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Bronchitis

Bronchitis is an inflammation of the lining of the bronchial tubes, the airways that connect the trachea to the lungs. This delicate, mucus-producing lining covers and protects the respiratory system, the organs and tissues involved in breathing. When a person has bronchitis, it may be harder for air to pass in and out of the lungs than it normally would, the tissues become irritated and more mucus is produced. The most common symptom of bronchitis is a cough.

Bronchitis can be acute or chronic. An acute medical condition comes on quickly and can cause severe symptoms, but it lasts only a short time (no longer than a few weeks). Acute bronchitis is most often caused by one of a number of viruses that can infect the respiratory tract and attack the bronchial tubes. Chronic bronchitis, on the other hand, can be mild to severe and is longer lasting - from several months to years. People who have chronic bronchitis are more susceptible to bacterial infections of the airway and lungs, like pneumonia.

Acute bronchitis often starts with a dry, annoying cough that is triggered by the inflammation of the lining of the bronchial tubes. Other syrnptoms may include: cough that may bring up thick white, yellow, or greenish mucus, headache, generally feeling ill, chills, fever and shortness of breath, soreness or a feeling of tightness in the chest, wheezing (a whistling or hissing sound with breathing)

Smoking and being around tobacco smoke, chemical fumes, and other air pollutants for long periods of time puts a person at risk for developing chronic bronchitis.

Some people who seem to have repeated bouts of bronchitis - with coughing, wheezing, and shortness of breath - may actually have asthma.

If a doctor thinks you may have bronchitis, he or she will examine you and listen to your chest with a stethoscope for signs of wheezing and congestion.

In addition to this physical examination, the doctor will ask you about any concerns and symptoms you have, your past health, your family's health,, any medications you're taking, any allergies you may have, and other issues (including whether you smoke). This is called the medical history. Your doctor may order a chest X-ray to rule out a condition like pneumonia, and may sometimes order a breathing test to rule out asthma.

Because acute bronchitis is most often caused by a virus, the doctor may not prescribe an antibiotic (antibiotics only work against bacteria, not viruses).

The doctor will recommend that you drink lots of fluids, get plenty of rest, and may suggest using an over-the-counter or prescription cough medicine to relieve your symptoms as you recover.

If you have chronic bronchitis, the goal is to reduce your exposure to whatever is irritating your bronchial tubes. For people who smoke, that means quitting!

If you have bronchitis and don't smoke, try to avoid exposure to second-hand smoke.

Tuberculosis or ТВ

Tuberculosis or ТВ (short for tubercles bacillus) is a common and often deadly infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis in humans. Tuberculosis usually attacks the lungs but can also affect other parts of the body. It is spread through the air; when people who have the disease cough, sneeze, or spit. Most infections in humans result in an asymptomatic, latent infection, and about one in ten latent infections eventually progresses to active disease, which, if left untreated, kills more than 50% of its victims.

The classic symptoms are a chronic cough with blood-tinged sputum, fever, night sweats, and weight loss. Infection of other organs causes a wide range of symptoms. Diagnosis relies on radiology (commonly chest X-rays), a tuberculin skin test, blood tests, as well as microscopic examination and microbiological culture of bodily fluids. Treatment is difficult and requires long courses of multiple antibiotics. Contacts are also screened and treated if necessary. Antibiotic resistance is a growing problem in (extensively) multi-drug-resistant tuberculosis. Prevention relies on screening programs and vaccination, usually with Bacillus Calmette-Guerin vaccine. When the disease becomes active, 75% of the cases are pulmonary ТВ, that is, ТВ in the lungs. Symptoms include chest pain, coughing up blood, and a productive, prolonged cough for more than three weeks. Systemic symptoms include fever, chills, night sweats, appetite loss, weight loss, pallor, and often a tendency to fatigue very easily.

In the other 25% of active cases, the infection moves from the lungs, causing other kinds of ТВ, collectively denoted extrapulmonary tuberculosis. This occurs more commonly in immunosuppressed persons and young children. Extrapulmonary infection sites include the pleura in tuberculosis pleurisy, the central nervous system in meningitis, the lymphatic system in scrofula of the neck, the genitourinary system in urogenital tuberculosis, and bones and joints in Pott's disease of the spine.

A third of the world's population is thought to be infected with M. tuberculosis, and new infections occur at a rate of about one per second. The proportion of people who become sick with tuberculosis each year is stable or falling worldwide but, because of population growth, the absolute number of new cases is still increasing. In addition, more people in the developed world are contracting tuberculosis because their immune systems are compromised by immunosuppressive drugs, substance abuse, or AIDS.

Thrombosis

Thrombosis is the clotting of blood within a blood vessel. It occurs when a blood clot blocks a vein or an artery, obstructing or stopping the flow of blood.

Thrombosis can occur anywhere in the body's bloodstream. There are two main types of thrombosis:

• venous thrombosis, which is a blood clot that develops in a vein, and

• arterial thrombosis, which is a blood clot that develops in an artery.

One of the most common types of venous thrombosis is deep vein thrombosis (DVT), which is a blood clot in one of the deep veins of the body.

Arterial thrombosis often occurs in arteries that supply the heart, resulting in a heart attack. It can also occur in the arteries of the brain, causing a stroke.

Sometimes a blood clot (or part of one) can come away from its original site and travel through the bloodstream. If this occurs, the clot can become lodged in another part of the body. This is known as an embolism. A blood clot that lodges in one of the lungs is called a pulmonary embolism.

In classical terms, thrombosis is caused by abnormalities in one or more of the following:

• The composition of the blood (hypercoagulability);

• Quality of the vessel wall (endothelial cell injury);

• Nature of the blood flow (stasis, turbulence).

The formation of a thrombus is usually caused by Virchow's triad. The pathogenesis includes an injury to the vessel's wall by trauma, infection, or turbulent flow at bifurcations; by the slowing or stagnation of blood flow past the point of injury (which may occur after long periods of sedentary behaviour, for example, sitting on a long airplane flight); by a blood state of hypercoagulability (caused, for example, by genetic deficiencies or autoimmune disorders).

Thrombosis is a widespread condition and a leading cause of death in the UK. Every year, one in every 1,000 people in the UK is affected by venous thrombosis.

Anyone can be affected by thrombosis, although it usually develops in older people and becomes more common with age. As well as age, there are a number of other factors that make developing thrombosis more likely, including family history, inactivity and obesity.

Thrombosis often has few or no symptoms, and is sometimes referred to as a silent condition. Therefore, it is important to be aware of the signs and risk factors of thrombosis. There are several things that you can do to help prevent the condition occurring.

Thrombosis and embolism can be partially prevented with anticoagulants in those deemed at risk. Generally, a risk-benefit analysis is required, as all anticoagulants lead to a small increase in the risk of major bleeding. In arterial fibrillation, for instance, the risk of stroke (calculated on the basis of additional risk factors, such as advanced age and high blood pressure) needs to outweigh the small but known risk of major bleeding associated with the use of warfarin.

Angina pectoris

Angina pectoris is the medical term for chest pain or discomfort due to coronary heart disease. Angina is a symptom of a condition called myocardial ischemia. It occurs when the heart muscle (myocardium) doesn't get as much blood as it needs. This usually happens because one or more of the heart's arteries (coronary blood vessels that supply blood to the heart muscle) is narrowed or blocked. Insufficient blood supply is called ischemia.

Angina also can occur in people with valvular heart disease, hypertrophic cardiomyopathy (this is an enlarged heart due to disease) or uncontrolled high blood pressure. These cases are rare, though. Typical angina is uncomfortable pressure, fullness, squeezing or pain in the centre of the chest. The discomfort may also be felt in the neck, jaw, shoulder, back or arm. Many types of chest discomfort aren't related to angina. Acid reflux (heartburn) and lung infection or inflammation are examples.

Angina often occurs when the heart needs more blood. For example, running to catch a bus could trigger an attack of angina while walking might not. Angina may happen during exercise, strong emotions or extreme temperatures. Some people, such as those who experience coronary artery spasm, may have angina when they are resting. Angina is a sign that someone is at increased risk of heart attack, cardiac arrest and sudden cardiac death.

People with stable angina (or chronic stable angina) have episodes of chest discomfort that are usually predictable. They occur on exertion (such as running to catch a bus) or under mental or emotional stress. Normally the chest discomfort is relieved with rest, nitroglycerin or both.

People with episodes of chest discomfort should see their physician for an evaluation. The doctor will evaluate the person's medical history and risk factors, conduct a physical exam, order a chest X-ray and take an electrocardiogram (ECG). Some people will also need an exercise ECG (stress test), an echocardiogram or other tests to complete the diagnosis.

In people with unstable angina, the chest pain is unexpected and usually occurs while at rest. The discomfort may be more severe and prolonged than typical angina or be the first time a person has angina. The most common cause is reduced blood flow to the heart muscle because the coronary arteries are narrowed by fatty buildups (atherosclerosis). An artery may be abnormally constricted or partially blocked by a blood clot. Inflammation, infection and secondary causes can also lead to unstable angina. Unstable angina is an acute coronary syndrome and should be treated as an emergency. People with new, worsening or persistent chest discomfort should be evaluated in a hospital emergency department or "chest pain unit" and monitored carefully. They are at increased risk for:

• acute myocardial infarction (heart attack);

• severe cardiac arrhythmias. These may include ventricular tachycardia and fibrillation;

• cardiac arrest leading to sudden death.

Cancer

The word cancer actually refers to many diseases, not one. In fact, there are more than 100 types of diseases known collectively as cancer. What they all have in common is the overgrowth of cells, tiny units that make up all living things. Cancer occurs when cells begin to grow and multiply in an uncontrolled way.

Normal body cells grow and divide over a period of time until they eventually die. But cancer cells continue to grow and divide and grow and divide. Eventually, they gather to form tumours. Tumours are lumps that can interfere with the body's normal processes. Sometimes cells from a tumour break away and travel to a different tissue or organ. This is called metastasis.

No one really knows why cancer grows in certain people. Scientists and researchers are working to discover why some people get cancer and others do not. This will help them to learn whether cancer can be prevented.

Doctors do have some ideas about why people may get cancer, though. The main reasons are genetics and certain environmental or behavioural triggers.

Some behavioural and environmental triggers can cause changes in the body's cells that push them into a cancerous state. For example, cigarettes are known to increase the risk of lung cancer. Too much exposure to the sun can increase the risk of skin cancer. These types of triggers act on the body slowly over time, so the cancers that may result from them don't show up until a person is an adult. Doctors do know for sure that cancer itself is not contagious, so you don't have to worry about catching it from someone else or spreading it to another person (although people with certain infectious diseases such as AIDS or hepatitis are more vulnerable to certain cancers). Cancer is also never a person's fault. It's simply not true that a person may have done something wrong to get the disease.

The first sign of cancer is a symptom - a signal that something is wrong. There are many different signs that a person may have cancer, just as there are many different forms of the disease. A few of the more common symptoms of cancer include: extreme exhaustion, swelling or lumps in certain parts of the body, such as the abdomen or neck, headaches, blurred vision, nausea, problems with walking or balance, more infections, unusual bleeding.

Only you know how your body works and what you feel like when you are healthy. If you haven't been feeling well, it's best to see a doctor who will evaluate your symptoms. Cancer, like most illnesses, is easier to treat when it's found early, so when in doubt, check it out.

If a doctor suspects that a person has cancer, he or she will order various tests. These might include blood tests, in which doctors examine blood cells under a microscope to look for problems, X-rays, a test that can be used to detect tumours. Doctors also often use a biopsy to diagnose cancer. In this procedure, a doctor removes a small tissue sample to examine it for cancer cells.

Most cancers can be treated, especially the types of cancers teens are likely to get. The number of people who beat cancer goes up every year because of new cancer treatments. There are three common methods for treating cancer: surgery, chemotherapy, and radiation.