Pediatric Conditions - Comprehensive Overview

Complete tutorial on pediatric conditions including common childhood illnesses (ear infections, RSV, croup, hand-foot-mouth disease), congenital disorders, growth disorders, childhood cancers, ADHD, and asthma. Covers pathophysiology, diagnosis, and treatment from NIH and CDC sources.

This content is for informational purposes only. Always consult a healthcare professional.

Pediatric conditions encompass a wide range of disorders affecting children from infancy through adolescence. Children are not simply small adults; they have unique physiology, developmental considerations, age-specific disease patterns, and medication dosing requirements. This article provides comprehensive coverage of major pediatric conditions.

Common Childhood Illnesses

Acute Otitis Media (Ear Infection)

Parameter Detail
Definition Acute infection of the middle ear with rapid onset of signs/symptoms of middle ear inflammation and middle ear effusion
Peak age 6-24 months (most common); second peak 4-6 years
Pathophysiology Eustachian tube dysfunction (short, horizontal, immature in children) -> negative middle ear pressure -> fluid accumulation -> bacterial superinfection
Common pathogens S. pneumoniae (most common), H. influenzae (non-typeable), M. catarrhalis, Group A Strep, viruses (RSV, influenza, rhinovirus)
Risk factors Daycare attendance, bottle feeding (vs breastfeeding), pacifier use, smoke exposure, immunodeficiency, craniofacial abnormalities (cleft palate, Down syndrome), family history

AOM Diagnosis (AAP Guidelines)

Criteria Finding
Acute onset Rapid onset of symptoms (ear pain, fever, irritability, pulling at ears)
Middle ear effusion Bulging tympanic membrane, decreased mobility on pneumatic otoscopy, otorrhea
Inflammation Erythematous TM or otalgia

AOM Treatment

Age Severity Treatment
<6 months Any Amoxicillin 80-90 mg/kg/day x10 days
6-24 months Non-severe (unilateral, mild symptoms, <39C) Amoxicillin or observation (watchful waiting with safety net)
6-24 months Severe (bilateral, severe pain, fever >39C) Amoxicillin 80-90 mg/kg/day x10 days
>=24 months Non-severe Observation (watchful waiting) or amoxicillin x5-7 days
>=24 months Severe Amoxicillin x10 days
Treatment failure (48-72 hours) Amoxicillin-clavulanate (high-dose)
Penicillin allergy Cefdinir, cefuroxime, ceftriaxone (IM), clindamycin
Prevention Pneumococcal conjugate vaccine (PCV15, PCV20), influenza vaccine, avoid smoke exposure, breastfeeding, limit pacifier use

Respiratory Syncytial Virus (RSV)

Parameter Detail
Definition Single-stranded RNA virus (Paramyxoviridae, Pneumovirus genus) causing respiratory tract infections, most significant in infants
Seasonality Fall-winter (November-March in Northern hemisphere)
Transmission Respiratory droplets, fomites; survives on surfaces for hours
Incubation 4-6 days
Clinical presentation Mild URI (rhinitis, cough) to severe bronchiolitis/pneumonia; apnea (especially in infants <2 months, preterm)

RSV Severity and Risk Factors

Severity Features Management
Mild URI symptoms, mild cough, no respiratory distress Supportive care (hydration, suctioning)
Moderate Lower respiratory tract involvement (bronchiolitis: tachypnea, wheezing, crackles, retractions, nasal flaring), SpO2 90-94% Supportive care, nasal suctioning, oxygen if SpO2 <90%, trial of nebulized hypertonic saline (3%), consider HHFNC
Severe Respiratory distress, SpO2 <90%, apnea, poor feeding, lethargy, dehydration Hospitalization, oxygen, HHFNC or CPAP, IV fluids, mechanical ventilation (if failing)

RSV Risk Factors for Severe Disease

Risk Factor Relative Risk
Prematurity (<37 weeks) 2-3x
Chronic lung disease (BPD) 3-5x
Congenital heart disease (hemodynamically significant) 3-4x
Immunodeficiency 2-3x
Age <12 weeks at start of RSV season 2x
Daycare attendance 1.5x
Smoke exposure 1.5-2x

RSV Prevention and Treatment

Intervention Details
Supportive care Mainstay: nasal suctioning, fever control, adequate hydration, no routine bronchodilators, no steroids, no antibiotics (unless secondary infection)
Palivizumab (Synagis) Monoclonal antibody (monthly IM during RSV season) for high-risk infants (preterm <29 weeks, BPD, CHD)
Nirsevimab (Beyfortus) Single-dose monoclonal antibody for all infants entering first RSV season (new AAP recommendation)
RSV vaccine (maternal) RSVpreF (Abrysvo) vaccine given at 32-36 weeks gestation to protect infant through first 6 months
RSV vaccine (older adults) RSVPreF3 (Arexvy) or RSVpreF (Abrysvo) for >=60 years

Croup (Laryngotracheobronchitis)

Parameter Detail
Definition Viral infection of the upper airway (larynx, trachea, bronchi) causing subglottic edema and characteristic barking cough
Peak age 6 months - 3 years
Common pathogens Parainfluenza virus (types 1, 2, 3 - most common), RSV, influenza, adenovirus, rhinovirus, metapneumovirus
Incubation 2-6 days
Classic presentation Barking seal-like cough, inspiratory stridor, hoarseness, worse at night, preceded by URI symptoms 1-2 days; low-grade fever

Croup Severity and Treatment

Severity Features Management
Mild Barking cough only when agitated, no stridor at rest, no respiratory distress Outpatient: single dose dexamethasone 0.6 mg/kg (max 10 mg) PO/IM/IV; supportive care (cool mist, hydration, calm child)
Moderate Barking cough, stridor at rest, mild-moderate retractions, no cyanosis Dexamethasone as above; nebulized epinephrine (racemic 2.25% 0.5 mL or L-epinephrine 1:1000, 5 mL) if moderate distress; observe 2-4 hours after epinephrine
Severe Stridor at rest, severe retractions, cyanosis, lethargy, poor air entry, altered mental status Dexamethasone + nebulized epinephrine (may repeat); Heliox; ICU admission; intubation if impending respiratory failure

Hand-Foot-and-Mouth Disease (HFMD)

Parameter Detail
Definition Common viral exanthem caused by enteroviruses, characterized by fever, vesicular enanthem (mouth) and exanthem (hands, feet)
Peak age <5 years (most common); children and adults can be affected
Most common pathogens Coxsackievirus A16 (most common, mild); Enterovirus A71 (EV-A71, more severe, CNS complications)
Incubation 3-7 days
Transmission Fecal-oral, respiratory droplets, contact with vesicle fluid; highly contagious
Seasonality Summer and early fall
Clinical features Fever (1-2 days), sore throat, malaise; oral vesicles/ulcers (tongue, buccal mucosa, palate, ~5-10 lesions); cutaneous vesicles (palms, soles, buttocks, ~3-50 lesions, 3-7 mm, greyish, elliptical); rash may be papular/vesicular on knees, elbows, trunk

HFMD Complications

Complication Pathogen Features Management
Dehydration Any Painful oral ulcers -> poor intake Oral hydration (cold liquids, popsicles); analgesic mouth rinses (lidocaine/diphenhydramine/Maalox); IV fluids if severe
Viral meningitis/encephalitis EV-A71 (most common), CVA16 (rare) Fever, headache, myoclonus, ataxia, cranial nerve palsies, altered mental status, neurogenic pulmonary edema (EV-A71) Supportive care; ICU monitoring; parenteral hydration/analgesia; no specific antiviral
Cardiopulmonary failure EV-A71 Tachycardia, hypertension, pulmonary edema, cardiogenic shock ICU, inotropes, ventilation, IVIG (may be beneficial)
Onychomadesis Any Nail shedding 1-2 months after infection Self-limited; no treatment needed
HFMD treatment Supportive (fever control, hydration, pain management); no specific antiviral; isolation until lesions resolve

Immunization Schedule Summary (CDC 2024)

Age Vaccines
Birth HepB
1-2 months HepB
2 months RV, DTaP, IPV, Hib, PCV20 (or Prevnar 20/PCV15)
4 months RV, DTaP, IPV, Hib, PCV20
6 months DTaP, IPV, Hib, PCV20, COVID-19, influenza (annual starting at 6 months)
12-15 months MMR, VAR, PCV20 (booster if PCV13 received), Hib (booster), HepA (dose 1)
15-18 months DTaP (booster)
18-24 months HepA (dose 2)
4-6 years DTaP, IPV, MMR, VAR
11-12 years Tdap, HPV (2-3 doses), MenACWY
16 years MenACWY (booster), MenB (shared decision)

Congenital Disorders

Common Congenital Anomalies

Condition Incidence Etiology Key Features Management
Cleft lip and palate 1:700 Multifactorial (genetic + environmental), syndromic (Van der Woude, Stickler, Pierre Robin sequence) Cleft lip (unilateral/bilateral), cleft palate (submucous, soft, hard, complete) Surgical repair: lip at 3-6 months, palate at 9-18 months; multidisciplinary team (ENT, speech, orthodontics, genetics)
Congenital heart disease 1:100 Multifactorial, genetic (Down syndrome - AV canal, Turner - coarctation, DiGeorge - conotruncal), environmental (rubella, maternal diabetes, alcohol) VSD (most common, 30%), ASD, PDA, tetralogy of Fallot, transposition of great arteries, coarctation, HLHS, single ventricle Medical management (PGE for ductal-dependent lesions), surgical repair/correction, cardiac catheterization, heart transplant (HLHS, failed palliation)
Neural tube defects (NTD) 1:1,000 (declined with folic acid fortification) Multifactorial (folic acid deficiency, genetic, environmental, medications - valproate) Spina bifida (meningocele, myelomeningocele most common), anencephaly, encephalocele Prenatal folic acid (0.4 mg daily all women; 4 mg if prior NTD); prenatal surgical repair (MOMS trial); postnatal closure, CSF shunt for hydrocephalus, multidisciplinary care
Down syndrome (Trisomy 21) 1:700 (increases with maternal age) Non-disjunction (95%), translocation (4%), mosaicism (1%) Intellectual disability, hypotonia, flat facies, epicanthal folds, single palmar crease, CHD (AV canal, VSD), duodenal atresia, Hirschsprung, hearing loss, hypothyroidism, Alzheimer risk Multidisciplinary: cardiology, audiology, ophthalmology, endocrinology, developmental pediatrics; treat hypothyroidism, screen for celiac, CHD repair

Newborn Screening (Commonly Screened Conditions in US)

Condition Test Onset if Untreated Treatment
Phenylketonuria (PKU) Guthrie test (heel stick) Progressive intellectual disability by 3-6 months Phenylalanine-restricted diet (lifelong)
Congenital hypothyroidism TSH, T4 Irreversible intellectual disability by 3-6 months Levothyroxine (start immediately)
Cystic fibrosis IRT, DNA analysis Failure to thrive, recurrent respiratory infections CFTR modulators, pancreatic enzymes, airway clearance
Sickle cell disease Hemoglobin electrophoresis Vaso-occlusive crises, stroke risk, infection risk Hydroxyurea, vaccination, penicillin prophylaxis
Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency Tandem mass spectrometry Hypoglycemia, metabolic acidosis, sudden death Avoid prolonged fasting, L-carnitine, sick day management
Congenital adrenal hyperplasia (CAH) 17-OHP by heel stick Salt-wasting crisis (life-threatening), virilization Hydrocortisone, fludrocortisone, salt supplementation

Growth Disorders

Normal Growth Parameters

Parameter Normal Variation Abnormal Threshold Evaluation
Height velocity (1-3 years) 5-8 cm/year <5 cm/year (<2nd percentile) Bone age, growth chart review, endocrine workup (IGF-1, IGFBP-3, TSH, celiac screen)
Height velocity (3-10 years) 5-6 cm/year (pre-pubertal) <4.5 cm/year Same as above
Height velocity (10-14 years, puberty) 8-14 cm/year (peak) <6 cm/year (delayed puberty) Pubertal staging, bone age, GnRH/LH/FSH, sex steroids
Weight gain Follows growth curve percentile Crossing 2+ percentiles downward Medical history, dietary assessment, endocrine/metabolic workup
Head circumference Follows curve Crossing 2+ percentiles upward or downward Neuroimaging (if indicated), developmental assessment

Short Stature Etiologies

Category Cause Key Features
Normal variant Familial short stature Normal growth velocity, bone age = chronologic age, parents short
Constitutional delay of growth and puberty Delayed bone age, delayed puberty, family history of late bloomers, eventually normal adult height
Endocrine Growth hormone deficiency Slow growth velocity, delayed bone age, low IGF-1/IGFBP-3, low GH on stimulation testing; may have midline defects, hypoglycemia
Endocrine Hypothyroidism Growth deceleration, delayed bone age, elevated TSH, low T4; other hypothyroid symptoms
Endocrine Cushing syndrome Growth failure, weight gain, moon facies, striae, elevated cortisol
Genetic Turner syndrome (45,X) Short stature, webbed neck, broad chest, low hairline, gonadal dysgenesis; consider in all girls with unexplained short stature
Genetic Noonan syndrome Short stature, webbed neck, CHD (pulmonic stenosis), pectus deformity, intellectual disability
Skeletal dysplasia Achondroplasia Rhizomelic shortening (proximal limbs), macrocephaly, frontal bossing, trident hands; most common skeletal dysplasia
Chronic disease Celiac disease Malabsorption, abdominal pain, short stature, anemia, positive tTG
Chronic disease IBD Growth failure may precede GI symptoms; poor nutrition, inflammation
Chronic disease CKD Growth failure due to metabolic acidosis, anemia, malnutrition; improve with treatment
Psychosocial Psychosocial dwarfism (deprivation) Growth failure, delayed bone age, abnormal social interactions, improve with change in environment

Growth Hormone Therapy Indications

Indication FDA Approval Expected Height Gain
Growth hormone deficiency Yes Variable (depends on degree of deficiency and age at diagnosis)
Turner syndrome Yes 5-8 cm
Chronic kidney disease Yes 4-6 cm
Noonan syndrome Yes 3-5 cm
Small for gestational age (SGA) without catch-up by age 2-4 Yes 5-7 cm
Prader-Willi syndrome Yes Improved body composition
Idiopathic short stature (height SDS < -2.25) Yes (controversial, high cost, modest benefit) 3-5 cm

Childhood Cancers

Type Peak Age Frequency Key Features 5-Year Survival
ALL (Acute Lymphoblastic Leukemia) 2-5 years 25% of childhood cancers (most common) B-cell (85%) > T-cell; pallor, fatigue, bruising, fever, bone pain, hepatosplenomegaly; WBC >50K is high-risk >90% (best outcomes in developed world)
Brain tumors Variable 20% Most common solid tumor; astrocytoma/pilocytic astrocytoma (most common, good prognosis), medulloblastoma (posterior fossa, peak 3-8), ependymoma, brainstem glioma 75-85% (varies by type)
Neuroblastoma <5 years (median 18 months) 8% Abdominal mass (adrenal), proptosis (periorbital metastases), opsoclonus-myoclonus; MYCN amplification is poor prognostic 50-80% (age-dependent; infants >90%)
Wilms tumor (nephroblastoma) 3-4 years 5% Abdominal mass, hematuria, hypertension; associated with WAGR, Beckwith-Wiedemann, Denys-Drash syndromes >90%
Hodgkin lymphoma 15-19 years (bimodal also: 25-30) 5% Painless lymphadenopathy (cervical, supraclavicular), B symptoms; nodular sclerosis most common; good prognosis >95%
Non-Hodgkin lymphoma 7-11 years 6% Burkitt (most common), DLBCL, lymphoblastic, anaplastic large cell; abdominal, mediastinal, nodal 80-90%
Osteosarcoma 10-20 years (growth spurt) 3% Long bone metaphysis (distal femur, proximal tibia), pain, swelling, Codman triangle, sunburst appearance 60-70%
Ewing sarcoma 10-15 years 2% Diaphysis (femur, pelvis, chest wall), t(11;22) EWSR1-FLI1; primitive neuroectodermal tumor 70-80%
Rhabdomyosarcoma 2-6 years, 15-19 3% Most common soft tissue sarcoma; head/neck, genitourinary, extremities; PAX3/PAX7-FOXO1 fusion 70%
Retinoblastoma <2 years 2% Leukocoria (cat’s eye reflex), strabismus; RB1 gene; hereditary (40%, bilateral, early) vs sporadic (60%, unilateral) >95%
Germ cell tumors Variable 3% Sacrococcygeal (infants), ovarian, testicular, mediastinal; increased AFP, beta-hCG >90%

Common Oncologic Emergencies in Children

Emergency Common in Presentation Management
Tumor lysis syndrome (TLS) ALL, Burkitt lymphoma Hyperuricemia, hyperkalemia, hyperphosphatemia, hypocalcemia, AKI, cardiac arrhythmias Rasburicase, aggressive IV hydration, allopurinol, management of electrolytes, dialysis if needed
Superior vena cava syndrome (SVCS) ALL, NHL, mediastinal masses Facial/neck edema, stridor, dyspnea, headache, jugular venous distension; anesthesia risk (airway compromise) Corticosteroids, radiation (low dose); avoid biopsy under general anesthesia
Febrile neutropenia Any chemo Fever (single >38.3C or sustained >38C x1 hour) in neutropenic patient (ANC <500) Broad-spectrum IV antibiotics (cefepime, piperacillin-tazobactam), growth factors (G-CSF) if prolonged
Spinal cord compression Neuroblastoma, sarcomas, lymphoma Back pain, limb weakness, bowel/bladder dysfunction, sensory level Corticosteroids, emergent radiation or neurosurgical decompression

Attention-Deficit/Hyperactivity Disorder (ADHD)

Parameter Detail
Definition Neurodevelopmental disorder characterized by persistent pattern of inattention and/or hyperactivity-impulsivity that interferes with functioning or development
Prevalence 5-10% of children (most common neurodevelopmental disorder); M:F 3:1 in children
Age of onset Symptoms before age 12 (required per DSM-5)
Pathophysiology Dysregulation of dopamine and norepinephrine in prefrontal cortex, executive function networks, frontostriatal circuitry; strong genetic component (heritability 70-80%)

ADHD Subtypes (DSM-5)

Subtype Predominant Symptoms Frequency
Predominantly inattentive Inattention (>=6 of 9 symptoms): careless mistakes, difficulty sustaining attention, not listening, not following through, disorganized, avoids sustained mental effort, loses things, easily distracted, forgetful 20-30%
Predominantly hyperactive-impulsive Hyperactivity-impulsivity (>=6 of 9 symptoms): fidgets, leaves seat, runs/climbs inappropriately, unable to play quietly, on the go, talks excessively, blurts answers, difficulty waiting turn, interrupts 10-15%
Combined Both inattention and hyperactivity-impulsivity criteria met 50-75% (most common)

ADHD Treatment

Intervention Examples Notes
Behavioral therapy (preschool, mild) Parent training in behavior management, classroom management, organizational skills training First-line for preschool (age 4-5); recommended as adjunct for all ages
Stimulants (first-line pharmacotherapy) Methylphenidate (Ritalin, Concerta, Daytrana, Metadate) - short and long-acting; Amphetamine (Adderall, Vyvanse, Dexedrine, Evekeo) Highly effective (70-80% response); monitor appetite, sleep, growth, BP, HR; no increased risk of tics or future substance abuse when treated
Non-stimulants (second-line) Atomoxetine (SNRI), guanfacine ER (alpha-2 agonist), clonidine ER (alpha-2 agonist) For poor response/intolerance to stimulants, comorbid anxiety/tics; slower onset of action; effective for symptom control
School interventions 504 Plan, IEP, preferential seating, extended time, reduced workload, breaks Legal rights under IDEA and ADA
Comorbidity management Treat coexisting conditions (anxiety, depression, ODD, learning disabilities) 60-80% of children with ADHD have at least one comorbid condition

Pediatric Asthma

Refer to the Respiratory Diseases article for comprehensive asthma information.

Key Pediatric Considerations

Aspect Children Adults
Diagnosis Clinical (wheezing, cough, dyspnea, chest tightness) + family history + therapeutic trial; spirometry from age 5-6 Spirometry + bronchodilator reversibility
Triggers URI (most common), allergens, exercise, cold air, emotions, tobacco smoke Allergens, exercise, cold air, NSAIDs, beta-blockers, occupational, less viral
Differential Viral-induced wheezing, bronchiolitis, foreign body (sudden onset, unilateral), GERD, cystic fibrosis, croup, vocal cord dysfunction, tracheomalacia, congenital anomalies, aspiration COPD, CHF, vocal cord dysfunction, PE, hypersensitivity pneumonitis, chronic cough from ACEi, GERD
Medication dosing Weight-based (mg/kg) Standard dosing
Inhaler device Metered dose inhaler (MDI) + spacer (preferred for all ages) or nebulizer for young children MDI, DPI (preferred for coordination issues)
Growth monitoring Monitor height/weight during treatment (ICS may cause growth deceleration, usually minimal and not progressive) Not applicable
Transition to adult care Begin transition at age 12-14; complete transfer at 18-21
Acute severity classification (NAEPP EPR-3) Mild: normal mental status, slight tachypnea, wheeze end-expiratory; Moderate: agitation, tachypnea, wheeze throughout, retractions; Severe: agitation, marked tachypnea, severe retractions, air entry poor, cyanosis; Impending respiratory failure: lethargic/drowsy, silent chest, no respiratory drive, bradycardia Similar but with risk stratification (PEFR)

Factors Predicting Persistent Asthma in Wheezing Children (API - Asthma Predictive Index)

Major Criteria Minor Criteria
Parental MD diagnosis of asthma MD diagnosis of allergic rhinitis
MD diagnosis of atopic dermatitis Wheezing unrelated to URI
Aeroallergen sensitization Eosinophilia >=4%

Interpretation: 1 major OR 2 minor criteria = positive API (predicts asthma persistence at school age).