One or both of the leaflets (cusps) of the mitral valve bulges back into the left atrium upon contraction of the left ventricle.

Failure of the tricuspid valve to close sufficiently upon contraction of the right ventricle, causing blood to regurgitate (flow backward) into the right atrium.

Increase in size of the right atrium.

Pulmonary hypertension is defined mean pulmonary artery pressure of 25mmHg or more and pulmonary capillary wedge pressure of 15mmHg or less when measured by right heart catheterisation at rest and in a supine position.

Failure to thrive (FTT) refers to a child whose physical growth is substantially below the norm.

Distention of the abdomen.

Impairment of bile flow due to obstruction in bile ducts.

Abnormally increased size of the liver.

Forceful ejection of the contents of the stomach through the mouth by means of a series of involuntary spasmic contractions.

The presence of chronic diarrhea, which is usually taken to mean diarrhea that has persisted for over 4 weeks.

A condition in which the stomach contents leak backwards from the stomach into the esophagus through the lower esophageal sphincter.

Loss of strength in the arm, leg, and sometimes face on one side of the body. Hemiplegia refers to a complete loss of strength, whereas hemiparesis refers to an incomplete loss of strength.

A state of disinterest, listlessness, and indifference, resulting in difficulty performing simple tasks or concentrating.

A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age.

A type of Developmental delay characterized by a delay in acquiring motor skills.

Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist.

Collapse of part of a lung associated with absence of inflation (air) of that part.

Persistent abnormal dilatation of the bronchi owing to localized and irreversible destruction and widening of the large airways.

A sudden, audible expulsion of air from the lungs through a partially closed glottis, preceded by inhalation.

A persistent cough, defined as a cough lasting longer than eight weeks in adults or longer than four weeks in children.

Difficult or labored breathing. Dyspnea is a subjective feeling only the patient can rate, e.g., on a Borg scale.

The presence of an excessive amount of fluid in the pleural cavity.

Crackles are discontinuous, explosive, and nonmusical adventitious lung sounds normally heard in inspiration and sometimes during expiration. Crackles are usually classified as fine and coarse crackles based on their duration, loudness, pitch, timing in the respiratory cycle, and relationship to coughing and changing body position.

A high-pitched whistling sound associated with labored breathing.

Perceived difficulty to breathe that occurs with exercise or exertion and improves with rest.

An increased susceptibility to lower respiratory tract infections as manifested by a history of recurrent lower respiratory tract infections.

Radiological appearance of increased density around the walls of a bronchus or large bronchiole. This feature is thought to be related to edema involving the bronchial wall as well as the peribronchial interstitial space. If the cross section of a bronchus is captured in a radiograph or computed tomography image, it is said to have the appearance of a donut because of the central lucency representing the airway of the bronchus surrounded by a circular region of increased density.

Abnormality of the lung parenchyma extending to the pulmonary interstitium and leading to diffuse pulmonary fibrosis.

On chest radiographs, ground-glass opacity appears as an area of hazy increased lung opacity, usually extensive, within which margins of pulmonary vessels may be indistinct. On CT scans, it appears as hazy increased opacity of lung, with preservation of bronchial and vascular margins. It is caused by partial filling of airspaces, interstitial thickening (due to fluid, cells, and/or fibrosis), partial collapse of alveoli, increased capillary blood volume, or a combination of these, the common factor being the partial displacement of air. Ground-glass opacity is less opaque than consolidation, in which bronchovascular margins are obscured.

Asthma is characterized by increased responsiveness of the tracheobronchial tree to multiple stimuli, leading to narrowing of the air passages with resultant dyspnea, cough, and wheezing.

An abnormal increase in the number of leukocytes in the blood.

Hilar lymphadenopathy is swelling or enlargement of lymph nodes localized in hila, wedge-shaped anatomical structures containing pulmonary vessels, major bronchi, nerves and lymph nodes. Hilar lymph nodes are not visible on chest X-ray if they are not enlarged. Hilar lymph node enlargement can be caused by benign and malignant conditions and can be symmetrical (bilateral) or asymmetrical (unilateral).

Increased susceptibility to otitis media, as manifested by recurrent episodes of otitis media.

An increased concentration of chloride in the sweat.

The palpebral fissure inclination is more than two standard deviations above the mean for age (objective); or, the inclination of the palpebral fissure is greater than typical for age.

Forward prominence of the entire forehead, due to protrusion of the frontal bone.

Height of the vermilion of the upper lip in the midline more than 2 SD below the mean. Alternatively, an apparently reduced height of the vermilion of the upper lip in the frontal view (subjective).

Swelling of lymph nodes within the mediastinum, the central compartment of the thoracic cavities that contains the heart and the great vessels, the esophagus, and trachea and other structures including lymph nodes.