Pediatrics Glossary

Proactive counseling provided to parents during well-child visits about expected developmental changes, safety precautions, nutrition, and behavioral issues appropriate for the child's upcoming developmental stage.

A scoring system (0-10) used to rapidly assess a newborn's condition at 1 and 5 minutes after birth based on Appearance, Pulse, Grimace, Activity, and Respiration.

An acute lower respiratory tract infection primarily caused by RSV, affecting infants and young children, characterized by wheezing, tachypnea, and respiratory distress.

A growth chart showing the distribution of a measurement (weight, height, head circumference) across a reference population, used to track a child's growth trajectory over time.

A structural or functional abnormality present at birth resulting from errors in embryonic or fetal development, including conditions such as congenital heart defects, neural tube defects, and cleft palate.

Laryngotracheobronchitis, a viral infection (usually parainfluenza) causing subglottic airway swelling that produces a characteristic barking cough, stridor, and hoarseness in young children.

A deficit of total body water caused by decreased intake or increased losses (vomiting, diarrhea, fever). In children, it is classified as mild (3-5%), moderate (6-9%), or severe (>10%) based on percentage of body weight lost.

A significant lag in one or more domains of development (gross motor, fine motor, speech/language, cognitive, social-emotional) relative to age-expected milestones.

Inadequate physical growth in a child manifested by weight below the 2nd percentile for age/sex or a significant downward crossing of growth percentile lines, requiring evaluation of nutritional, medical, and psychosocial factors.

A convulsion triggered by fever in children aged 6 months to 5 years without evidence of CNS infection. Simple febrile seizures are generalized, last under 15 minutes, and carry an excellent prognosis.

Soft spots on an infant's skull where cranial bones have not yet fused. The anterior fontanelle normally closes by 12-18 months; the posterior fontanelle closes by 2-3 months. A bulging fontanelle may indicate increased intracranial pressure; a sunken fontanelle suggests dehydration.

The process of conferring immunity to a disease through administration of a vaccine, stimulating the immune system to produce antibodies and memory cells against specific pathogens.

A condition in which one segment of the intestine telescopes into an adjacent segment, causing bowel obstruction. Most common in children 6-36 months and typically involves the ileocecal junction.

Yellow discoloration of skin and sclera caused by elevated unconjugated bilirubin in newborns. Physiologic jaundice is common and benign; pathologic jaundice requires investigation and treatment with phototherapy or exchange transfusion to prevent kernicterus.

An acute systemic vasculitis of unknown etiology primarily affecting children under 5, characterized by prolonged fever and mucocutaneous findings. It is the leading cause of acquired heart disease in children in developed countries due to coronary artery aneurysm risk.

The first stool of a newborn, composed of materials ingested during intrauterine life including amniotic fluid, bile, and epithelial cells. It is typically dark green-black and passed within the first 24-48 hours of life.

A subspecialty of pediatrics focused on the medical care of newborn infants, particularly premature and critically ill neonates requiring intensive care.

Infection or inflammation of the middle ear, one of the most common pediatric diagnoses. Acute otitis media presents with ear pain, fever, and a bulging tympanic membrane and is most frequently caused by Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis.

A primitive neonatal reflex in which placing an object in the infant's palm causes the fingers to flex and grip. It is normally present at birth and disappears by 5-6 months as voluntary grasping develops.

An autosomal recessive inborn error of metabolism caused by deficiency of phenylalanine hydroxylase, leading to toxic accumulation of phenylalanine. Detected by newborn screening and treated with a phenylalanine-restricted diet to prevent intellectual disability.

The onset of secondary sexual characteristics before age 8 in girls or age 9 in boys. Central precocious puberty is GnRH-dependent and often idiopathic in girls; peripheral precocious puberty is GnRH-independent and requires evaluation for adrenal or gonadal pathology.

The most common cause of bronchiolitis and pneumonia in children under 1 year of age. It causes seasonal outbreaks (typically winter) and can be severe in premature infants and those with underlying cardiopulmonary disease. Prophylaxis with palivizumab or nirsevimab is available for high-risk infants.

The unexplained death of an apparently healthy infant under 1 year of age, typically during sleep. Risk reduction strategies include supine sleeping position, firm sleep surface, room-sharing without bed-sharing, and avoiding overheating, soft bedding, and smoke exposure.

A five-stage classification system for physical maturation during puberty based on development of secondary sexual characteristics: breast and pubic hair in females; genital and pubic hair in males.

The recommended timeline for administration of childhood vaccines established by advisory bodies such as the CDC's Advisory Committee on Immunization Practices (ACIP) and the WHO. The schedule is designed to provide protection at the earliest safe and effective age.