B

Bacillus Calmette-Guérin (BCG) Vaccine

• Definition: A live-attenuated vaccine derived from Mycobacterium bovis used to protect against tuberculosis (TB).

• Use in Pediatrics:

  • Routinely given at birth in high-TB-burden countries.

  • Prevents severe forms of TB (miliary TB, tuberculous meningitis) in children.

• Administration: Intradermal injection, typically in the right upper arm.

• Complications: Local ulceration, regional lymphadenitis, disseminated BCG infection (rare, usually in immunodeficient children).

• Clinical Relevance: Essential in pediatric immunization schedules in Africa and Asia.

Bacteremia

• Definition: Presence of viable bacteria in the bloodstream.

• Etiology in Pediatrics:

  • Neonates: Group B Streptococcus, E. coli.

  • Infants/children: S. pneumoniae, H. influenzae, N. meningitidis.

• Clinical Features: Fever, irritability, poor feeding, lethargy, or septic shock.

• Investigations: Blood culture, CBC, CRP, procalcitonin.

• Management: Empirical IV antibiotics (ampicillin + gentamicin in neonates; ceftriaxone ± vancomycin in older children).

• Complications: Sepsis, meningitis, endocarditis, osteomyelitis.

Ballard Scoring System

• Definition: A clinical scoring system to estimate gestational age in newborns.

• Parameters:

  • Neuromuscular: Posture, square window, arm recoil, popliteal angle, scarf sign, heel-to-ear.

  • Physical: Skin, lanugo, plantar creases, breast tissue, eye/ear development, genitalia.

• Use: Essential in low-resource settings when accurate maternal dating is unavailable.

• Relevance: Guides neonatal care and interventions (e.g., feeding, thermoregulation).

Barlow Maneuver

• Definition: A physical examination maneuver for detecting developmental dysplasia of the hip (DDH) in infants.

• Technique: With the infant supine, hips flexed at 90°, the examiner adducts the thigh and applies gentle posterior pressure. A palpable “clunk” indicates dislocation.

• Companion Test: Ortolani maneuver (to reduce a dislocated hip).

• Relevance: Early detection prevents long-term disability and hip osteoarthritis.

Bartter Syndrome

• Definition: A group of rare inherited renal tubular disorders causing defective sodium, potassium, and chloride reabsorption in the thick ascending limb of Henle.

• Types: Neonatal, classic, antenatal, with varying severity.

• Clinical Features:

  • Polyuria, polydipsia, growth failure.

  • Hypokalemic metabolic alkalosis.

  • Nephrocalcinosis.

• Investigations:

  • Serum electrolytes (low K⁺, metabolic alkalosis).

  • Urinary chloride high.

• Management: Potassium supplementation, NSAIDs (indomethacin), ACE inhibitors, spironolactone.

Behavioral Disorders (Pediatrics)

• Examples:

  • ADHD (Attention-Deficit/Hyperactivity Disorder).

  • Conduct Disorder.

  • Oppositional Defiant Disorder.

• Clinical Impact: Affects school performance, peer relationships, family dynamics.

• Management: Multidisciplinary (behavioral therapy, parental training, pharmacotherapy for ADHD).

Biliary Atresia

• Definition: Progressive fibro-obliterative disease of extrahepatic bile ducts in infants.

• Presentation: Persistent neonatal jaundice (>14 days), pale stools, dark urine, hepatomegaly.

• Investigations:

  • Ultrasound (absent/abnormal gallbladder).

  • HIDA scan (no excretion into intestine).

  • Liver biopsy (biliary obstruction).

• Management:

  • Kasai portoenterostomy (early surgery crucial).

  • Liver transplant in advanced disease.

• Complications: Cirrhosis, portal hypertension, liver failure.

Birth Asphyxia (Perinatal Asphyxia)

• Definition: Impaired gas exchange leading to hypoxemia, hypercapnia, and metabolic acidosis around the time of birth.

• Risk Factors: Prolonged labor, cord prolapse, placental abruption, preeclampsia.

• Clinical Grading (Apgar score at 1 and 5 min).

• Complications:

  • Hypoxic-Ischemic Encephalopathy (HIE).

  • Multiorgan dysfunction (renal failure, NEC, seizures).

• Management: Neonatal resuscitation per NRP guidelines, supportive intensive care, therapeutic hypothermia.

• Prevention: Skilled birth attendants, intrapartum monitoring.

Blalock-Taussig Shunt

• Definition: A palliative surgical procedure for cyanotic congenital heart disease (e.g., Tetralogy of Fallot).

• Procedure: Anastomosis between subclavian artery and pulmonary artery to increase pulmonary blood flow.

• Indications: Severe cyanosis awaiting definitive repair.

• Relevance: Life-saving in neonates/infants with duct-dependent lesions.

Bronchiolitis

• Definition: Acute viral lower respiratory tract infection affecting small airways in infants (<2 years).

• Common Cause: Respiratory syncytial virus (RSV).

• Clinical Features: Cough, tachypnea, wheezing, nasal flaring, intercostal retractions.

• Management:

  • Supportive: Oxygen, hydration, nasal suctioning.

  • No routine antibiotics or steroids.

  • High-flow nasal cannula or CPAP in severe cases.

• Complications: Recurrent wheezing, apnea (esp. in preterm infants).

Bronchopulmonary Dysplasia (BPD)

• Definition: Chronic lung disease in preterm infants requiring oxygen supplementation beyond 28 days of life.

• Risk Factors: Prematurity, prolonged mechanical ventilation, oxygen toxicity.

• Clinical Features: Tachypnea, hypoxemia, hypercapnia, growth retardation.

• Investigations: Chest X-ray (ground glass appearance, hyperinflation).

• Management:

  • Oxygen therapy, diuretics, bronchodilators.

  • Nutritional support.

  • Prevention: Gentle ventilation strategies, antenatal steroids.

• Complications: Pulmonary hypertension, recurrent respiratory infections.

Brudzinski Sign

• Definition: A clinical sign of meningeal irritation.

• Technique: Passive neck flexion → involuntary flexion of hips and knees.

• Seen in: Pediatric meningitis, subarachnoid hemorrhage.

• Relevance: Supports diagnosis but not definitive.

Burns (Pediatric Considerations)

• Causes: Scalds (most common), flame burns, electrical, chemical.

• Assessment:

  • Rule of Nines adjusted for children (larger head proportion).

  • Depth: Superficial, partial thickness, full thickness.

• Management:

  • Airway, breathing, circulation (fluid resuscitation using Parkland formula).

  • Pain control, wound care, infection prevention.

• Complications: Hypovolemia, sepsis, contractures.

• Prevention: Household safety, parental education.