lymphocytic

Leukemia is a term for cancers of the blood cells. Leukemia starts in blood-forming tissues such as the bone marrow. Your bone marrow makes the cells which will develop into white blood cells, red blood cells, and platelets. Each type of cell has a different job:

• White blood cells help your body fight infection
• Red blood cells deliver oxygen from your lungs to your tissues and organs
• Platelets help form clots to stop bleeding

When you have leukemia, your bone marrow makes large numbers of abnormal cells. This problem most often happens with white blood cells. These abnormal cells build up in your bone marrow and blood. They crowd out the healthy blood cells and make it hard for your cells and blood to do their work.

Acute lymphocytic leukemia is a type of acute leukemia. It's also called ALL and acute lymphoblastic leukemia. "Acute" means that it usually gets worse quickly if it's not treated. ALL is the most common type of cancer in children. It can also affect adults.

In ALL, the bone marrow makes too many lymphocytes, a type of white blood cell. These cells normally help your body fight infection. But in ALL, they are abnormal and cannot fight infection very well. They also crowd out the healthy cells, which can lead to infection, anemia, and easy bleeding. These abnormal cells can also spread to other parts of the body, including the brain and spinal cord.

ALL happens when there are changes in the genetic material (DNA) in bone marrow cells. The cause of these genetic changes is unknown. However, there are certain factors that raise your risk of ALL.

The factors that raise your risk of ALL include:

• Being male
• Being white
• Being over age 70
• Having had chemotherapy or radiation therapy
• Having been exposed to high levels of radiation
• Having certain genetic disorders, such as Down syndrome

The signs and symptoms of ALL include:

• Weakness or feeling tired
• Fever or night sweats
• Easy bruising or bleeding
• Petechiae, which are tiny red dots under the skin. They are caused by bleeding.
• Shortness of breath
• Weight loss or loss of appetite
• Pain in the bones or stomach
• Pain or feeling of fullness below the ribs
• Swollen lymph nodes - you may notice them as painless lumps in the neck, underarm, stomach, or groin
• Having had many infections

Your health care provider may use many tools to diagnose ALL and figure out which subtype you have:

• A physical exam
• A medical history
• Blood tests, such as
  • Complete blood count (CBC) with differential
  • Blood chemistry tests such as a basic metabolic panel (BMP), comprehensive metabolic panel (CMP), kidney function tests, liver function tests, and electrolyte panel
  • Blood smear
• Bone marrow tests. There are two main types - bone marrow aspiration and bone marrow biopsy. Both tests involve removing a sample of bone marrow and bone. The samples are sent to a lab for testing.
• Genetic tests to look for gene and chromosome changes

If you are diagnosed with ALL, you may have additional tests to see whether the cancer has spread. These include imaging tests and a lumbar puncture, which is a procedure to collect and test cerebrospinal fluid (CSF).

Treatments for ALL include:

• Chemotherapy
• Radiation therapy
• Chemotherapy with stem cell transplant
• Targeted therapy, which uses drugs or other substances that attack specific cancer cells with less harm to normal cells

Treatment is usually done in two phases:

• The goal of the first phase is to kill the leukemia cells in the blood and bone marrow. This treatment puts the leukemia into remission. Remission means that the signs and symptoms of cancer are reduced or have disappeared.
• The second phase is known as post-remission therapy. Its goal is to prevent a relapse (return) of the cancer. It involves killing any remaining leukemia cells that may not be active but could begin to regrow.

Treatment during both phases also usually includes central nervous system (CNS) prophylaxis therapy. This therapy helps prevent the spread of leukemia cells to the brain and spinal cord. It may be high dose chemotherapy or chemotherapy injected into the spinal cord. It also sometimes includes radiation therapy.

NIH: National Cancer Institute

Leukemia is a term for cancers of the blood cells. Leukemia starts in blood-forming tissues such as the bone marrow. Your bone marrow makes the cells which will develop into white blood cells, red blood cells, and platelets. Each type of cell has a different job:

• White blood cells help your body fight infection
• Red blood cells deliver oxygen from your lungs to your tissues and organs
• Platelets help form clots to stop bleeding

When you have leukemia, your bone marrow makes large numbers of abnormal cells. This problem most often happens with white blood cells. These abnormal cells build up in your bone marrow and blood. They crowd out the healthy blood cells and make it hard for your cells and blood to do their work.

Chronic lymphocytic leukemia (CLL) is a type of chronic leukemia. "Chronic" means that the leukemia usually gets worse slowly. In CLL, the bone marrow makes abnormal lymphocytes (a type of white blood cell). When the abnormal cells crowd out the healthy cells, it can lead to infection, anemia, and easy bleeding. The abnormal cells can also spread outside the blood to other parts of the body. CLL is one of the most common types of leukemia in adults. It often occurs during or after middle age. It is rare in children.

CLL happens when there are changes in the genetic material (DNA) in bone marrow cells. The cause of these genetic changes is unknown, so it's hard to predict who might get CLL. There are a few factors that might raise your risk.

It is hard to predict who will get CLL. There are a few factors that could raise your risk:

• Age - your risk goes up as you get older. Most people who are diagnosed with CLL are over 50.
• Family history of CLL and other blood and bone marrow diseases
• Racial/ethnic group - CLL is more common in whites than in people from other racial or ethnic groups
• Exposure to certain chemicals, including Agent Orange, a chemical that was used in the Vietnam War

In the beginning, CLL does not cause any symptoms. Later, you can have symptoms such as:

• Swollen lymph nodes - you may notice them as painless lumps in the neck, underarm, stomach, or groin
• Weakness or feeling tired
• Pain or a feeling of fullness below the ribs
• Fever and infection
• Easy bruising or bleeding
• Petechiae, which are tiny red dots under the skin. They are caused by bleeding.
• Weight loss for no known reason
• Drenching night sweats

Your health care provider may use many tools to diagnose CLL:

• A physical exam
• A medical history
• Blood tests, such as a complete blood count (CBC) with differential and blood chemistry tests. Blood chemistry tests measure different substances in the blood, including electrolytes, fats, proteins, glucose (sugar), and enzymes. Specific blood chemistry tests include a basic metabolic panel (BMP), a comprehensive metabolic panel (CMP), kidney function tests, liver function tests, and an electrolyte panel.
• Flow cytometry tests, which check for leukemia cells and identify which type of leukemia it is. The tests can be done on blood, bone marrow, or other tissue.
• Genetic tests to look for gene and chromosome changes

If you are diagnosed with CLL, you may have additional tests to see whether the cancer has spread. These include imaging tests and bone marrow tests.

Treatments for CLL include:

• Watchful waiting, which means that you don't get treatment right away. Your health care provider regularly checks to see if your signs or symptoms appear or change.
• Targeted therapy, which uses drugs or other substances that attack specific cancer cells with less harm to normal cells.
• Chemotherapy
• Radiation therapy
• Immunotherapy
• Chemotherapy with bone marrow or stem cell transplant

The goals of treatment are to slow the growth of the leukemia cells and to give you long periods of remission. Remission means that the signs and symptoms of cancer are reduced or have disappeared. The CLL may come back after remission, and you may need more treatment.

NIH: National Cancer Institute

Leukemia is a term for cancers of the blood cells. Leukemia starts in blood-forming tissues such as the bone marrow. Your bone marrow makes the cells which will develop into white blood cells, red blood cells, and platelets. Each type of cell has a different job:

• White blood cells help your body fight infection
• Red blood cells deliver oxygen from your lungs to your tissues and organs
• Platelets help form clots to stop bleeding

When you have leukemia, your bone marrow makes large numbers of abnormal cells. This problem most often happens with white blood cells. These abnormal cells build up in your bone marrow and blood. They crowd out the healthy blood cells and make it hard for your cells and blood to do their work.

There are different types of leukemia. Some types are acute (fast growing). They usually get worse quickly if they are not treated. Most childhood leukemias are acute:

• Acute lymphocytic leukemia (ALL), which is the most common type of leukemia in children and the most common cancer in children. In ALL, the bone marrow makes too many lymphocytes, a type of white blood cell.
• Acute myeloid leukemia (AML), which happens when bone marrow makes abnormal myeloblasts (a type of white blood cell), red blood cells, or platelets.

Other types of leukemia are chronic (slow growing). They usually get worse over a longer period of time. They are rare in children:

• Chronic lymphocytic leukemia (CLL), in which the bone marrow makes abnormal lymphocytes (a type of white blood cell). It is more common in teens than children.
• Chronic myeloid leukemia (CML), in which the bone marrow makes abnormal granulocytes (a type of white blood cell). It is very rare in children.

There are some other rare types of leukemia in children, including juvenile myelomonocytic leukemia (JMML).

Leukemia happens when there are changes in the genetic material (DNA) in bone marrow cells. The cause of these genetic changes is unknown. However, there are certain factors that raise the risk of childhood leukemia.

The factors that raise the risk of childhood leukemia include:

• Having a brother or sister, especially a twin, with leukemia
• Past treatment with chemotherapy
• Exposure to radiation, including radiation therapy
• Having certain genetic conditions, such as
  • Ataxia telangiectasia
  • Down syndrome
  • Fanconi anemia
  • Li-Fraumeni syndrome
  • Neurofibromatosis type 1

There are other factors that may raise the risk of getting one or more of the specific types of childhood leukemia.

Some of the symptoms of leukemia may include:

• Feeling tired
• Fever or night sweats
• Easy bruising or bleeding
• Weight loss or loss of appetite
• Petechiae, which are tiny red dots under the skin. They are caused by bleeding.

Other leukemia symptoms can be different from type to type. Chronic leukemia may not cause symptoms at first.

Your health care provider may use many tools to diagnose leukemia:

• A physical exam
• A medical history
• Blood tests, such as a complete blood count (CBC)
• Bone marrow tests. There are two main types - bone marrow aspiration and bone marrow biopsy. Both tests involve removing a sample of bone marrow and bone. The samples are sent to a lab for testing.
• Genetic tests to look for gene and chromosome changes

Once there is a diagnosis of leukemia, other tests may be done to see whether the cancer has spread. These include imaging tests and a lumbar puncture, which is a procedure to collect and test cerebrospinal fluid (CSF).

The treatments for leukemia depend on which type it is, how severe the leukemia is, the child's age, and other factors. Possible treatments might include:

• chemotherapy
• radiation therapy
• Chemotherapy with stem cell transplant
• Targeted therapy, which uses drugs or other substances that attack specific cancer cells with less harm to normal cells

Treatment for childhood leukemia is often successful. But the treatments can cause complications right away or later in life. Children who survived leukemia will need follow-up care the rest of their lives to watch for and treat any complications they may have.

NIH: National Cancer Institute

Leukemia is a term for cancers of the blood cells. Leukemia starts in blood-forming tissues such as the bone marrow. Your bone marrow makes the cells which will develop into white blood cells, red blood cells, and platelets. Each type of cell has a different job:

• White blood cells help your body fight infection
• Red blood cells deliver oxygen from your lungs to your tissues and organs
• Platelets help form clots to stop bleeding

When you have leukemia, your bone marrow makes large numbers of abnormal cells. This problem most often happens with white blood cells. These abnormal cells build up in your bone marrow and blood. They crowd out the healthy blood cells and make it hard for your cells and blood to do their work.

Chronic myeloid leukemia (CML) is a type of chronic leukemia. "Chronic" means that the leukemia usually gets worse slowly. In CML, the bone marrow makes abnormal granulocytes (a type of white blood cell). These abnormal cells are also called blasts. When the abnormal cells crowd out the healthy cells, it can lead to infection, anemia, and easy bleeding. The abnormal cells can also spread outside the blood to other parts of the body.

CML usually occurs in adults during or after middle age. It is rare in children.

Most people with CML have a genetic change called the Philadelphia chromosome. It's called that because researchers in Philadelphia discovered it. People normally have 23 pairs of chromosomes in each cell. These chromosomes contain your DNA (genetic material). In CML, part of the DNA from one chromosome moves to another chromosome. It combines with some DNA there, which creates a new gene called BCR-ABL. This gene causes your bone marrow to make an abnormal protein. This protein allows the leukemia cells to grow out of control.

The Philadelphia chromosome isn't passed from parent to child. It happens during your lifetime. The cause is unknown.

It is hard to predict who will get CML. There are a few factors that could raise your risk:

• Age - your risk goes up as you get older
• Gender - CML is slightly more common in men
• Exposure to high-dose radiation

Sometimes CML does not cause symptoms. If you do have symptoms, they can include:

• Feeling very tired
• Weight loss for no known reason
• Drenching night sweats
• Fever
• Pain or a feeling of fullness below the ribs on the left side

Your health care provider may use many tools to diagnose CML:

• A physical exam
• A medical history
• Blood tests, such as a complete blood count (CBC) with differential and blood chemistry tests. Blood chemistry tests measure different substances in the blood, including electrolytes, fats, proteins, glucose (sugar), and enzymes. Specific blood chemistry tests include a basic metabolic panel (BMP), a comprehensive metabolic panel (CMP), kidney function tests, liver function tests, and an electrolyte panel.
• Bone marrow tests. There are two main types - bone marrow aspiration and bone marrow biopsy. Both tests involve removing a sample of bone marrow and bone. The samples are sent to a lab for testing.
• Genetic tests to look for gene and chromosome changes, including tests to look for the Philadelphia chromosome

If you are diagnosed with CML, you may have additional tests such as imaging tests to see whether the cancer has spread.

CML has three phases. The phases are based on how much the CML has grown or spread:

• Chronic phase, where less than 10% of cells in the blood and bone marrow are blast cells (leukemia cells). Most people are diagnosed in this phase, and many do not have symptoms. Standard treatment usually helps in this phase.
• Accelerated phase, 10% to 19% of the cells in the blood and bone marrow are blast cells. In this phase, people often have symptoms and standard treatment may not be as effective as in the chronic phase.
• Blastic phase, where 20% or more of the cells in the blood or bone marrow are blast cells. The blast cells have spread to other tissues and organs. If you have tiredness, fever, and an enlarged spleen during the blastic phase, it is called a blast crisis. This phase is harder to treat.

There are several different treatments for CML:

• Targeted therapy, which uses drugs or other substances that attack specific cancer cells with less harm to normal cells. For CML, the drugs are tyrosine kinase inhibitors (TKIs). They block tyrosine kinase, which is an enzyme that causes your bone marrow to make too many blasts.
• Chemotherapy
• Immunotherapy
• High-dose chemotherapy with stem cell transplant
• Donor lymphocyte infusion (DLI). DLI is a treatment that may be used after a stem cell transplant. It involves giving you an infusion (into your bloodstream) of healthy lymphocytes from the stem cell transplant donor. Lymphocytes are a type of white blood cell. These donor lymphocytes may kill the remaining cancer cells.
• Surgery to remove the spleen (splenectomy)

Which treatments you get will depend on which phase you are in, your age, your overall health, and other factors. When the signs and symptoms of CML are reduced or have disappeared, it is called remission. The CML may come back after remission, and you may need more treatment.

NIH: National Cancer Institute

Leukemia is a term for cancers of the blood cells. Leukemia starts in blood-forming tissues such as the bone marrow. Your bone marrow makes the cells which will develop into white blood cells, red blood cells, and platelets. Each type of cell has a different job:

• White blood cells help your body fight infection
• Red blood cells deliver oxygen from your lungs to your tissues and organs
• Platelets help form clots to stop bleeding

When you have leukemia, your bone marrow makes large numbers of abnormal cells. This problem most often happens with white blood cells. These abnormal cells build up in your bone marrow and blood. They crowd out the healthy blood cells and make it hard for your cells and blood to do their work.

There are different types of leukemia. Which type of leukemia you have depends on the type of blood cell that becomes cancer and whether it grows quickly or slowly.

The type of blood cell could be:

• Lymphocytes, a type of white blood cell
• Myeloid cells, immature cells that become white blood cells, red blood cells, or platelets

The different types can grow quickly or slowly:

• Acute leukemia is fast growing. It usually gets worse quickly if it's not treated.
• Chronic leukemia is slow growing. It usually gets worse over a longer period of time.

The main types of leukemia are:

• Acute lymphocytic leukemia (ALL), which is the most common type of cancer in children. It can also affect adults.
• Acute myeloid leukemia (AML), which is more common in older adults but can also affect children
• Chronic lymphocytic leukemia (CLL), which is one of the most common types of leukemia in adults. It often occurs during or after middle age.
• Chronic myeloid leukemia (CML), which usually occurs in adults during or after middle age

Leukemia happens when there are changes in the genetic material (DNA) in bone marrow cells. The cause of these genetic changes is unknown.

For the specific types, there are different factors which can raise your risk of getting that type. Overall, your risk of leukemia goes up as you age. It is most common over age 60.

Some of the symptoms of leukemia may include:

• Feeling tired
• Fever or night sweats
• Easy bruising or bleeding
• Weight loss or loss of appetite
• Petechiae, which are tiny red dots under the skin. They are caused by bleeding.

Other leukemia symptoms can be different from type to type. Chromic leukemia may not cause symptoms at first.

Your health care provider may use many tools to diagnose leukemia:

• A physical exam
• A medical history
• Blood tests, such as a complete blood count (CBC)
• Bone marrow tests. There are two main types - bone marrow aspiration and bone marrow biopsy. Both tests involve removing a sample of bone marrow and bone. The samples are sent to a lab for testing.
• Genetic tests to look for gene and chromosome changes

Once the provider makes a diagnosis, there may be additional tests to see whether the cancer has spread. These include imaging tests and a lumbar puncture, which is a procedure to collect and test cerebrospinal fluid (CSF).

The treatments for leukemia depend on which type you have, how severe the leukemia is, your age, your overall health, and other factors. Some possible treatments might include:

• Chemotherapy
• Radiation therapy
• Chemotherapy with stem cell transplant
• Targeted therapy, which uses drugs or other substances that attack specific cancer cells with less harm to normal cells

NIH: National Cancer Institute

Your immune system is a complex network of cells, tissues, and organs. Together they help the body fight infections and other diseases.

When germs such as bacteria or viruses invade your body, they attack and multiply. This is called an infection. The infection causes the disease that makes you sick. Your immune system protects you from the disease by fighting off the germs.

The immune system has many different parts, including:

• Your skin, which can help prevent germs from getting into the body
• Mucous membranes, which are the moist, inner linings of some organs and body cavities. They make mucus and other substances which can trap and fight germs.
• White blood cells, which fight germs
• Organs and tissues of the lymph system, such as the thymus, spleen, tonsils, lymph nodes, lymph vessels, and bone marrow. They produce, store, and carry white blood cells.

Your immune system defends your body against substances it sees as harmful or foreign. These substances are called antigens. They may be germs such as bacteria and viruses. They might be chemicals or toxins. They could also be cells that are damaged from things like cancer or sunburn.

When your immune system recognizes an antigen, it attacks it. This is called an immune response. Part of this response is to make antibodies. Antibodies are proteins that work to attack, weaken, and destroy antigens. Your body also makes other cells to fight the antigen.

Afterwards, your immune system remembers the antigen. If it sees the antigen again, it can recognize it. It will quickly send out the right antibodies, so in most cases, you don't get sick. This protection against a certain disease is called immunity.

There are three different types of immunity:

• Innate immunity is the protection that you are born with. It is your body's first line of defense. It includes barriers such as the skin and mucous membranes. They keep harmful substances from entering the body. It also includes some cells and chemicals which can attack foreign substances.
• Active immunity, also called adaptive immunity, develops when you are infected with or vaccinated against a foreign substance. Active immunity is usually long-lasting. For many diseases, it can last your entire life.
• Passive immunity happens when you receive antibodies to a disease instead of making them through your own immune system. For example, newborn babies have antibodies from their mothers. People can also get passive immunity through blood products that contain antibodies. This kind of immunity gives you protection right away. But it only lasts a few weeks or months.

Sometimes a person may have an immune response even though there is no real threat. This can lead to problems such as allergies, asthma, and autoimmune diseases. If you have an autoimmune disease, your immune system attacks healthy cells in your body by mistake.

Other immune system problems happen when your immune system does not work correctly. These problems include immunodeficiency diseases. If you have an immunodeficiency disease, you get sick more often. Your infections may last longer and can be more serious and harder to treat. They are often genetic disorders.

There are other diseases that can affect your immune system. For example, HIV is a virus that harms your immune system by destroying your white blood cells. If HIV is not treated, it can lead to AIDS (acquired immunodeficiency syndrome). People with AIDS have badly damaged immune systems. They get an increasing number of severe illnesses.

Lymphoma is a cancer of a part of the immune system called the lymph system. There are many types of lymphoma. One type is Hodgkin disease. The rest are called non-Hodgkin lymphomas.

Non-Hodgkin lymphomas begin when a type of white blood cell, called a T cell or B cell, becomes abnormal. The cell divides again and again, making more and more abnormal cells. These abnormal cells can spread to almost any other part of the body. Most of the time, doctors don't know why a person gets non-Hodgkin lymphoma. You are at increased risk if you have a weakened immune system or have certain types of infections.

Non-Hodgkin lymphoma can cause many symptoms, such as :

• Swollen, painless lymph nodes in the neck, armpits or groin
• Unexplained weight loss
• Fever
• Soaking night sweats
• Coughing, trouble breathing or chest pain
• Weakness and tiredness that don't go away
• Pain, swelling or a feeling of fullness in the abdomen

Your doctor will diagnose lymphoma with a physical exam, blood tests, a chest x-ray, and a biopsy. Treatments include chemotherapy, radiation therapy, targeted therapy, biological therapy, or therapy to remove proteins from the blood. Targeted therapy uses drugs or other substances that attack specific cancer cells with less harm to normal cells. Biologic therapy boosts your body's own ability to fight cancer. If you don't have symptoms, you may not need treatment right away. This is called watchful waiting.

NIH: National Cancer Institute

Your blood is living tissue made up of liquid and solids. The liquid part, called plasma, is made of water, salts and protein. Over half of your blood is plasma. The solid part of your blood contains red blood cells, white blood cells and platelets.

Blood disorders affect one or more parts of the blood and prevent your blood from doing its job. They can be acute or chronic. Many blood disorders are inherited. Other causes include other diseases, side effects of medicines, and a lack of certain nutrients in your diet.

Types of blood disorders include:

• Platelet disorders, excessive clotting, and bleeding problems, which affect how your blood clots
• Anemia, which happens when your blood does not carry enough oxygen to the rest of your body
• Cancers of the blood, such as leukemia and myeloma
• Eosinophilic disorders, which are problems with one type of white blood cell.

Your colon, also known as the large intestine, is part of your digestive system. It's a long, hollow tube at the end of your digestive tract where your body makes and stores stool. Many disorders affect the colon's ability to work properly. Some of these include:

• Colorectal cancer
• Colonic polyps - extra tissue growing in the colon that can become cancerous
• Ulcerative colitis - ulcers of the colon and rectum
• Diverticulitis - inflammation or infection of pouches in the colon
• Irritable bowel syndrome - an uncomfortable condition causing abdominal cramping and other symptoms

Treatment for colonic diseases varies greatly depending on the disease and its severity. Treatment may involve diet, medicines and in some cases, surgery.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases

HIV stands for human immunodeficiency virus. HIV harms your immune system by destroying a type of white blood cell that helps your body fight infection. This puts you at risk for other infections and diseases.

AIDS stands for acquired immunodeficiency syndrome. It is the final stage of infection with HIV. It happens when the body's immune system is badly damaged because of the virus. Not everyone with HIV develops AIDS.

HIV is spread through certain body fluids from a person who has HIV. This can happen:

• By having unprotected vaginal or anal sex with a person who has HIV. "Unprotected" means not using condoms or medicine to treat or prevent HIV. This is the most common way that it spreads.
• By sharing drug needles.
• Through contact with the blood of a person with HIV.
• From mother to baby during pregnancy, childbirth, or breastfeeding.

Anyone can get HIV, but certain groups have a higher risk of getting it:

• People who have another sexually transmitted disease (STD). Having an STD can increase your risk of getting or spreading HIV.
• People who inject drugs with shared needles.
• Gay and bisexual men.
• Black/African Americans and Hispanic/Latino Americans. They make up a higher proportion of new HIV diagnoses and people with HIV, compared to other races and ethnicities.
• People who engage in risky sexual behaviors, such as not using condoms or medicine to prevent or treat HIV.

Factors such as stigma, discrimination, income, education, and geographic region can also affect people's risk for HIV.

The first signs of HIV infection may be flu-like symptoms:

• Fever
• Chills
• Rash
• Night sweats (heavy sweating during sleep)
• Muscle aches
• Sore throat
• Fatigue
• Swollen lymph nodes
• Mouth ulcers

These symptoms may come and go within two to four weeks. This stage is called acute HIV infection.

If the infection is not treated, it becomes chronic HIV infection. Often, there are no symptoms during this stage. If it is not treated, eventually the virus will weaken your body's immune system. Then the infection will progress to AIDS. This is the late stage of HIV infection. Because your immune system is badly damaged, your body cannot fight off other infections, called opportunistic infections (OIs). OIs are infections that happen more frequently or are more severe in people who have weakened immune systems.

Some people may not feel sick during the earlier stages of HIV infection. So the only way to know for sure whether you have HIV is to get tested.

A blood test can tell if you have HIV infection. Your health care provider can do the test, or you can use a home testing kit. You can also use the CDC Testing Locator to find free testing sites.

There is no cure for HIV infection, but it can be treated with medicines. This is called antiretroviral therapy (ART). ART can make HIV infection a manageable chronic condition. It also reduces the risk of spreading the virus to others.

Most people with HIV live long and healthy lives if they get ART as soon as possible and stay on it. It's also important to take care of yourself. Making sure that you have the support you need, living a healthy lifestyle, and getting regular medical care can help you enjoy a better quality of life.

You can reduce the risk of getting or spreading HIV by:

• Getting tested for HIV.
• Choosing less risky sexual behaviors. This includes limiting the number of sexual partners you have and using latex condoms every time you have sex. If your or your partner is allergic to latex, you can use polyurethane condoms.
• Getting tested and treated for sexually transmitted diseases (STDs).
• Not injecting drugs.
• Talking to your health care provider about medicines to prevent HIV:
  • PrEP (pre-exposure prophylaxis) is for people who don't already have HIV but are at very high risk of getting it. PrEP is daily medicine that can reduce this risk.
  • PEP (post-exposure prophylaxis) is for people who have possibly been exposed to HIV. It is only for emergency situations. PEP must be started within 72 hours after a possible exposure to HIV.

NIH: National Institutes of Health