Achalasia is a rare disease of the muscle of the esophagus (swallowing tube). The term achalasia means "failure to relax" and refers to the inability of the lower esophageal sphincter (a ring of muscle situated between the lower esophagus and the ...

Understanding the key reason of adult-onset asthma and identifying unique phenotypes may hel...

Primary aldosteronism (al-DOS-tuh-ro-niz-um) is a type of hormonal disorder that leads to high blood pressure. Your adrenal glands produce a number of essential hormones. One of these is aldosterone, which balances sodium and potassium in your blo...

What is angina? The heart is the pump responsible for circulating blood throughout the body. Myocardium (myo=muscle + cardium=muscle) is the heart muscle that contracts to pump that blood and like any other muscle, it requires oxygen rich ...

The heart is the pump responsible for circulating blood throughout the body. Myocardium (myo=muscle + cardium=muscle) is the heart muscle that contracts to pump that blood and like any other muscle, it requires oxygen rich blood for energy. Angina...

Introduction to aortic dissection The aorta is the large blood vessel that leads from the heart and carries blood to the rest of the body. It originates at the aortic valve at the outlet of the left ventricle of the heart and ascends withi...

What is aortic stenosis? Aortic stenosis is abnormal narrowing of the aortic valve. A number of conditions cause disease resulting in narrowing of the aortic valve. When the degree of narrowing becomes significant enough to impede the flow...

Aortic stenosis is abnormal narrowing of the aortic valve. A number of conditions cause disease resulting in narrowing of the aortic valve. When the degree of narrowing becomes significant enough to impede the flow of blood from the left ventricle...

A heart arrhythmia (uh-RITH-me-uh) is an irregular heartbeat. Heart rhythm probl...

A heart arrhythmia (uh-RITH-me-uh) is an irregular heartbeat. Heart rhythm problems (heart arrhythmias) occur when the electrical signals that coordinate the heart's beats don't work properly. The faulty signalling causes the heart to beat too fas...

What is the definition of asbestos? Asbestos is a family of naturally occurring silica compounds (similar to, but not the same as, the silica of window glass and computer chips). These substances form fibers with varying shapes and sizes a...

A disorder in which a person's airways become inflamed, constrict, and bulge, as well as cre...

In childhood asthma, the lungs and airways become easily inflamed when exposed to certain triggers, such as inhaling pollen or catching a cold or other respiratory infection. Childhood asthma can cause bothersome daily symptoms t...

Atopic dermatitis facts Atopic dermatitis is a type of eczema. The disease may be inherited and genetically determined. The patient's skin may be "super sensitive" to many irritants. Dry, scaly patches ...

Atrial fibrillation (A-fib) is an irregular and often very rapid heart rhythm (a...

Atrial fibrillation (A-fib) is an irregular and often very rapid heart rhythm (arrhythmia) that can lead to blood clots in the heart. A-fib increases the risk of stroke, heart failure and other he...

Jervell and Lange-Nielsen syndrome (JLNS) is a rare inherited disorder characterized by deafness present at birth (congenital) occurring in association with abnormalities affecting the electrical system of the heart. The severity of cardiac sympto...

Bronchitis is an infection that causes irritation and inflammation in the lungs' major airways (bronchi). Bronchitis is divided into two types: acute and chronic. Chronic bronchitis is a long-term condition that can reoccur. Long-term stress, such...

Bronchitis is an infection that affects the lungs' major airways (bronchi), causing irritation and inflammation. Bronchitis can be classified into two types: acute and long-term. Chronic bronchitis is a long-term problem that can come back. It is usu...

Carcinoid syndrome is a disease consisting of a combination of symptoms, physical manifestations, and abnormal laboratory findings. Carcinoid syndrome is seen in individuals who have an underlying carcinoid tumour with spread to the liver. Carcino...

Hajdu-Cheney syndrome (HCS) is a rare, heritable disorder of connective tissue; only about 50 cases have been reported in the medical literature. The breakdown of bone (osteolysis), especially the outermost bones of the fingers and toes (acroosteo...

Chronic Bronchitis is a type of COPD (chronic obstructive pulmonary disease). COPD is a lung infection and disease that can make breathing difficult and progressively worsen over time. Other than COPD, the most common type of COPD is emphysema. Th...

The inflammation of the joints that connect the ribs to the breast bone is known as costochondritis. Costochondritis can develop as a result of genetics, viruses, or even an accident. Costochondritis can be a separate medical condition or a sympto...

Adenoid cystic carcinoma (ACC) is a relatively rare form of cancer that most commonly develops in the salivary glands or other regions of the head and neck. In some cases, ACC may arise in other primary sites, such as the skin; the breast; the nec...

An interstitial lung disease occurs when there is cryptogenic fibrous alveolitis in the lungs (or ILD for short). They have an impact on the tissues that support the air sacs in the lungs, making it difficult for them to take in as much air as the...

General DiscussionThe word "neurasthenia" is a term that has fallen into disuse among psychiatrists in the United States and Australia. It remains in use in the United Kingdom. Where it is used, it covers a wide spectrum of symptoms inclu...

General DiscussionJervell and Lange-Nielsen syndrome (JLNS) is a rare inherited disorder characterized by deafness present at birth (congenital) occurring in association with abnormalities affecting the electrical system of the heart. The...

Dyggve-Melchior-Clausen (DMC) syndrome is a rare, progressive genetic disorder characterized by abnormal skeletal development, microcephaly and intellectual disability. The condition was first reported by Dyggve, Melchior and Clausen in 1962 in th...

Dyggve-Melchior-Clausen (DMC) syndrome is a rare, progressive genetic disorder characterized by abnormal skeletal development, microcephaly and intellectual disability. The condition was first reported by Dyggve, Melchior and Clausen in 1962 in th...

Emery-Dreifuss muscular dystrophy (EDMD) is a rare, often slowly progressive genetic disorder affecting the muscles of the arms, legs, face, neck, spine and heart. The disorder consists of the clinical triad of weakness and degeneration (atrophy) ...

Emphysema is a lung disease that usually develops after a long period of smoking. Chronic bronchitis and emphysema are both types of lung disorders that are classified as chronic obstructive pulmonary disease (COPD) (COPD). COPD is an umbrella ter...

Atrioventricular septal defect (ASVD) is a general term for a group of rare heart defects that are present at birth (congenital). Infants with ASVDs have improperly developed atrial and ventricular septa and adjoining valves. The norma...

Endocardial fibroelastosis (EFE) is a rare heart disorder that affects infants and children. It is characterized by a thickening within the muscular lining of the heart chambers due to an increase in the amount of supporting connective tissue (ine...

Erythema nodosum is a type of skin inflammation that is located in a certain portion of the fatty layer of skin. Erythema nodosum (also called EN) results in reddish, painful, tender lumps most commonly located in the front of the legs below the k...

Achalasia is a rare disorder of the esophagus, the tube that carries food from the throat to the stomach. It is characterized by enlargement of the esophagus, impaired ability to push food down toward the stomach (peristalsis), and failure of the ...

What is the esophagus? The esophagus is a muscular tube in the chest. It's about 10 inches (25 centimeters) long. This organ is part of the digestive tract. Food moves from the mouth through the esophagus to the stomach. Th...

Cryptococcosis is caused by a fungus known as Cryptococcosis neoformans. The infection may be spread to humans through contact with pigeon droppings or unwashed raw fruit. Contact with an infected individual may also spread the infection. Individu...

Extrinsic Allergic Pneumonia, also known as Allergic Interstitial Pneumonitis and Hypersensitivity Pneumonitis, is an inflammatory syndrome that affects the lungs. Extrinsic: the origin is an external matter - an antigen. Allergic: The cau...

Pediatric cardiomyopathy is a rare heart condition that affects infants and children. Specifically, cardiomyopathy means disease of the heart muscle (myocardium). Several different types of cardiomyopathy exist and the specific symptoms vary from ...

Fibrosing Alveolitis, also known as Pulmonary Fibrosis, is a lung condition that affects the tissues that support the air sacs. As a result, it is more difficult for them to absorb the necessary oxygen for respiration. The lung tissues thicken and...

General DiscussionWeil syndrome, a rare infectious disorder, is a severe form of the bacterial infection caused by Leptospira bacteria known as leptospirosis. Weil syndrome is characterized by dysfunction of the kidneys and liver, abnorma...

The word "neurasthenia" is a term that has fallen into disuse among psychiatrists in the United States and Australia. It remains in use in the United Kingdom. Where it is used, it covers a wide spectrum of symptoms including the sensation of pain ...

Mallory-Weiss syndrome refers to a tear or laceration of the mucous membrane, most commonly at the point where the esophagus and the stomach meet (gastroesophageal junction). Such a tear may result in severe bleeding from the gastrointestinal trac...

Giant cell myocarditis is a rare cardiovascular disorder that occurs for unknown reasons (idiopathic). It is characterized by inflammation of the heart muscle (myocardium), a condition referred to as myocarditis. Inflammation is caused by widespre...

Progeria, or Hutchinson-Gilford progeria syndrome (HGPS), is a rare, fatal, genetic condition of childhood with striking features resembling premature aging. Children with progeria usually have a normal appearance in early infancy. At approximatel...

Grover's disease is a rare, transient skin disorder that consists of small, firm, raised red lesions, most often on the skin of the chest and back. Diagnosis of this disorder becomes apparent under microscopic examination when the loss of the "cem...

A heart attack occurs when the flow of blood to the heart is severely reduced or...

Cardiac catheterization (also called cardiac cath or coronary angiogram) is an invasive imaging procedure that tests for heart disease by allowing your doctor to see how well your heart is functioning. During the test, a long, narrow tube, called ...

Cardiac catheterization (also called cardiac cath or coronary angiogram) is an invasive imaging procedure that tests for heart disease by allowing your doctor to see how well your heart is functioning. During the test, a long, narrow tube, called ...

Heart disease is the leading cause of death among women. An estimated 90% of women have at least one risk factor for heart disease. Heart attack symptoms can be different for women than for men. Younger women wit...

Heart disease is the leading cause of death among women. An estimated 90% of women have at least one risk factor for heart disease. Heart attack symptoms can be different for women than for men. Younger women wit...

According to the American Heart Association, about 5 million Americans are diagnosed with valvular heart disease each year. What Is Valvular Heart Disease? Heart valve disease occurs when your heart's valves do not work the way the...

Introduction to heart transplant The idea of replacing a bad organ with a good one has been documented in ancient mythology. The first real organ transplants were probably skin grafts that may have been done in India as early as the second...

Heat rash facts Heat rash occurs when the skin's sweat glands are blocked and the sweat produced cannot get to the surface of the skin to evaporate. This causes inflammation that results in a rash. Common symptoms of heat ...

Histoplasmosis is an infection caused by the fungus Histoplasma. The fungus can be found in the environment, particularly in soil with a high concentration of bird or bat droppings. Histoplasma is mostly found in the central and eastern United Sta...

Bartter's syndrome (BS) is a group of conditions involving enlargement of certain kidney cells, blood that is more alkaline than normal, high levels of potassium and chloride in the urine, loss of potassium from the kidneys (renal potassium wastin...

Hypophosphatasia is a inborn metabolic disorder of the bones characterized by skeletal defects resembling those of rickets. The symptoms result from a failure of bone mineral to be deposited in young, uncalcified bone (osteoid), and in the cartila...

General DiscussionPediatric cardiomyopathy is a rare heart condition that affects infants and children. Specifically, cardiomyopathy means disease of the heart muscle (myocardium). Several different types of cardiomyopathy exist and the s...

General DiscussionGiant cell myocarditis is a rare cardiovascular disorder that occurs for unknown reasons (idiopathic). It is characterized by inflammation of the heart muscle (myocardium), a condition referred to as myocarditis. Inflamm...

A keloid scar forms from abnormal healing, and usually develops in people 10 to 20 years old. A keloid, or keloid scar, is a kind of overgrown scar, or an overly aggressive healing response to a wound. It's a type of thick, irregul...

Seborrheic Keratosis is a skin disorder usually characterized by discolored lesions that appear to be "stuck on" the skin surface. Warts may appear and skin is often oily or greasy. These skin lesions are sometimes mistaken for cancerous growths a...

Congenital lobar emphysema is a rare respiratory disorder in which air can enter the lungs but cannot escape, causing overinflation (hyperinflation) of the lobes of the lung. It is most often detected in newborns or young infants, but some cases d...

Congenital lobar emphysema is a rare respiratory disorder in which air can enter the lungs but cannot escape, causing overinflation (hyperinflation) of the lobes of the lung. It is most often detected in newborns or young infants, but some cases d...

General DiscussionEndomyocardial fibrosis (EMF) is a progressive disease of unknown origin (idiopathic) that may seriously affect the heart. Its most obvious feature is a gross change in the makeup of the lining of the heart cavities (the...

Lung cancer facts Lung cancer is the number one cause of cancer deaths in both men and women in the U.S. and worldwide. Cigarette smoking is the principal risk factor for development of lung cancer. Passive exposure to tobac...

Lung cancer facts Lung cancer is the number one cause of cancer deaths in both men and women in the U.S. and worldwide. Cigarette smoking is the principal risk factor for development of lung cancer. Passive exposure to tobac...

Systemic lupus erythematosus (SLE) is an autoimmune disease. SLE is characterized by the production of unusual antibodies in the blood. SLE is eight times more common in women than men. The cause(s) of SLE is (ar...

Lymphangioleiomyomatosis (LAM) is a condition that occurs due to abnormal growth of smooth muscle cells, especially in the lymphatic systems and the lungs. This growth leads to the formation of cysts or holes in the lungs.  Peo...

Noonan syndrome is a common genetic disorder that is typically evident at birth (congenital). The disorder is characterized by a wide spectrum of symptoms and physical features that vary greatly in range and severity. In many affected individuals,...

Mesothelioma is a rare form of cancer that affects the membrane that covers and protects various internal organs of the body (mesothelium). The mesothelium is composed of two layers of specialized cells known as mesothelial cells. One layer direct...

Mallory-Weiss syndrome refers to a tear or laceration of the mucous membrane, most commonly at the point where the esophagus and the stomach meet (gastroesophageal junction). Such a tear may result in severe bleeding from the gastrointestinal trac...

Mallory-Weiss syndrome refers to a tear or laceration of the mucous membrane, most commonly at the point where the esophagus and the stomach meet (gastroesophageal junction). Such a tear may result in severe bleeding from the gastrointestinal trac...

Mesothelioma is a rare form of cancer (malignancy) that most frequently arises from the cells lining the sacs of the chest (the pleura) or the abdomen (the peritoneum). Pleural mesothelioma is the most common form, often presenting with symptoms i...

What is mitral valve prolapse? Mitral valve prolapse (also known as "click murmur syndrome" and "Barlow's syndrome") is the most common heart valve abnormality. The condition is slightly more prevalent in women than in men. The mitral valv...

Moebius syndrome is a rare neurological disorder characterized by weakness or paralysis (palsy) of multiple cranial nerves, most often the 6th (abducens) and 7th (facial) nerves. Other cranial nerves are sometimes affected. The disorder is present...

Munchausen syndrome is a mental disorder that is characterized by the sufferer causing or pretending to have physical or psychological symptoms in his or herself. Adults aged 20-40 years are the most likely groups to develop Munchau...

General DiscussionNeonatal lupus is a rare autoimmune disorder that is present at birth (congenital). Affected infants often develop a characteristic red rash or skin eruption. In addition, infants with neonatal lupus may develop liver di...

Nocardiosis is an infectious pulmonary disease characterized by abscesses in the lungs. These abscesses may extend through the chest wall. The infection is spread through the body via the bloodstream by a microorganism called Nocardia asteroids....

General DiscussionPediatric cardiomyopathy is a rare heart condition that affects infants and children. Specifically, cardiomyopathy means disease of the heart muscle (myocardium). Several different types of cardiomyopathy exist and the s...

Hypertrophic cardiomyopathy (HCM) is a disease in which the heart muscle becomes...

What is pericarditis? The heart muscle has a tight covering that surrounds it, a lining sac called the pericardium (peri=around +cardium=heart). This sac actually has two layers. The visceral pericardium is only one cell layer thick and fi...

Pityriasis rosea facts Pityriasis rosea begins as a single, large pink patch found on the trunk called the "herald patch." The herald patch is followed one to two weeks later with smaller pink patches in a "Christmas tree"...

Pleurisy (pleuritis) is a health condition that occurs when the pleura, the thin layer of tissue that covers the lungs, becomes inflamed. Pleurisy (pleuritis) can be caused by a variety of things, including viruses, bacteria, and even lung cancer....

Pneumonia is an inflammatory infection that develops in the lungs. This disease fills up air sacs with fluid or pus that leads to cough with phlegm, fever, and difficulty in breathing. We inhale air from the nose or mouth that reach...

Pneumonia is a lung infection that can be caused by bacteria, viruses, or fungi. It causes inflammation in the air sacs in the lungs, leading to symptoms such as cough, fever, difficulty breathing, and chest pain. Pneumonia can range from mild to ...

Pneumothorax (collapsed lung) is a medical condition in which either the lungs collapse on the whole or only a portion of the lungs collapse. In this condition, the air enters the area between the lungs and chest wall known as a plural stag. ...

Pneumothorax (collapsed lung) is a medical condition in which either the lungs collapse on the whole or only a portion of the lungs collapse. In this condition, the air enters the area between the lungs and chest wall known as a plural stag. ...

Polycystic ovary syndrome  Polycystic ovary syndrome is a disorder involving infrequent, irregular or prolonged menstrual periods, and often excess male hormone (androgen) levels. The ovaries develop numerous small collections of flui...

Preeclampsia is a pregnancy complication characterized by high blood pressure and signs of damage to another organ system, most often the liver and kidneys. Preeclampsia usually begins after 20 weeks of pregnancy in women whose blood pressure had ...

General DiscussionWolff-Parkinson-White (WPW) syndrome is a rare congenital heart disorder involving irregularities in the electrical system of the heart. In individuals with WPW syndrome, an abnormal alternate electrical pathway (accesso...

Pernicious anemia is a rare blood disorder characterized by the inability of the body to properly utilize vitamin B12, which is essential for the development of red blood cells. Most cases result from the lack of the gastric protein known as intri...

Pulmonary alveolar proteinosis is a lung disorder characterized by a build-up of proteins, lipids, and other substances (together known as surfactants) in the lungs' air sacs, or alveoli. The alveoli are the air-holding cells in the lungs. The exc...

Pulmonary angiitis is a term used to describe a collection of disorders with both a vascular (angiitis) and granulomatous components. It means inflammation of blood vessels in the lungs.  There are five unique clinical syndromes that ...

Pulmonary hypertension is a life-threatening illness if not taken care of properly. If diagnosed, treatments can alleviate the symptoms and help you live with the disease more comfortably. High blood pressure in the arteries that run from your hea...

General DiscussionSecondary pulmonary hypertension is a disorder of the blood vessels in the lungs. It usually is the result of other lung diseases or related diseases in other organs. Affected individuals have high blood pressure (hypert...

Lymphomatoid granulomatosis is a rare disorder characterized by overproduction (proliferation) of white blood cells called lymphocytes (lymphoproliferative disorder). The abnormal cells infiltrate and accumulate (form lesions or nodules) within ti...

Pump lung, (also known as Shock Lung), is inflammatory lung damage.  Pump lung is caused by fluid buildup in the lungs' small air sacs (called alveoli), which makes breathing very difficult. It also results in severely low bloo...

Why does reflux laryngitis occur? Reflux is caused by weakness in the muscle at the junction of the esophagus with the stomach. Normally, this muscular valve, or sphincter, functions to keep food and stomach acid from moving upward from th...

General DiscussionRomano-Ward syndrome is an inherited heart (cardiac) disorder characterized by abnormalities affecting the electrical system of the heart. The severity of Romano-Ward syndrome varies greatly from case to case. Some indiv...

Androgen insensitivity refers to an inability of the body to respond properly to male sex hormones (androgens) produced during pregnancy. This occurs because of a change (mutation) in a gene involved in the production of the protein inside cells t...

Androgen insensitivity refers to an inability of the body to respond properly to male sex hormones (androgens) produced during pregnancy. This occurs because of a change (mutation) in a gene involved in the production of the protein inside cells t...

The sarcoid of boeck (sarcoidosis) is a chronic inflammatory disease that can affect any organ in the body, but most often involves the skin and lungs.  Sarcoid of boeck is characterized by the formation of small, round bumps (...

SHORT syndrome is a condition in which affected individuals have multiple birth defects in different organ systems. The term SHORT is an acronym with each letter representing one of the common findings in affected persons:(S)= short st...

Dyggve-Melchior-Clausen (DMC) syndrome is a rare, progressive genetic disorder characterized by abnormal skeletal development, microcephaly and intellectual disability. The condition was first reported by Dyggve, Melchior and Clausen in 1962 in th...

Stomach cancer is an abnormal growth of cells that begins in the stomach. The st...

General DiscussionEndocardial fibroelastosis (EFE) is a rare heart disorder that affects infants and children. It is characterized by a thickening within the muscular lining of the heart chambers due to an increase in the amount of suppor...

Large arteries Open pop-up dialog box Close Large arteries Large arteries Takayasu's arteritis is a form of vasculitis — inflammation of the blood vessels — that damages the large arteries, especially the aorta. Chamber...

Vascular disease includes any condition that affects the circulatory system. As the heart beats, it pumps blood through a system of blood vessels called the circulatory system. The vessels are elastic tubes that carry blood to every part of the bo...

Vascular disease includes any condition that affects the circulatory system. As the heart beats, it pumps blood through a system of blood vessels called the circulatory system. The vessels are elastic tubes that carry blood to every part of the bo...

Tinea versicolor is a common fungal infection of the skin. The fungus interferes with the normal pigmentation of the skin, resulting in small, discolored patches. These patches may be lighter or darker in color than the surrounding skin and most c...

Torulosis is an airborne disease. It is more famously referred to as cryptococcosis. When you inhale infected dust, torulosis slowly spreads throughout your lungs, presenting as pneumonia. It could potentially be fatal. Sometimes, i...

Grover's disease is a rare, transient skin disorder that consists of small, firm, raised red lesions, most often on the skin of the chest and back. Diagnosis of this disorder becomes apparent under microscopic examination when the loss of the "cem...

Tuberculosis (TB) is a potentially serious infectious disease that mainly affect...

Tuberculosis (TB) is a contagious bacterial infection that primarily affects the lungs, but can also affect other parts of the body such as the kidneys, spine, and brain. It is caused by the bacterium Mycobacterium tuberculosis and is spread throu...

Usual Interstitial Pneumonia (UIP) is a radiologic and histopathologic pattern of interstitial lung disease.  The prognosis of usual interstitial pneumonia (UIP) is poor as the current therapies related to it are of unproven va...

What is a ventricular septal defect (VSD)? A ventricular septal defect (VSD) is a heart malformation present at birth. Any condition that is present at birth can also be termed a "congenital" condition. A VSD, therefore, is a type of conge...

What is a ventricular septal defect (VSD)? A ventricular septal defect (VSD) is a heart malformation present at birth. Any condition that is present at birth can also be termed a "congenital" condition. A VSD, therefore, is a type of conge...

General DiscussionVentricular septal defects are heart defects that are present at birth (congenital). The normal heart has four chambers. The two upper chambers, known as atria, are separated from each other by a fibrous partition known ...

General DiscussionRomano-Ward syndrome is an inherited heart (cardiac) disorder characterized by abnormalities affecting the electrical system of the heart. The severity of Romano-Ward syndrome varies greatly from case to case. Some indiv...

Keratosis follicularis, also known as Darier disease, is a rare, genetic skin disorder. Affected individuals develop skin lesions that consist of thickened, rough bumps (papules) or plaques that may also be greasy or have a brown or yellow crust. ...

General DiscussionWolff-Parkinson-White (WPW) syndrome is a rare congenital heart disorder involving irregularities in the electrical system of the heart. In individuals with WPW syndrome, an abnormal alternate electrical pathway (accesso...

Takayasu arteritis is a rare disorder characterized by the progressive inflammation of one or more of the larger arteries leading from the heart. The main artery of the heart (aorta) and the pulmonary (lung) artery, among others, may be affected. ...