Abnormally late or absent menarche in a female with normal secondary sexual characteristics.

A hole between the two bottom chambers (ventricles) of the heart. The defect is centered around the most superior aspect of the ventricular septum.

A deficiency or slowing down of growth pre- and postnatally.

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

Feeding problem necessitating food and nutrient delivery via a tube.

Abnormally increased size of the liver.

A chronic disorder of the liver in which liver tissue becomes scarred and is partially replaced by regenerative nodules and fibrotic tissue resulting in loss of liver function.

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

Impaired function of the exocrine pancreas associated with a reduced ability to digest foods because of lack of digestive enzymes.

A form of hepatic steatosis characterized by the presence of small, lipid-laden vesicles in the affected hepatocytes.

Neonatal jaundice refers to a yellowing of the skin and other tissues of a newborn infant as a result of increased concentrations of bilirubin in the blood. Neonatal jaundice affects over half of all newborns to some extent in the first week of life. Prolonged neonatal jaundice is said to be present if the jaundice persists for longer than 14 days in term infants and 21 days in preterm infants.

A type of cirrhosis characterized by the presence of large regenerative nodules.

Steatosis is a term used to denote lipid accumulation within hepatocytes.

A bilateral form of sensorineural hearing impairment.

A profound (essentially complete) form of hearing impairment.

The corpus callosum is the largest fiber tract in the central nervous system and the major interhemispheric fiber bundle in the brain. Formation of the corpus callosum begins as early as 6 weeks' gestation, with the first fibers crossing the midline at 11 to 12 weeks' gestation, and completion of the basic shape by age 18 to 20 weeks (Schell-Apacik et al., 2008). Agenesis of the corpus callosum (ACC) is one of the most frequent malformations in brain with a reported incidence ranging between 0.5 and 70 in 10,000 births. ACC is a clinically and genetically heterogeneous condition, which can be observed either as an isolated condition or as a manifestation in the context of a congenital syndrome (see MOLECULAR GENETICS and Dobyns, 1996). Also see mirror movements-1 and/or agenesis of the corpus callosum (MRMV1; 157600). Schell-Apacik et al. (2008) noted that there is confusion in the literature regarding radiologic terminology concerning partial absence of the corpus callosum, where various designations have been used, including hypogenesis, hypoplasia, partial agenesis, or dysgenesis.

A generalized-onset seizure is a type of seizure originating at some point within, and rapidly engaging, bilaterally distributed networks. The networks may include cortical and subcortical structures but not necessarily the entire cortex.

Underdevelopment of the corpus callosum.

A delay in the acquisition of the ability to use language to communicate needs, wishes, or thoughts.

A type of motor delay characterized by a delay in acquiring the ability to control the large muscles of the body for walking, running, sitting, and crawling.

An increase in size of the ventricular system of the brain.

A reduction in erythrocytes volume or hemoglobin concentration.

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.

Reduced strength of one or more muscles innervated by the facial nerve (the seventh cranial nerve).

A form of developmental hypoplasia of the mandible in which the mandible is mislocalised posteriorly.

The capability that a joint (or a group of joints) has to move, passively and/or actively, beyond normal limits along physiological axes.

Head circumference below 2 standard deviations below the mean for age and gender.

Polycystic lung disease (PCLUD) is an autosomal recessive disorder characterized by childhood-onset exertional dyspnea and cough due to progressive airflow obstruction in the lungs. Pulmonary imaging shows diffuse lung disease with pleural and subpleural cysts and peripheral consolidations, and lung biopsy shows bronchiolitis and lymphocytosis of the terminal bronchioles, often with features of pulmonary alveolar proteinosis (PAP). Most affected individuals have recurrent respiratory infections; some have an adverse response to BCG vaccination. Additional features may include digital clubbing, allergies, and atopic dermatitis (et al., 2024).

Systemic inflammatory response to infection.

Abnormal increased size of the spleen.

An accessory spleen is a round, iso-echogenic, homogenic and smooth structure and is seen as a normal variant mostly on the medial contour of the spleen, near the hilus or around the lower pole. This has no pathogenic relevance.

Enlargement (swelling) of a lymph node.

Polysplenia is a congenital disease manifested by multiple small accessory spleens.

A decreased concentration of glucose in the blood.

Blood glucose concentration below the lower limit of established reference ranges in a newborn.

An abnormal increase in the level of triglycerides in the blood.

Abnormally increased level of blood lactate (2-hydroxypropanoic acid). Lactate is produced from pyruvate by lactate dehydrogenase during normal metabolism. The terms lactate and lactic acid are often used interchangeably but lactate (the component measured in blood) is strictly a weak base whereas lactic acid is the corresponding acid. Lactic acidosis is often used clinically to describe elevated lactate but should be reserved for cases where there is a corresponding acidosis (pH below 7.35).

Height of the palate more than 2 SD above the mean (objective) or palatal height at the level of the first permanent molar more than twice the height of the teeth (subjective).

Epicanthus is a condition in which a fold of skin stretches from the upper to the lower eyelid, partially covering the inner canthus. Usher (1935) noted that epicanthus is a normal finding in the fetus of all races. Epicanthus also occurs in association with hereditary ptosis (110100).

Posterior positioning of the nasal root in relation to the overall facial profile for age.

Increased breadth of the nasal bridge (and with it, the nasal root).

Increased prominence or roundness of soft tissues between zygomata and mandible.

Elevated ridge(s) of skin starting well below the medial aspect of the lower lid that curves gradually upward toward and/or across the nasal bridge.

The birth of a baby of less than 37 weeks of gestational age.

Inability to see well at night or in poor light.

Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms.

An absolute or relative decrease in retinal sensitivity extending from edge (periphery) of the visual field in a concentric pattern. The visual field is the area that is perceived simultaneously by a fixating eye.

An eye that is more deeply recessed into the plane of the face than is typical.

Well-demarcated area(s) of partial or complete depigmentation in the macula, reflecting atrophy of the retinal pigment epithelium with associated retinal photoreceptor loss.