medicines
• Viral infections such as hepatitis, Epstein-Barr virus, or HIV
• Pregnancy

In many people, the cause is unknown. This is called idiopathic aplastic anemia.

Aplastic anemia can develop suddenly or slowly. It can be mild or severe. The symptoms of aplastic anemia can include:

• Fatigue
• Weakness
• Dizziness
• Shortness of breath
• Easy bruising or bleeding

Aplastic anemia can cause other problems, including frequent infections and bleeding. It raises your risk of developing a serious blood disorder.

If not treated, aplastic anemia can also lead to heart problems such as an arrhythmia (a problem with the rate or rhythm of your heartbeat), an enlarged heart, or heart failure.

To find out if you have aplastic anemia, your doctor will:

• Take your medical and your family medical histories
• Do a physical exam
• Order tests, such as tests to check if you have low numbers of cells in your bone marrow and blood

If you have aplastic anemia, your doctor will create a treatment plan for you. The plan will be based on how severe the anemia is and what is causing it. Treatments can include:

• Blood transfusions
• Blood and marrow stem cell transplants
• Medicines to suppress your immune system

Because of the risk of blood disorders, your doctor will monitor your condition and screen you for blood disorders regularly.

NIH: National Heart, Lung, and Blood Institute

Arsenic is a natural element found in soil and minerals. Arsenic compounds are used to preserve wood, as pesticides, and in some industries. Arsenic can get into air, water, and the ground from wind-blown dust. It may also get into water from runoff.

You may be exposed to arsenic by:

• Taking in small amounts in food, drinking water, or air
• Breathing sawdust or burning smoke from arsenic-treated wood
• Living in an area with high levels of arsenic in rock
• Working in a job where arsenic is made or used

Exposure to arsenic can cause many health problems. Being exposed to low levels for a long time can change the color of your skin. It can cause corns and small warts. Exposure to high levels of arsenic can cause death.

Agency for Toxic Substances Disease Registry

People can lose all or part of an arm or leg for a number of reasons. Common ones include:

• Circulation problems from atherosclerosis or diabetes. They may cause you to need an amputation.
• Traumatic injuries, including from traffic accidents and military combat
• Cancer
• Birth defects

If you are missing an arm or leg, an artificial limb can sometimes replace it. The device, which is called a prosthesis, can help you to perform daily activities such as walking, eating, or dressing. Some artificial limbs let you function nearly as well as before.

Aspergillosis is a disease caused by a fungus (or mold) called Aspergillus. The fungus is very common in both indoors and outdoors. Most people breathe in the spores of the fungus every day without being affected. But some people get the disease. It usually occurs in people with lung diseases or weakened immune systems.

There are different kinds of aspergillosis. One kind is allergic bronchopulmonary aspergillosis (also called ABPA). Symptoms of ABPA include wheezing and coughing. ABPA can affect healthy people but it is most common in people with asthma or cystic fibrosis.

Another kind is invasive aspergillosis, which damages tissues in the body. It usually affects the lungs. Sometimes it can also cause infection in other organs and spread throughout the body. It affects people who have immune system problems, such as people who have had a transplant, are taking high doses of steroids, or getting chemotherapy for some cancers.

Your doctor might do a variety of tests to make the diagnosis, including a chest x-ray, CT scan of the lungs, and an examination of tissues for signs of the fungus. Treatment is with antifungal drugs. If you have ABPA, you may also take steroids.

Centers for Disease Control and Prevention

Ataxia-telangiectasia (A-T) is a rare, inherited disease. It affects the nervous system, immune system, and other body systems. Symptoms appear in young children, usually before age 5. They include:

• Ataxia - trouble coordinating movements
• Poor balance
• Slurred speech
• Tiny, red spider veins, called telangiectasias, on the skin and eyes
• Lung infections
• Delayed physical and sexual development

People with A-T have an increased risk of developing diabetes and cancers, especially lymphoma and leukemia. Although it affects the brain, people with A-T usually have normal or high intelligence.

A-T has no cure. Treatments might improve some symptoms. They include injections to strengthen the immune system, physical and speech therapy, and high-dose vitamins.

NIH: National Institute of Neurological Disorders and Stroke