Common Pediatric Diseases and Disorders
A newborn emerges from the delivery room with a cleft lip, club feet, and a heart murmur. Another infant is diagnosed prenatally with spina bifida. A third baby presents at 24 hours with bilious vomiting—imaging reveals duodenal atresia. These are congenital anomalies: structural or functional abnormalities present at birth that occur during intrauterine development. They affect 2-3% of all births, are the leading cause of infant mortality in developed countries, and range from minor cosmetic issues to life-threatening defects requiring immediate intervention.
📋 Definitions and Classifications
Understanding Congenital Anomalies
Key Definitions
- Congenital Anomaly: Any structural or functional abnormality present at birth
- Major Anomaly: Causes significant medical, surgical, or cosmetic problems
- Minor Anomaly: No significant medical or cosmetic impact (ear tags, extra digits)
Pathophysiological Types
- Malformation: Primary structural defect from abnormal development (cleft lip, spina bifida)
- Deformation: Abnormal shape from mechanical forces (clubfoot from oligohydramnios)
- Disruption: Destruction of previously normal tissue (amniotic band syndrome)
- Dysplasia: Abnormal organization of cells within tissue (skeletal dysplasias)
- Syndrome: Multiple anomalies with single underlying cause (Down syndrome)
📊 Epidemiology
Global Burden and Common Types
Global Statistics
- Incidence: 2-3% of all live births
- Leading cause of infant mortality in developed countries (20% of infant deaths)
- Global burden: 300,000+ deaths in first 28 days annually
Most Common Types
- Congenital heart defects: 8 per 1,000
- Neural tube defects: 1-2 per 1,000
- Orofacial clefts: 1-2 per 1,000
- Clubfoot: 1 per 1,000
- Down syndrome: 1 per 700
🔬 Causes and Teratogens
Etiology of Congenital Anomalies
Causes
- Genetic (30-40%): Chromosomal abnormalities, single gene mutations
- Environmental (5-10%): Teratogens, maternal conditions
- Multifactorial (20-30%): Genetic predisposition + environmental factors
- Unknown (40-50%)
Medications
- Isotretinoin: Craniofacial, cardiac, CNS defects
- Valproate: Neural tube defects, facial dysmorphisms
- Warfarin: Nasal hypoplasia, stippled epiphyses
- ACE inhibitors: Renal dysgenesis (2nd/3rd trimester)
Infections (TORCH)
- Toxoplasmosis: Hydrocephalus, intracranial calcifications
- Rubella: Cataracts, heart defects, deafness
- CMV: Microcephaly, hearing loss
- HSV: Skin scarring, microcephaly
Maternal Conditions
- Diabetes: Cardiac defects, neural tube defects
- Phenylketonuria: Microcephaly, heart defects
- Hyperthermia: Neural tube defects
💊 Prevention Strategies
- Folic acid supplementation (400-800 mcg daily)—reduces neural tube defects by 50-70%
- Optimize chronic conditions (diabetes control)
- Avoid teratogens (review medications)
- Vaccination (rubella immunity)
- Genetic counseling if family history
🧠 Neural Tube Defects
Abnormal Neural Tube Closure
Spina Bifida Types
- Spina bifida occulta: Bony defect only, skin intact—usually asymptomatic
- Meningocele: Meninges protrude through defect—better prognosis
- Myelomeningocele: Spinal cord and meninges protrude—most severe
Myelomeningocele Management
- Surgical closure within 24-48 hours
- VP shunt for hydrocephalus (80-90%)
- Multidisciplinary care (neurosurgery, orthopedics, urology)
- Prenatal repair available—reduces need for shunting
🚨 Other Neural Tube Defects
- Anencephaly: Absence of forebrain and skull vault—incompatible with life
- Encephalocele: Herniation of brain tissue through skull defect
- Arnold-Chiari II Malformation: Hindbrain herniation—associated with myelomeningocele
💧 Hydrocephalus
Excessive CSF Accumulation
Causes
- Congenital: Aqueductal stenosis, Dandy-Walker malformation
- Acquired: Intraventricular hemorrhage, infection, tumors
Presentation
- Macrocephaly (rapidly crossing percentiles)
- Bulging fontanelle, split sutures
- "Setting sun" sign (eyes deviate downward)
- Irritability, vomiting, developmental delay
Treatment
- VP shunt (ventriculoperitoneal)
- Endoscopic third ventriculostomy (ETV)
- Lifelong monitoring for shunt malfunction/infection
👄 Orofacial Clefts
Cleft Lip and Palate
Types and Timing
- Cleft Lip: Failure of maxillary and nasal fusion (weeks 5-6)
- Cleft Palate: Failure of palatal shelf fusion (weeks 8-9)
- Incidence: 1 in 700-1,000 births
Associated Problems
- Feeding difficulties (especially cleft palate)
- Speech problems (hypernasal speech)
- Ear infections (Eustachian tube dysfunction)
- Dental problems (malocclusion)
- Psychosocial issues
🩺 Management Approach
- Specialized feeding: Haberman or Pigeon bottles
- Surgical repair: Lip at 3-6 months, palate at 9-18 months
- Team approach: Surgeon, orthodontist, speech therapist, ENT
- Outcomes: Good with comprehensive care
🍽️ Gastrointestinal Anomalies
GI Tract Abnormalities
EA/TEF
Esophageal Atresia
Duodenal Atresia
Double Bubble
Imperforate Anus
Anal Malformation
Gastroschisis
Bowel Herniation
Omphalocele
Umbilical Hernia
Esophageal Atresia/TEF
- Presentation: Excessive drooling, choking with feeding
- Diagnosis: NG tube coils in proximal pouch
- Association: VACTERL (50%)
- Treatment: Surgical repair, survival >95%
Duodenal Atresia
- Presentation: Bilious vomiting within 24 hours
- X-ray: "Double bubble" sign
- Association: Down syndrome (30%)
- Treatment: Surgical bypass
Anorectal Malformations
- Presentation: No anus visible, no meconium
- Classification: High vs. Low (better prognosis)
- Association: VACTERL
- Treatment: Surgical repair, may need colostomy
Abdominal Wall Defects
- Gastroschisis: No sac, usually isolated, better prognosis
- Omphalocele: Covered by sac, associated anomalies common
- Management: Surgical repair, protect exposed bowel
🔑 High-Yield Summary - Part 1
| Anomaly | Key Features | Management |
|---|---|---|
| Myelomeningocele | Spinal cord protrusion, hydrocephalus risk | Surgical closure within 48h, VP shunt, multidisciplinary care |
| Cleft Lip/Palate | Feeding/speech difficulties, ear infections | Special bottles, surgical repair, speech therapy |
| EA/TEF | Drooling, choking, polyhydramnios | NPO, surgical repair, screen for VACTERL |
| Duodenal Atresia | Bilious vomiting, double bubble sign | Surgical bypass, screen for Down syndrome |
🎯 Key Takeaways - Part 1
- Congenital anomalies affect 2-3% of births and are the leading cause of infant mortality
- Folic acid supplementation (400-800 mcg daily) reduces neural tube defects by 50-70%
- Neural tube defects range from asymptomatic spina bifida occulta to severe myelomeningocele
- Cleft lip/palate requires specialized feeding and multidisciplinary surgical/speech care
- Bilious vomiting in newborns indicates surgical emergency until proven otherwise
- VACTERL association requires screening for multiple anomalies when one is identified
- Gastroschisis has better prognosis than omphalocele due to fewer associated anomalies
- Polyhydramnios suggests GI obstruction; oligohydramnios suggests renal anomalies