Diseases

Pulmonary valve stenosis

Pulmonary valve stenosis is a valvular heart disease in which outflow of blood from the right ventricle of the heart is obstructed at the level of the pulmonic valve. This results in the reduction of flow of blood to the lungs. Valvular pulmonic stenosis accounts for 80% of right ventricular outflow tract obstruction.[1] While the most common cause of pulmonary valve stenosis is congenital heart disease, it may also be due to rheumatic heart disease or a malignant carcinoid tumor.[1]

Pulmonary valves agenesis

The total or partial absence of the pulmonary valve at birth. It is often associated with other malformations. Severity is variable.

Pulmonary veins stenosis

Pulmonary vein stenosis is a condition in which there is an obstruction (blockage) in the blood vessels that bring oxygen-rich blood from the lungs back to the heart. Stenosis occurs due to an abnormal process that thickens and narrows the walls in the veins. Pulmonary vein stenosis frequently progresses. As a result, total obstruction or partial loss of flow to a vessel or vessels may occur. This condition may occur as a complicating feature of complex congenital heart disease, but it may also occur in infants with otherwise normal hearts. When pulmonary vein stenosis occurs in children without congenital heart defects, it occurs in early infancy and usually progresses very rapidly. Infants with this disease may seem well for weeks before they develop difficulty breathing and low oxygen levels. They may become quite ill quickly. The effects of the disease vary in children with co-existing congenital heart defects.

Pulmonary veno-occlusive disease

Pulmonary veno-occlusive disease is an extremely rare form of high blood pressure in the lung area.

(aka Pulmonary venoocclusive disease, Venoocclusive disease of lung, Pulmonary vaso-occlusive disease)

 

Source: MedlinePlus

Pulmonary venoocclusive disease

Pulmonary venoocclusive disease is an extremely rare form of high blood pressure in the lung area.

(aka Pulmonary veno-occlusive disease, Venoocclusive disease of lung, Pulmonary vaso-occlusive disease)

 

Source: Medline Plus

Pulmonary venous return anomaly

A rare disorder where one or more of the four veins that carry oxygenated blood from the lungs drain to the right atrium of the heart instead of the left atrium. Symptom severity is determined by the number of veins involved and the exact location of the heart that the veins drain into.

Pulmonic stenosis

Pulmonic stenosis (or PS) is a general term indicating that there is obstruction to normal blood flow in the pulmonary arterial system, which conducts less oxygenated or "blue" blood to the lungs so it can become oxygenated or "pink". This can be at the level of the pulmonic valve, located between the right ventricle and the main pulmonary artery, or in the pulmonary arterial system itself . For the purposes of this discussion, we will discuss the most common type of PS, which is at the level of the valve. The pulmonic valve is normally quite thin (no more than a few millmeters in an adult), and composed of three portions arranged in a circle like a three-slice pie. Normally, the leaflets open in the direction of blood flow with each contraction of the right ventricle, then close to keep blood from traveling backward from the pulmonary arteries.

Pure red cell aplasia

Pure red cell aplasia (or PRCA) refers to a type of anemia affecting the precursors to red blood cells but not to white blood cells. In PRCA, the bone marrow ceases to produce red blood cells.

Puretic syndrome

A rare genetic condition characterized by skin tumors and enlarged gums as well as osteopenia and joint contractures. The condition is caused by the accumulation of hyaline in the skin and other tissues.

Purine nucleoside phosphorylase deficiency

A very rare genetic disease involving an enzyme (purine nucleoside phosphorylase - PNP) deficiency which causes a buildup of toxic metabolic products which in turn impairs the development of T-cells (part of the body's immune system). The condition is characterized primarily by frequent infections and various neurological symptoms.

Purpura simplex

A condition characterized by a tendency to bruise easily due to fragile blood vessels. A bruise may appear even if the person has not knowingly bumped that area. The condition is quite common but more prevalent in women than men. It is generally not considered as a serious condition as it is not associated with any other bleeding problems.

Purtilo syndrome

A rare inherited immunodeficiency disorder where the body's immune systm is unable to respond appropriately to certain viral infections (Epstein Barr virus).

Pycnodysostosis

Pycnodysostosis is perhaps best known as the diagnosis given retrospectively to the late 19th century French artist Henri de Toulouse-Lautrec (portrayed by Jose Ferrer in the 1952 film "Moulin Rouge"). Pycnodysostosis is a genetic (inherited) disease of the bone. Its pattern of inheritance follows the classic rules of genetics (see below). Pycnodysostosis consistently causes short stature. The height of adult males with the disease is less than 150 cm (59 inches, or 4 feet 1 inch). Adult females with pycnodysostosis are even shorter. Pycnodysostosis causes the bones to be abnormally dense (osteosclerosis); the last bones of the fingers (the distal phalanges) to be unusually short; and delays the normal closure of the connections (sutures)of the skull bones in infancy, so that the "soft spot" (the fontanel) on top of the head remains widely open. Pycnodysostosis causes brittle bones which easily break (fracture). The bones in the legs and feet tend to fracture. The jaw and collar bone (clavicles) are also particularly prone to fractures. The precise frequency of pycnodysostosis has never been determined. Pycnodysostosis can be classified in the large group of genetic diseases that are individually uncommon, but collectively important because of the sum of their numbers, their heavy impact upon affected individuals, and the equally heavy burden they place upon their families.

Pyknoachondrogenesis

A very rare lethal syndrome characterized mainly by abnormal skeletal growth as well as abnormal bone calcification.

Pyle disease

Pyle disease is listed as a "rare disease" by the Office of Rare Diseases (ORD) of the National Institutes of Health (NIH). This means that Pyle disease, or a subtype of Pyle disease, affects less than 200,000 people in the US population.

Pyoderma gangrenosum

Pyoderma gangrenosum is a disease that causes tissue to become necrotic, causing deep ulcers that usually occur on the legs. When they occur, they can lead to chronic wounds. Ulcers usually initially look like small bug bites or papules, and they progress to larger ulcers. Though the wounds rarely lead to death, they can cause pain and scarring. The disease was identified in 1930. It affects approximately 1 person in 100,000 in the population. Though it can affect people of any age, it mostly affects people in their 40s and 50s.[1]

Pyogenic arthritis- pyoderma gangrenosum- and acne

Pyogenic arthritis, pyoderma gangrenosum, and acne is listed as a "rare disease" by the Office of Rare Diseases (ORD) of the National Institutes of Health (NIH). This means that Pyogenic arthritis, pyoderma gangrenosum, and acne, or a subtype of Pyogenic arthritis, pyoderma gangrenosum, and acne, affects less than 200,000 people in the US population.

Pyomyositis

Pyomyositis, also known as tropical pyomyositis or myositis tropicans is a bacterial infection of the skeletal muscles which results in a pus-filled abscess. Pyomyositis is more common in tropical areas but can also occur in the temperate zones.

Pyridoxamine 5′-phosphate oxidase deficiency

The PNPO gene provides instructions for producing an enzyme called pyridoxine 5′-phosphate oxidase. This enzyme is involved in the breakdown (metabolism) of vitamin B6. Specifically, it chemically modifies two forms of vitamin B6 derived from food (pyridoxine and pyridoxamine) to form pyridoxal 5′-phosphate (PLP). PLP is the active form of vitamin B6 and is necessary for many processes in the body, including protein metabolism and the production of chemicals that transmit signals in the brain (neurotransmitters). Pyridoxine 5′-phosphate oxidase is active (expressed) in cells throughout the body, with the highest amounts found in the liver.

At least 7 mutations in the PNPO gene have been found to cause pyridoxal 5′-phosphate-dependent epilepsy. Most of these mutations change one protein building block (amino acid) in the pyridoxine 5′-phosphate oxidase enzyme, impairing its normal function. The resulting enzyme cannot effectively metabolize pyridoxine and pyridoxamine to produce PLP. A shortage of PLP can disrupt the function of many other proteins and enzymes that need PLP in order to be effective. It is not clear how the lack of PLP affects the brain and leads to the seizures that are characteristic of this condition.

Pyridoxine deficiency

Pyridoxine deficiency (also known as B6 deficiency) is a paediatric disease due to a lack of pyridoxine (or vitamin B6). The disease presents with several key symptoms including seizures, irritability, cheilitis (inflammation of the lips), conjunctivitis and neurologic symptoms. It usually becomes noticeable within the first 12 months of life in infants with a lack of pyridoxine, a coenzyme responsible for numerous essential metabolic reactions in humans. It is rarely observed, even in undeveloped countries.[1][2]

Pyridoxine-dependent epilepsy

Pyridoxine-dependent epilepsy is a condition that involves seizures beginning in infancy or, in some cases, before birth. Those affected typically experience prolonged seizures lasting several minutes (status epilepticus). These seizures involve muscle rigidity, convulsions, and loss of consciousness (tonic-clonic seizures). Additional features of pyridoxine-dependent epilepsy include low body temperature (hypothermia), poor muscle tone (dystonia) soon after birth, and irritability before a seizure episode. In rare instances, children with this condition do not have seizures until they are 1 to 3 years old. Anticonvulsant drugs, which are usually given to control seizures, are ineffective in people with pyridoxine-dependent epilepsy. Instead, people with this type of seizure are medically treated with large daily doses of pyridoxine (a type of vitamin B6 found in food). If left untreated, people with this condition can develop severe brain dysfunction (encephalopathy). Even though seizures can be controlled with pyridoxine, neurological problems such as developmental delay and learning disorders may still occur.

Pyrimidinemia familial

A metabolic error where a deficiency of an enzyme called dihydropyrimidine dehydrogenase prevents the normal metabolism of certain proteins. High levels of certain proteins are excreted in the urine. The enzyme is also needed the breakdown a chemotherapy drug called 5-flurouracil and its absence can result in a severe toxicity reaction.

Pyropoikilocytosis

A rare inherited condition where abnormal red blood cells are very sensitive to heat resulting in their destruction and hence, hemolytic anemia.

Pyrosis

Pyrosis: The occurrence of chest pain which is consistent with gastro-oesophageal reflux. See free access online books about Pyrosis below. See detailed information below for a list of 0 causes of Pyrosis, including diseases and drug side effect causes.

Pyruvate carboxylase deficiency

Pyruvate carboxylase deficiency (PCD) is a rare non-sex linked (autosomal) disorder that results from an insufficient amount of the enzyme pyruvate carboxylase. This disorder is inherited as a recessive trait and it is known to be caused by more than one different mutation in the same gene (allelic variants).

Pyruvate decarboxylase deficiency

A rare genetic disorder involving an enzyme (pyruvate decarboxylase) deficiency which results in symptoms such as failure to thrive, psychomotor retardation, small head, eye problems, increased blood ammonia levels and lactic acidosis which can result in infant death in severe cases.

Pyruvate Dehydrogenase Complex Deficiency

Pyruvate dehydrogenase complex deficiency (PDCD) is a rare disorder of carbohydrate metabolism caused by a deficiency of one of the three enzymes in the pyruvate dehydrogenase complex (PDC). The age of onset and severity of disease symptoms vary widely. Individuals with PDCD symptom onset in the prenatal period or in infancy usually die in early childhood. Those who develop PDCD later in childhood may have neurological symptoms but usually survive into adulthood. Most individuals with PDCD have an abnormality in the PDHA1 gene located on the X chromosome. A smaller percentage of affected individuals have forms of the disorder that follow autosomal recessive inheritance.