const {
  Document, Packer, Paragraph, TextRun, Table, TableRow, TableCell,
  HeadingLevel, AlignmentType, BorderStyle, WidthType, ShadingType,
  PageNumber, NumberFormat, convertInchesToTwip, UnderlineType
} = require('docx');
const fs = require('fs');

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// DATA
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const topics = [
  {
    name: "TOPIC 1: NEONATOLOGY",
    color: "1F4E79",
    pareto: "HIGH YIELD (Pareto Tier 1 — 80% exam weight)",
    feynman: {
      coreIdea: "The newborn is not a small adult. It has unique physiology: fetal circulation transitions, immature thermoregulation, limited glycogen stores, and a developing immune system. Think of the neonate as someone who just moved from a warm, oxygenated water world (uterus) to a cold, air-breathing, microbially exposed world.",
      highYield: [
        "Apgar score: assessed at 1 min (resuscitation need) & 5 min (prognosis). Scoring: HR, Resp effort, Muscle tone, Reflex irritability, Color. Score ≥7 = normal; <7 = resuscitation.",
        "Delayed cord clamping: ≥30–60 sec for vigorous term/preterm infants. NOT in monochorionic twins, IUGR <3rd %ile with reversed EDV, CDH, abdominal wall defects.",
        "ETT size quick formula: weight(kg) + 6 = depth in cm; size = 2.5 mm (<30 wGA), 3.0 (30-34), 3.5 (>35).",
        "Neonatal jaundice: Physiologic = starts day 2–3, peaks day 3–5, resolves day 7–10. Pathologic = starts <24 hrs, total bilirubin >15 mg/dL, or direct bilirubin >2 mg/dL.",
        "Neonatal hypoglycemia: Blood glucose <45 mg/dL in term neonate. Causes: IDM (maternal diabetes), SGA, prematurity, Beckwith-Wiedemann syndrome. Rx: IV dextrose if symptomatic.",
        "RDS (hyaline membrane disease): preterm, surfactant deficiency, ground-glass opacity on CXR, ground-glass + air bronchograms. Treatment: surfactant + CPAP.",
        "Meconium aspiration: post-term babies, meconium-stained fluid. No routine tracheal suctioning in vigorous infants.",
        "NEC: necrotizing enterocolitis — preterm, formula-fed, pneumatosis intestinalis on X-ray = pathognomonic. TX: NPO, IV antibiotics ± surgery.",
        "Neonatal sepsis: Early onset (<72 hrs): GBS, E. coli. Late onset (>72 hrs): Staph epidermidis, Staph aureus. Rx: Ampicillin + Gentamicin (early).",
        "Transient tachypnea of newborn (TTN): C-section babies, resolves 24–72 hrs, wet lung/retained fluid on CXR."
      ]
    },
    questions: [
      {
        q: "A 28-week preterm neonate develops increasing respiratory distress within 4 hours of birth. Chest X-ray shows bilateral ground-glass opacities with air bronchograms. Which is the most likely diagnosis?",
        opts: ["A. Meconium aspiration syndrome", "B. Transient tachypnea of newborn", "C. Respiratory distress syndrome (hyaline membrane disease)", "D. Congenital pneumonia"],
        ans: "C",
        exp: "RDS (hyaline membrane disease) is caused by surfactant deficiency in preterm infants. It presents within hours of birth with bilateral ground-glass opacities and air bronchograms. TTN occurs in term/near-term babies born via C-section. Meconium aspiration is a post-term phenomenon. [Harriet Lane Handbook, 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A neonate born at 35 weeks develops jaundice on day 1 of life. Total serum bilirubin is 18 mg/dL. What is the most likely type of jaundice?",
        opts: ["A. Physiologic jaundice", "B. Breast milk jaundice", "C. Pathologic jaundice", "D. ABO incompatibility jaundice"],
        ans: "C",
        exp: "Pathologic jaundice appears within 24 hours of birth. Any jaundice in the first 24 hours is pathologic by definition. TSB >15 mg/dL in a preterm infant is also pathologic. Physiologic jaundice appears after day 2. [Harriet Lane Handbook, 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A term neonate of a diabetic mother is found to have blood glucose of 35 mg/dL on routine screening at 1 hour of life. He appears jittery. What is the immediate management?",
        opts: ["A. Oral glucose gel", "B. IV dextrose 10% bolus", "C. IM glucagon injection", "D. Formula feeding and recheck in 1 hour"],
        ans: "B",
        exp: "Symptomatic neonatal hypoglycemia (glucose <45 mg/dL with symptoms such as jitteriness, seizure) requires IV dextrose 10% at 2 mL/kg bolus followed by maintenance infusion. Infants of diabetic mothers have hyperinsulinism causing rapid glucose drop after birth. [Harriet Lane Handbook, 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A neonate born at 26 weeks gestation requires intubation. What is the appropriate ETT depth of insertion?",
        opts: ["A. 6 cm", "B. 7 cm", "C. 8 cm", "D. 9 cm"],
        ans: "B",
        exp: "ETT depth = weight (kg) + 6. A 26-week neonate typically weighs approximately 800 g (~1 kg), so depth = 1 + 6 = 7 cm. ETT size = 2.5 mm for <30 weeks. [Harriet Lane Handbook, 23e]",
        pareto: "★★ TIER 2"
      },
      {
        q: "Which of the following is PATHOGNOMONIC for necrotizing enterocolitis (NEC) on abdominal X-ray?",
        opts: ["A. Gasless abdomen", "B. Free air under the diaphragm", "C. Pneumatosis intestinalis", "D. Dilated bowel loops"],
        ans: "C",
        exp: "Pneumatosis intestinalis (gas in the bowel wall) is pathognomonic for NEC. It represents gas produced by bacteria invading the necrotic bowel wall. Free air indicates perforation (surgical emergency). NEC primarily affects preterm, formula-fed infants. [Harriet Lane Handbook, 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A neonate develops signs of sepsis at 24 hours of life. Which organisms are most likely responsible?",
        opts: ["A. Staphylococcus epidermidis and Candida", "B. Group B Streptococcus and E. coli", "C. Klebsiella and Pseudomonas", "D. Listeria and MRSA"],
        ans: "B",
        exp: "Early-onset neonatal sepsis (<72 hours) is caused primarily by GBS (Group B Streptococcus) and E. coli. GBS colonizes the maternal genital tract. Late-onset sepsis (>72 hrs) is caused by Staph epidermidis (especially in NICU/catheter-related). Empiric treatment: Ampicillin + Gentamicin. [Harriet Lane Handbook, 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "An infant born by elective C-section at 39 weeks develops transient tachypnea. Which pathophysiology best explains this condition?",
        opts: ["A. Surfactant deficiency", "B. Retained fetal lung fluid", "C. Aspiration of meconium", "D. Pulmonary hypertension"],
        ans: "B",
        exp: "TTN (transient tachypnea of newborn) results from delayed clearance of fetal lung fluid. Normally, labor contractions and catecholamine surges promote lung fluid reabsorption. C-section babies miss this process. It is self-limiting, resolving in 24–72 hours. CXR shows 'wet lungs' / fluid in fissures. [Harriet Lane Handbook, 23e]",
        pareto: "★★ TIER 2"
      },
      {
        q: "A term neonate has an Apgar score of 4 at 1 minute and 6 at 5 minutes. What is the appropriate next step?",
        opts: ["A. Observe and repeat scoring", "B. Administer oxygen and stimulate", "C. Immediate intubation", "D. Admit to NICU for observation only"],
        ans: "B",
        exp: "Apgar 4–6 indicates moderate depression. Initial management = oxygen administration + tactile stimulation. A score <4 at 1 min requires immediate resuscitation (PPV). The 5-minute score predicts prognosis better than the 1-minute score. [Harriet Lane Handbook, 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "Delayed umbilical cord clamping is CONTRAINDICATED in which of the following situations?",
        opts: ["A. Preterm infant born at 32 weeks", "B. Term vigorous infant", "C. Monochorionic twin pregnancy", "D. Infant born at 36 weeks by C-section"],
        ans: "C",
        exp: "Delayed cord clamping is contraindicated in monochorionic twins due to risk of twin-to-twin transfusion. Other contraindications: discordant twins >25%, IUGR <3rd percentile with reversed end-diastolic flow, placental abruption, uterine rupture. [Harriet Lane Handbook, 23e]",
        pareto: "★★ TIER 2"
      },
      {
        q: "A preterm infant at 30 weeks shows clinical and radiological features of RDS. What is the first-line treatment?",
        opts: ["A. High-flow nasal cannula oxygen", "B. Intubation and mechanical ventilation only", "C. Exogenous surfactant therapy + CPAP", "D. Inhaled nitric oxide"],
        ans: "C",
        exp: "RDS is treated with exogenous surfactant (Poractant alfa / Beractant) administered intratracheally, along with CPAP (continuous positive airway pressure) to maintain functional residual capacity. Antenatal corticosteroids (Betamethasone) accelerate fetal lung maturity. [Harriet Lane Handbook, 23e]",
        pareto: "★★★ TIER 1"
      }
    ]
  },
  {
    name: "TOPIC 2: ENDOCRINOLOGY",
    color: "833C00",
    pareto: "HIGH YIELD (Pareto Tier 1 — 80% exam weight)",
    feynman: {
      coreIdea: "Pediatric endocrinology revolves around hormone deficiency vs. excess and their effects on growth and metabolism. Think of hormones as volume knobs — congenital hypothyroidism turns off the 'brain development' knob; congenital adrenal hyperplasia turns up the 'androgen' knob while turning off cortisol. The key to any endo question is: which gland, what hormone, deficiency or excess?",
      highYield: [
        "Congenital hypothyroidism (CH): Most common preventable cause of intellectual disability. Cause: thyroid dysgenesis (most common). Screen: TSH + T4 at 24–72 hrs. Features: prolonged jaundice, umbilical hernia, macroglossia, coarse facies, constipation, hypotonia, large fontanelles. Tx: Levothyroxine ASAP.",
        "Congenital adrenal hyperplasia (CAH): 21-hydroxylase deficiency (most common, 95%). Results in cortisol ↓, aldosterone ↓, androgens ↑. Salt-wasting crisis in males. Girls: virilization (ambiguous genitalia). Lab: 17-OH progesterone ↑. Rx: Hydrocortisone.",
        "Type 1 DM in children: Autoimmune destruction of beta cells. Polyuria, polydipsia, polyphagia, weight loss. DKA (pH <7.3, bicarb <15, ketones) is most common presentation. Rx: Insulin.",
        "Growth hormone deficiency: Short stature, delayed bone age, mid-facial hypoplasia, micropenis (males). Diagnosis: IGF-1 low, GH stimulation test. Rx: recombinant GH.",
        "Precocious puberty: Girls <8 yrs, Boys <9 yrs. Central (GnRH-dependent) vs. peripheral. Most common in girls = idiopathic central. Most common in boys = organic/CNS cause. MRI brain for all boys + girls if <6 yrs. Rx: GnRH agonist.",
        "Diabetes insipidus: Central (ADH deficiency) vs. nephrogenic (ADH resistance). Features: polyuria, polydipsia, low specific gravity urine, hypernatremia. Water deprivation test differentiates. Central Rx: DDAVP.",
        "Hypothyroidism in children: Acquired → Hashimoto thyroiditis (most common). Autoimmune, females, painless goiter, TPO antibodies +.",
        "Cushing syndrome: Exogenous steroids most common cause. Features: moon face, buffalo hump, striae, hypertension, growth failure. Endogenous: ACTH-producing pituitary adenoma = Cushing disease.",
        "Neonatal thyroid: T4 is critical for brain myelination in first 3 years. Universal newborn screening mandatory. False-positive TSH elevation seen in prematurity.",
        "Ambiguous genitalia workup: Karyotype first, then 17-OHP, electrolytes, pelvic ultrasound."
      ]
    },
    questions: [
      {
        q: "A 3-week-old infant presents with prolonged jaundice, constipation, macroglossia, and a large posterior fontanelle. TSH is markedly elevated. What is the most likely diagnosis?",
        opts: ["A. Down syndrome", "B. Congenital hypothyroidism", "C. Neonatal hepatitis", "D. Galactosemia"],
        ans: "B",
        exp: "Congenital hypothyroidism presents with prolonged jaundice (>2 weeks), constipation, macroglossia, large fontanelles, hypotonia, and umbilical hernia. Elevated TSH with low T4 confirms primary hypothyroidism. Universal newborn screening detects this before symptoms appear. Immediate levothyroxine prevents intellectual disability. [Harriet Lane Handbook + Harrison's 22e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 5-day-old male presents with vomiting, poor feeding, and shock. Electrolytes show hyponatremia and hyperkalemia. 17-OH progesterone is markedly elevated. What is the most likely diagnosis?",
        opts: ["A. Congenital adrenal hyperplasia, salt-wasting type", "B. Addison disease", "C. Renal tubular acidosis", "D. Pyloric stenosis"],
        ans: "A",
        exp: "21-hydroxylase deficiency (most common CAH, ~95%) presents in males as adrenal crisis with hyponatremia, hyperkalemia, and shock in the first weeks of life. Cortisol and aldosterone are deficient; androgens are excess. 17-OHP is the diagnostic marker. Girls present with virilization (ambiguous genitalia) at birth. Rx: hydrocortisone + fludrocortisone. [Harriet Lane Handbook 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 10-year-old girl presents with 3-week history of polyuria, polydipsia, weight loss, and fatigue. Blood glucose is 420 mg/dL and urine shows ketones 3+. Blood pH is 7.25. What is the diagnosis?",
        opts: ["A. Type 2 diabetes mellitus", "B. Diabetes insipidus", "C. Diabetic ketoacidosis in Type 1 DM", "D. Hyperglycemic hyperosmolar state"],
        ans: "C",
        exp: "DKA in Type 1 DM: glucose >200, pH <7.3, bicarbonate <15, ketonemia/ketonuria. Type 1 DM is autoimmune (anti-GAD, anti-islet antibodies). DKA is the most common presentation in newly diagnosed pediatric T1DM. Rx: IV fluid resuscitation + insulin infusion + K replacement. HHS occurs in T2DM (minimal ketosis, higher glucose). [Harriet Lane Handbook 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "An 8-year-old boy presents with pubic hair and testicular enlargement (>4 mL). Bone age is advanced. What is the FIRST investigation to order?",
        opts: ["A. Serum testosterone", "B. MRI of the brain", "C. GnRH stimulation test", "D. Karyotype"],
        ans: "B",
        exp: "Precocious puberty in boys (onset <9 yrs) is almost always due to an organic/CNS cause (hamartoma, glioma, craniopharyngioma). MRI brain is mandatory for all boys with precocious puberty to rule out a CNS tumor. GnRH stimulation test confirms central precocious puberty (LH response >5 IU/L). Treatment: GnRH agonist. [Harriet Lane Handbook 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 4-year-old child presents with excessive thirst, polyuria (urine output >5 L/day), and dilute urine (specific gravity 1.001). Serum sodium is 155 mEq/L. After water deprivation, urine osmolality fails to rise. DDAVP administration causes urine to concentrate. What is the diagnosis?",
        opts: ["A. Psychogenic polydipsia", "B. Nephrogenic diabetes insipidus", "C. Central diabetes insipidus", "D. SIADH"],
        ans: "C",
        exp: "Central DI: ADH (vasopressin) deficiency. Water deprivation test: urine fails to concentrate. DDAVP (synthetic ADH) response = concentrates urine → confirms central DI. Nephrogenic DI: kidneys don't respond to ADH, so DDAVP also fails. Psychogenic polydipsia: urine concentrates with water deprivation. Rx for central DI: intranasal DDAVP. [Harriet Lane Handbook 23e]",
        pareto: "★★ TIER 2"
      },
      {
        q: "A 14-year-old girl has short stature (height age = 10 years), delayed bone age, bradycardia, constipation, and cold intolerance. TSH = 45 mIU/L, T4 = low. TPO antibodies positive. What is the most likely diagnosis?",
        opts: ["A. Congenital hypothyroidism", "B. Hashimoto thyroiditis", "C. Riedel thyroiditis", "D. Subacute thyroiditis"],
        ans: "B",
        exp: "Hashimoto thyroiditis (autoimmune) is the most common cause of acquired hypothyroidism in children and adolescents. It is characterized by elevated TSH, low T4, positive TPO antibodies, and a painless goiter. It predominantly affects females. Growth retardation and delayed puberty may occur. Rx: levothyroxine. [Harrison's 22e + Harriet Lane 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 7-year-old boy is evaluated for short stature. GH stimulation test shows peak GH of 3 ng/mL (normal >10). He has a micropenis, delayed bone age, and low IGF-1. What is the treatment?",
        opts: ["A. Testosterone injections", "B. Recombinant human growth hormone (rhGH)", "C. Anabolic steroids", "D. Zinc supplementation"],
        ans: "B",
        exp: "Growth hormone deficiency (GHD) presents with short stature, delayed bone age, mid-facial hypoplasia, and micropenis in males. Diagnosis: low IGF-1 + peak GH <10 ng/mL on stimulation testing. Treatment: daily subcutaneous recombinant GH injections until growth plate fusion. [Harriet Lane Handbook 23e]",
        pareto: "★★ TIER 2"
      },
      {
        q: "Which enzyme deficiency is responsible for the MOST COMMON form of congenital adrenal hyperplasia?",
        opts: ["A. 11β-hydroxylase", "B. 3β-hydroxysteroid dehydrogenase", "C. 21-hydroxylase", "D. 17α-hydroxylase"],
        ans: "C",
        exp: "21-hydroxylase deficiency accounts for ~95% of all CAH cases. It blocks the conversion of 17-OHP → 11-deoxycortisol (cortisol pathway) AND progesterone → deoxycorticosterone (aldosterone pathway), causing cortisol/aldosterone deficiency and androgen excess. The buildup of 17-OHP is the diagnostic marker. [Harriet Lane Handbook 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A newborn female has ambiguous genitalia. The karyotype is 46,XX. Serum 17-hydroxyprogesterone is elevated. What is the most likely diagnosis?",
        opts: ["A. Turner syndrome", "B. Androgen insensitivity syndrome", "C. Congenital adrenal hyperplasia (21-hydroxylase deficiency)", "D. True hermaphroditism"],
        ans: "C",
        exp: "A 46,XX female with elevated 17-OHP and ambiguous genitalia (virilized external genitalia due to androgen excess) is the classic presentation of 21-hydroxylase deficiency CAH. Androgen insensitivity = 46,XY with female phenotype. Turner = 45,X, female phenotype with streak gonads. [Harriet Lane Handbook 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "In managing a child with newly diagnosed type 1 DM and DKA, what is the most dangerous complication to monitor for during IV fluid and insulin therapy?",
        opts: ["A. Hypoglycemia", "B. Cerebral edema", "C. Hyperkalemia", "D. Thrombosis"],
        ans: "B",
        exp: "Cerebral edema is the most dangerous complication of DKA treatment in children, with mortality up to 90% if untreated. It occurs 4–12 hours into treatment, likely due to rapid fluid shifts. Warning signs: headache, altered mental status, bradycardia, hypertension. Rx: IV mannitol or hypertonic saline immediately. [Harriet Lane Handbook 23e]",
        pareto: "★★★ TIER 1"
      }
    ]
  },
  {
    name: "TOPIC 3: RESPIRATORY SYSTEM",
    color: "1E5945",
    pareto: "HIGH YIELD (Pareto Tier 1 — 80% exam weight)",
    feynman: {
      coreIdea: "Pediatric respiratory disease follows age. Ask yourself: how old is the child? A 6-month-old with wheeze = bronchiolitis (RSV). A 2-year-old with barking cough = croup. A school-age child with recurrent wheeze = asthma. A teen with chronic productive cough + failure to thrive = cystic fibrosis. Age is your first diagnostic tool.",
      highYield: [
        "Croup (Laryngotracheobronchitis): Parainfluenza virus, 6 months–3 years, barking ('seal-like') cough, stridor, steeple sign on X-ray. Rx: Nebulized epinephrine + oral/IM dexamethasone.",
        "Bronchiolitis: RSV (most common), <2 years, wheezing + tachypnea, bilateral hyperinflation on CXR. Rx: Supportive (oxygen, hydration). No bronchodilators/steroids in typical cases.",
        "Asthma: Reversible airway obstruction, eosinophilic inflammation. Triggers: allergens, exercise, viral URTI. PEFR monitoring. Acute attack: salbutamol (SABA) → IV Mg sulphate → intubation. Chronic: ICS ± LABA.",
        "Pneumonia in children: <5 years: RSV, Strep pneumoniae. >5 years: Mycoplasma pneumoniae (atypical/walking pneumonia). CXR: lobar consolidation (bacterial) vs. bilateral interstitial (viral). Rx: Amoxicillin (bacterial) / Azithromycin (Mycoplasma).",
        "Epiglottitis: H. influenzae type b (unvaccinated), 'thumb sign' on lateral neck X-ray, drooling, high fever, tripod position. EMERGENCY — do NOT examine throat. Rx: Secure airway + IV Cefotaxime.",
        "Cystic fibrosis: CFTR mutation (ΔF508 most common), pancreatic insufficiency + recurrent lung infections (Pseudomonas). Sweat chloride >60 mEq/L diagnostic. Rx: Chest physio, DNase, CFTR modulators (Ivacaftor).",
        "Foreign body aspiration: Right main bronchus most common (more vertical). CXR: obstructive emphysema or atelectasis. Rx: Rigid bronchoscopy.",
        "Pneumothorax: spontaneous (tall thin males, Marfan) or secondary. Tracheal deviation AWAY from affected side. Rx: needle decompression 2nd ICS MCL.",
        "Pulse oximetry: SpO2 <95% requires supplemental O2 in children. <90% = severe hypoxia.",
        "Whooping cough (Pertussis): Bordetella pertussis. Catarrhal → paroxysmal (whoop) → convalescent. Rx: Azithromycin."
      ]
    },
    questions: [
      {
        q: "A 2-year-old presents with sudden onset of barking cough, stridor, and low-grade fever after a 2-day URI. Neck X-ray shows a 'steeple sign'. What is the most likely diagnosis and causative organism?",
        opts: ["A. Epiglottitis — Haemophilus influenzae", "B. Croup — Parainfluenza virus", "C. Bacterial tracheitis — Staphylococcus aureus", "D. Foreign body aspiration"],
        ans: "B",
        exp: "Croup (laryngotracheobronchitis) is caused by Parainfluenza virus (types 1 and 2), affects children 6 months–3 years, and causes the classic barking/seal-like cough with inspiratory stridor. The steeple sign on AP neck X-ray reflects subglottic narrowing. Rx: single-dose dexamethasone (0.6 mg/kg PO/IM) ± nebulized racemic epinephrine. [Harriet Lane Handbook 23e + Tintinalli's EM]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 6-week-old infant presents in winter with 3 days of rhinorrhea, progressive wheezing, and feeding difficulty. O2 saturation is 91%. CXR shows bilateral hyperinflation. What is the BEST management?",
        opts: ["A. Oral salbutamol", "B. IV corticosteroids", "C. Supportive care with oxygen and nasogastric feeding", "D. Inhaled budesonide"],
        ans: "C",
        exp: "Bronchiolitis (RSV, most common) in infants <2 years is managed SUPPORTIVELY — oxygen (target SpO2 ≥94%), adequate hydration (NG feeds if needed), and monitoring. AAP guidelines do NOT recommend routine bronchodilators, steroids, or antibiotics. High-flow nasal cannula (HFNC) may be used if SpO2 remains low. [Harriet Lane Handbook 23e + AAP Guidelines]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 5-year-old with known asthma presents with acute severe wheeze, accessory muscle use, and PEFR 40% of predicted. He receives 3 salbutamol nebulizations with minimal improvement. What is the NEXT best step?",
        opts: ["A. IV aminophylline", "B. IV magnesium sulphate", "C. Oral prednisolone and discharge", "D. Leukotriene receptor antagonist"],
        ans: "B",
        exp: "In acute severe asthma not responding to initial bronchodilators (SABA), IV magnesium sulphate (25–40 mg/kg) is the next step. It works by relaxing smooth muscle through calcium antagonism. PEFR <50% = severe; <33% = life-threatening. Aminophylline is now less preferred due to side effects. Systemic corticosteroids should also be given. [Harriet Lane Handbook 23e + GINA guidelines]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 3-year-old unvaccinated child develops high fever, severe sore throat, drooling, and refuses to lie down. The child appears anxious and in a 'tripod position.' What should you do FIRST?",
        opts: ["A. Examine the throat with a tongue depressor", "B. Take lateral neck X-ray", "C. Secure the airway and call anesthesia", "D. Give oral Amoxicillin"],
        ans: "C",
        exp: "Epiglottitis is a medical emergency caused by H. influenzae type b (in unvaccinated children). The child sits in a tripod/sniffing position. Examining the throat can trigger complete airway obstruction. PRIORITY = secure airway (intubation in OR with ENT/anesthesia on standby), then IV cefotaxime. Lateral neck X-ray shows thumb sign but should not delay airway management. [Tintinalli's EM + Harriet Lane 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 7-year-old presents with recurrent respiratory infections, steatorrhea, and failure to thrive. Sweat chloride test result is 70 mEq/L. What is the most likely diagnosis?",
        opts: ["A. Primary ciliary dyskinesia", "B. Cystic fibrosis", "C. Alpha-1 antitrypsin deficiency", "D. Immunodeficiency"],
        ans: "B",
        exp: "Cystic fibrosis (CF): Autosomal recessive CFTR mutation (ΔF508 most common). Sweat chloride >60 mEq/L is diagnostic. Features: recurrent pulmonary infections (P. aeruginosa late), pancreatic exocrine insufficiency (steatorrhea), failure to thrive, meconium ileus at birth. Rx: Chest physiotherapy, pancreatic enzymes, CFTR modulators (Elexacaftor-tezacaftor-ivacaftor). [Harriet Lane 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 1-year-old child is brought in after suddenly choking while eating peanuts. He is now wheezing. CXR shows unilateral hyperinflation on the right. What is the management?",
        opts: ["A. Heimlich maneuver", "B. Back blows", "C. Rigid bronchoscopy", "D. CT chest and observation"],
        ans: "C",
        exp: "Foreign body aspiration: Right main bronchus (more vertical and wider) is most commonly affected. Partial obstruction → air trapping → unilateral hyperinflation ('obstructive emphysema'). Total obstruction → atelectasis. Rigid bronchoscopy under GA is the definitive treatment and diagnosis. Heimlich is for immediate life-threatening obstruction. [Harriet Lane 23e + Cummings Otolaryngology]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 6-month-old presents in January with first episode of wheeze, cough, and difficulty feeding. On auscultation: diffuse crackles and expiratory wheeze. CXR: hyperinflation. What is the CAUSATIVE organism?",
        opts: ["A. Streptococcus pneumoniae", "B. Respiratory syncytial virus (RSV)", "C. Parainfluenza virus", "D. Rhinovirus"],
        ans: "B",
        exp: "RSV (Respiratory Syncytial Virus) is the most common cause of bronchiolitis, peaking in winter/early spring. It affects infants <2 years, causing first-time wheeze, cough, difficulty feeding, and bilateral crackles/wheeze on examination. High-risk infants (prematurity, CHD) may receive Palivizumab prophylaxis. [Harriet Lane 23e + Fishman's Pulmonary Diseases]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "An 8-year-old girl is prescribed inhaled corticosteroids (ICS) for persistent asthma. What is the MOST important side effect of long-term high-dose ICS in children?",
        opts: ["A. Cataracts", "B. Growth suppression", "C. Adrenal crisis", "D. Cushing syndrome"],
        ans: "B",
        exp: "The most clinically important side effect of long-term high-dose inhaled corticosteroids in children is growth suppression (reduced linear growth velocity). This is dose-dependent and more significant with higher doses. Systemic effects are less than oral steroids but still present. Cataracts and adrenal suppression occur but are less common. [Harriet Lane 23e + GINA]",
        pareto: "★★ TIER 2"
      },
      {
        q: "A 10-year-old presents with 6 weeks of paroxysmal cough followed by a whooping sound during inspiration. He is afebrile. What is the antibiotic of choice?",
        opts: ["A. Amoxicillin-clavulanate", "B. Azithromycin", "C. Ciprofloxacin", "D. Chloramphenicol"],
        ans: "B",
        exp: "Pertussis (Bordetella pertussis): Catarrhal (1–2 weeks, most contagious) → Paroxysmal (2–4 weeks, inspiratory whoop) → Convalescent. Treatment: Azithromycin (drug of choice in children) or Erythromycin. Azithromycin is preferred for infants <1 month due to risk of pyloric stenosis with erythromycin. Post-exposure prophylaxis for close contacts. [Harriet Lane 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 6-year-old has recurrent pneumonia always in the right lower lobe. What investigation is most appropriate?",
        opts: ["A. Sweat chloride test", "B. Chest CT with bronchoscopy", "C. Immunoglobulin levels", "D. Lung biopsy"],
        ans: "B",
        exp: "Recurrent pneumonia in the SAME lobe in a child suggests an anatomic obstruction or local defect — most likely a foreign body, bronchial stenosis, or congenital lung malformation. Chest CT defines anatomy; bronchoscopy diagnoses and treats obstruction. Sweat chloride tests for CF (bilateral, not lobar-specific). Immunoglobulins test for generalized immunodeficiency (typically bilateral). [Harriet Lane 23e]",
        pareto: "★★ TIER 2"
      }
    ]
  },
  {
    name: "TOPIC 4: NUTRITION",
    color: "4A235A",
    pareto: "MEDIUM YIELD (Pareto Tier 1–2 — 70% exam weight)",
    feynman: {
      coreIdea: "Pediatric nutrition is about fueling a rapidly growing body. A newborn doubles birth weight by 5 months and triples by 1 year. Any nutritional deficiency has amplified consequences in children because it interrupts a critical developmental window. Think: which nutrient is missing → what is the clinical consequence → what is the reversal?",
      highYield: [
        "Breastfeeding: WHO recommends exclusive breastfeeding for 6 months, then complementary foods up to 2 years. Breast milk is best — provides IgA, lactoferrin, anti-infective factors. Contraindications: HIV (in resource-rich settings), galactosemia, maternal TB (untreated).",
        "Kwashiorkor: Protein deficiency with adequate calories. Features: edema, ascites, pot belly, skin/hair changes (flag sign), fatty liver, no muscle wasting, good mood until end-stage. Lab: albumin ↓↓.",
        "Marasmus: Overall calorie deficiency. Features: severe wasting (skin and bones), no edema, wrinkled skin, alert, hungry, old man face. Both arms thin (MUAC <11.5 cm = severe).",
        "Vitamin D deficiency (Rickets): Inadequate sunlight/dietary VitD. Features: bowed legs (genu varum), rachitic rosary (costochondral junction), Harrison's groove, craniotabes (skull). Lab: ALP ↑↑, Ca ↓, PO4 ↓, PTH ↑. X-ray: cupping and fraying of metaphyses. Rx: Vitamin D + Calcium.",
        "Vitamin A deficiency: Most common cause of preventable blindness. Night blindness (first symptom), Bitot's spots, xerophthalmia, keratomalacia. Rx: High-dose Vitamin A.",
        "Iron deficiency anemia (IDA): Most common nutritional deficiency worldwide. Hypochromic microcytic anemia. Causes in children: inadequate intake (cow's milk excess), poor diet. Rx: Elemental iron 3–6 mg/kg/day.",
        "Vitamin C (Scurvy): Bleeding gums, perifollicular hemorrhages, corkscrew hairs, subperiosteal bleeding (painful limb swelling), Frankel sign on X-ray. Rx: Ascorbic acid.",
        "Zinc deficiency: Acrodermatitis enteropathica (perioral/perianal rash), growth retardation, diarrhea, hypogonadism, poor wound healing.",
        "Iodine deficiency: Most common preventable cause of hypothyroidism worldwide. Goiter, cretinism (if in utero). Rx: Iodized salt.",
        "Feeding in preterm: Start enteral feeds early (even trophic feeds). Fortified breast milk preferred. Parenteral nutrition if unable to tolerate enteral."
      ]
    },
    questions: [
      {
        q: "A 2-year-old boy from a rural area presents with bilateral leg edema, skin lesions with peeling, and reddish discoloration of hair. His diet consists mainly of maize. Serum albumin is 1.8 g/dL. What is the diagnosis?",
        opts: ["A. Marasmus", "B. Kwashiorkor", "C. Vitamin A deficiency", "D. Pellagra"],
        ans: "B",
        exp: "Kwashiorkor is protein deficiency with adequate caloric intake. Classic features: bilateral pitting edema (hallmark), hypoalbuminemia, 'flaky paint' skin desquamation, flag sign in hair (alternating light/dark bands), and fatty liver. The child appears well-nourished due to edema masking wasting. Maize-based diet lacks protein. Albumin <2 g/dL confirms protein deficiency. [Goldman-Cecil Medicine + Harriet Lane 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 3-year-old presents with bilateral bowed legs, a 'beaded' appearance along the anterior chest wall, and a horizontal groove at the lower ribs. X-ray of wrists shows cupping and fraying of metaphyses. What is the most likely diagnosis?",
        opts: ["A. Scurvy", "B. Rickets", "C. Achondroplasia", "D. Osteomalacia"],
        ans: "B",
        exp: "Nutritional rickets (Vitamin D deficiency): Rachitic rosary (costochondral beading), Harrison's groove (indentation at lower rib/diaphragm attachment), genu varum (bowed legs), craniotabes. X-ray: cupping, fraying, and widening of metaphyses. Labs: ↓Ca, ↓PO4, ↑ALP, ↑PTH, ↓25-OH Vitamin D. Rx: Vitamin D (cholecalciferol) + Calcium supplementation. [Harriet Lane 23e + Goldman-Cecil]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 4-year-old child is brought with complaints of poor night vision and dry, dull corneas. On examination, small triangular foamy patches are seen lateral to the cornea on both eyes. What is the diagnosis?",
        opts: ["A. Vitamin B2 deficiency", "B. Glaucoma", "C. Vitamin A deficiency with Bitot's spots", "D. Trachoma"],
        ans: "C",
        exp: "Vitamin A (retinol) deficiency is the most common cause of preventable childhood blindness. Stages: Night blindness (earliest) → Conjunctival xerosis → Bitot's spots (triangular foamy patches on bulbar conjunctiva, lateral to cornea) → Corneal xerosis → Keratomalacia (liquefaction) → Blindness. Rx: High-dose Vitamin A (200,000 IU for children >1 year). [Goldman-Cecil + Harriet Lane 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 14-month-old exclusively breastfed infant has Hb 7.2 g/dL, MCV 62 fL, low serum ferritin, and low serum iron with high TIBC. What is the most likely cause of anemia?",
        opts: ["A. Thalassemia", "B. Iron deficiency anemia", "C. Vitamin B12 deficiency", "D. Hemolytic anemia"],
        ans: "B",
        exp: "Iron deficiency anemia (IDA): most common nutritional deficiency in children. Hypochromic microcytic (low MCV) anemia. Breastfed infants after 6 months need iron supplementation as breast milk is low in iron. Cow's milk excess also reduces iron absorption. TIBC ↑, serum iron ↓, ferritin ↓, reticulocyte count ↓. Rx: Elemental iron 3–6 mg/kg/day for 3 months. [Harriet Lane 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 5-year-old presents with painful swelling of the legs, bleeding gums, and perifollicular hemorrhages around hair follicles. The child had been on a diet lacking fresh fruits and vegetables. What is the deficiency?",
        opts: ["A. Vitamin K", "B. Vitamin C (Ascorbic acid)", "C. Vitamin D", "D. Zinc"],
        ans: "B",
        exp: "Scurvy (Vitamin C deficiency): Ascorbic acid is needed for collagen synthesis. Features: bleeding gums, perifollicular/subperiosteal hemorrhages, corkscrew hairs, Frankel sign (zone of provisional calcification on X-ray), painful extremities (pseudoparalysis). Subperiosteal hematoma in children mimics child abuse. Rx: Vitamin C 100–300 mg/day. [Goldman-Cecil + Harriet Lane 23e]",
        pareto: "★★ TIER 2"
      },
      {
        q: "According to WHO recommendations, when should complementary feeding be introduced in a normally growing exclusively breastfed infant?",
        opts: ["A. 3 months", "B. 4 months", "C. 6 months", "D. 9 months"],
        ans: "C",
        exp: "WHO recommends exclusive breastfeeding for the FIRST 6 months, then introduction of complementary foods while continuing breastfeeding up to 2 years or beyond. Introducing solids before 4 months increases allergy risk; delaying beyond 6 months risks iron/zinc deficiency and developmental lag. [WHO + AAP + Harriet Lane 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A child presents with a perioral and perianal rash, chronic diarrhea, and growth failure. There is a history of exclusive breastfeeding beyond 1 year with no supplementation. Plasma zinc is very low. What is the diagnosis?",
        opts: ["A. Celiac disease", "B. Acrodermatitis enteropathica (Zinc deficiency)", "C. Inflammatory bowel disease", "D. Biotin deficiency"],
        ans: "B",
        exp: "Acrodermatitis enteropathica is the clinical manifestation of severe zinc deficiency (inherited or acquired). It presents with the triad: perioral/perianal/acral dermatitis, diarrhea, and alopecia. Zinc is essential for >300 metalloenzymes. Acquired form in breastfed infants after 6 months (low breast milk zinc). Rx: Zinc supplementation 1–3 mg/kg/day. [Harriet Lane 23e + Goldman-Cecil]",
        pareto: "★★ TIER 2"
      },
      {
        q: "A child in a mountainous region presents with enlarged thyroid gland and features of hypothyroidism. Mother also has a goiter. What is the most likely cause of the mother's and child's condition?",
        opts: ["A. Hashimoto thyroiditis", "B. Iodine deficiency", "C. Graves disease", "D. Subacute thyroiditis"],
        ans: "B",
        exp: "Iodine deficiency is the most common cause of preventable hypothyroidism worldwide, particularly in mountainous/landlocked regions. Causes endemic goiter and cretinism (intellectual disability, deafness, hypothyroidism) when deficiency occurs in utero. Prevention: iodized salt. Diagnosis: low urinary iodine. [Harriet Lane 23e + Goldman-Cecil]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A severely malnourished 18-month-old child with marasmus is admitted for treatment. Which of the following is the MOST dangerous early complication to watch for when starting refeeding?",
        opts: ["A. Refeeding syndrome (hypophosphatemia)", "B. Diarrhea", "C. Hyperglycemia", "D. Hypernatremia"],
        ans: "A",
        exp: "Refeeding syndrome: Occurs when severely malnourished patients receive rapid nutritional rehabilitation. As cells take up glucose (+ insulin spike), phosphate, potassium, and magnesium shift intracellularly causing life-threatening hypophosphatemia, hypokalemia, hypomagnesemia → cardiac arrhythmias, respiratory failure, seizures. Rx: Slow, cautious refeeding; monitor and supplement electrolytes. [WHO SAM Guidelines + Harriet Lane 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A premature infant at 28 weeks gestation is unable to tolerate full enteral feeds. What is the preferred nutritional support?",
        opts: ["A. Undiluted cow's milk formula", "B. Parenteral nutrition + trophic enteral feeds", "C. Wait until 34 weeks to start feeding", "D. Full caloric enteral feeding from day 1"],
        ans: "B",
        exp: "In premature infants unable to tolerate full enteral feeds, parenteral nutrition (PN) provides macronutrients and micronutrients IV while trophic (minimal enteral) feeds are started early to stimulate gut maturation and prevent mucosal atrophy. Fortified human milk is preferred when possible. Waiting delays nutrition and increases complication risk. [Harriet Lane 23e + AAP Guidelines]",
        pareto: "★★ TIER 2"
      }
    ]
  },
  {
    name: "TOPIC 5: GROWTH AND DEVELOPMENT",
    color: "2C3E50",
    pareto: "HIGH YIELD (Pareto Tier 1 — 80% exam weight)",
    feynman: {
      coreIdea: "Development is not random — it follows a predictable order: cephalocaudal (head before feet), proximal-to-distal (trunk before fingers), and gross before fine motor. Think of developmental milestones as a flight checklist — each milestone must be cleared before takeoff to the next stage. A 'red flag' is a missed milestone that signals the plane might not fly.",
      highYield: [
        "Birth weight: average 3–3.5 kg. Loses 10% first week, regained by 10–14 days. Doubles by 5 months, triples by 1 year, quadruples by 2 years.",
        "Height/Length: Birth = ~50 cm. +25 cm in year 1. +12 cm in year 2. +6 cm/year until puberty. Adult height = 2× height at age 2.",
        "Head circumference: Birth = 34–35 cm. Grows 2 cm/month for first 3 months, 1 cm/month for next 3 months, 0.5 cm/month for months 7–12. Adult HC = 55 cm.",
        "Anterior fontanelle: Closes at 9–18 months. Posterior fontanelle: closes at 6–8 weeks.",
        "Gross motor milestones: 3 months = head control. 6 months = sits with support. 9 months = stands with support. 12 months = walks alone. 18 months = runs. 2 years = stairs (two feet per step). 3 years = tricycle. 4 years = hops. 5 years = skips.",
        "Fine motor: 3–4 months = reaches for objects. 6 months = palmar grasp. 9 months = pincer grasp (index-thumb). 12 months = 2-block tower. 18 months = scribble. 2 years = 6-block tower. 3 years = copies circle. 4 years = copies cross. 5 years = copies triangle.",
        "Language: 2 months = cooing. 6 months = babbling. 12 months = 1–3 words with meaning (Mama, Dada). 18 months = 10 words. 2 years = 50 words + 2-word sentences. 3 years = 3-word sentences, 75% intelligible.",
        "Red flags: No social smile by 3 months. No babbling by 12 months. No single words by 16 months. No 2-word phrases by 24 months. Any regression = IMMEDIATE referral.",
        "Puberty: Girls: thelarche (breast budding, 8–13 years) → pubarche → peak height velocity → menarche (~2 years after thelarche). Boys: testicular enlargement (9–14 years) is FIRST sign → pubarche → penile growth → peak height velocity.",
        "Tanner stages: 5 stages for breast, pubic hair, genital development. Tanner II = beginning of puberty."
      ]
    },
    questions: [
      {
        q: "A mother is concerned about her 2-year-old child's weight. The child weighed 3.2 kg at birth. What is the EXPECTED weight at 2 years of age?",
        opts: ["A. 6.4 kg", "B. 9.6 kg", "C. 12.8 kg", "D. 16 kg"],
        ans: "C",
        exp: "Expected weight at 2 years = 4 × birth weight. If birth weight = 3.2 kg → 4 × 3.2 = 12.8 kg. Milestones: doubles by 5 months (6.4 kg), triples by 1 year (9.6 kg), quadruples by 2 years (12.8 kg). This is a HIGH-YIELD calculation in exams! [Harriet Lane Handbook 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 12-month-old child is brought for a routine developmental check. Which of the following is EXPECTED at this age?",
        opts: ["A. Running independently", "B. Speaking 50 meaningful words", "C. Walking independently", "D. Copying a circle"],
        ans: "C",
        exp: "12 months developmental milestones: Gross motor = walks independently (typical range 9–15 months). Language = 1–3 meaningful words (Mama, Dada). Fine motor = 2-block tower, pincer grasp well-established. Social = stranger anxiety, waves bye-bye, plays pat-a-cake. Running comes at 18 months; 50 words at 2 years; circle copy at 3 years. [Harriet Lane Handbook 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 9-month-old baby cannot sit without support and lacks transfer of objects hand-to-hand. The anterior fontanelle is large. What is the MOST important next step?",
        opts: ["A. Reassure the mother", "B. Check thyroid function tests", "C. Skull X-ray", "D. EEG"],
        ans: "B",
        exp: "Sitting with support is expected by 6 months; sitting without support by 9 months. Failure to sit + large anterior fontanelle raises suspicion for congenital hypothyroidism (large fontanelle, hypotonia, developmental delay). Thyroid function tests (TSH + T4) should be checked. Hypothyroidism is one of the most treatable causes of developmental delay. [Harriet Lane Handbook 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "The FIRST sign of puberty in a normal boy is:",
        opts: ["A. Pubic hair growth", "B. Penile enlargement", "C. Testicular enlargement", "D. Voice change"],
        ans: "C",
        exp: "In boys, the FIRST sign of puberty is testicular enlargement (testicular volume >4 mL, or length >2.5 cm), occurring at Tanner Stage II. This is followed by pubic hair → penile growth → peak height velocity (growth spurt) → voice change (later). In contrast, girls' first sign is thelarche (breast budding). Memorize: BOYS = Testes first; GIRLS = Breasts first. [Harriet Lane Handbook 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 3-year-old child speaks in 3-word sentences, can copy a circle, runs well, rides a tricycle, and dresses with help. Which developmental domain shows a RED FLAG?",
        opts: ["A. Language", "B. Fine motor", "C. Gross motor", "D. None — all are age-appropriate"],
        ans: "D",
        exp: "At 3 years, all these are expected: 3-word sentences (language ✓), copies circle (fine motor ✓), rides tricycle + runs (gross motor ✓), dresses with help (adaptive/social ✓). Normal development — no red flags. Common exam trap: 3-word sentences at 3 years (not 2). 2 years = 2-word sentences. [Harriet Lane Handbook 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "When does the anterior fontanelle normally close?",
        opts: ["A. 3–6 months", "B. 6–8 weeks", "C. 9–18 months", "D. 18–24 months"],
        ans: "C",
        exp: "Anterior fontanelle (diamond-shaped): closes at 9–18 months (average 12–14 months). Posterior fontanelle (triangular): closes at 6–8 weeks. Early closure (<3 months) = craniosynostosis. Delayed closure = rickets, hypothyroidism, Down syndrome, hydrocephalus, achondroplasia. [Harriet Lane Handbook 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A child can climb stairs using both feet on each step, can build a 6-block tower, and uses 50 words. What is the child's MOST LIKELY age?",
        opts: ["A. 12 months", "B. 18 months", "C. 2 years", "D. 3 years"],
        ans: "C",
        exp: "2-year milestones: Gross motor = climbs stairs (2 feet per step), runs. Fine motor = 6-block tower, scribbles. Language = 50+ words, 2-word phrases. Social = parallel play, points to body parts. At 18 months: 10 words, 4-block tower. At 3 years: alternates feet on stairs, 3-word sentences. [Harriet Lane Handbook 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "A 6-year-old child is brought in with concerns of short stature. The growth velocity is 3 cm/year (normal: ≥5 cm/year). Bone age is 4 years. Parents are of normal height. TSH is normal. What is the most likely diagnosis?",
        opts: ["A. Constitutional delay of growth and puberty", "B. Familial short stature", "C. Growth hormone deficiency", "D. Turner syndrome"],
        ans: "A",
        exp: "Constitutional delay of growth and puberty (CDGP): most common cause of short stature in boys. Delayed bone age (bone age = height age < chronological age). Normal GH and thyroid. Family history of late puberty often present. Growth velocity is normal for bone age. Child will eventually reach normal adult height. No treatment needed in most cases; GnRH test differentiates from other causes. [Harriet Lane 23e]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "Which of the following is a RED FLAG for autism spectrum disorder (ASD) in a 24-month-old child?",
        opts: ["A. Stranger anxiety", "B. No two-word phrases", "C. Parallel play", "D. Points to objects of interest"],
        ans: "B",
        exp: "ASD red flags (DSM-5 + AAP): No two-word spontaneous phrases by 24 months (or loss of previously acquired language). Other red flags: no babbling by 12 months, no pointing/waving by 12 months, no single words by 16 months, social withdrawal, repetitive behaviors. Parallel play is normal at 2 years. Stranger anxiety is normal at 9 months. [Harriet Lane Handbook 23e + AAP screening guidelines]",
        pareto: "★★★ TIER 1"
      },
      {
        q: "The head circumference of a normal neonate at birth is approximately:",
        opts: ["A. 30 cm", "B. 34–35 cm", "C. 40 cm", "D. 45 cm"],
        ans: "B",
        exp: "Normal neonatal head circumference = 34–35 cm. It grows rapidly: +2 cm/month for first 3 months, +1 cm/month for months 4–6, +0.5 cm/month for months 7–12. At 1 year = ~46 cm. Adult HC = ~55 cm. HC < -2 SD = microcephaly (causes: TORCH, Zika, genetic). HC > +2 SD = macrocephaly (causes: hydrocephalus, SDH, metabolic). [Harriet Lane Handbook 23e]",
        pareto: "★★★ TIER 1"
      }
    ]
  }
];

// ─────────────────────────────────────────────
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  para("  ★★ TIER 2 — Should Know (next 15% of marks). Study after mastering Tier 1.", { bold: true, color: "375623" }),
  para("  ★ TIER 3 — Nice to Know (last 5% of marks). Study only if time permits.", { bold: true, color: "595959" }),
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// QUICK REVISION SUMMARY
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  makeHeading("QUICK REVISION SUMMARY — PARETO TIER 1 ONLY", HeadingLevel.HEADING_1, "C55A11"),
  para("Study THESE in this order for maximum marks in minimum time:"),
  para("NEONATOLOGY: Apgar scoring · RDS/Surfactant · Neonatal jaundice (pathologic vs physiologic) · Neonatal sepsis organisms · NEC (pneumatosis intestinalis) · Delayed cord clamping contraindications · DKA complications", { bold: true }),
  para("ENDOCRINOLOGY: Congenital hypothyroidism (features + screen) · CAH — 21-hydroxylase (17-OHP, salt-wasting) · T1DM/DKA in children · Precocious puberty (brain MRI in boys) · Hashimoto thyroiditis · Cerebral edema in DKA", { bold: true }),
  para("RESPIRATORY: Croup (steeple sign, parainfluenza, dexamethasone) · Bronchiolitis (RSV, supportive only) · Epiglottitis EMERGENCY (airway first) · Asthma — acute severe (Mg sulphate) · CF (sweat chloride >60) · Foreign body aspiration (right bronchus, rigid bronchoscopy) · Pertussis (azithromycin)", { bold: true }),
  para("NUTRITION: Kwashiorkor vs. Marasmus · Rickets (X-ray + labs) · Vitamin A (Bitot's spots) · IDA in children · Scurvy · WHO complementary feeding at 6 months · Refeeding syndrome", { bold: true }),
  para("GROWTH & DEVELOPMENT: Weight milestones (doubles 5m, triples 1yr, quadruples 2yr) · Motor milestones (walk 12m, run 18m) · Language milestones (1 word 12m, 2-word 24m) · Fontanelle closure (anterior 9-18m) · First sign puberty (testes in boys, breasts in girls) · ASD red flags", { bold: true })
);

// BUILD DOC
const doc = new Document({
  creator: "Orris Medical AI",
  title: "MBBS Pediatrics 50 MCQs",
  description: "50 High-Yield Pediatrics MCQs with Pareto Rule and Feynman Technique",
  styles: {
    paragraphStyles: [
      {
        id: "Normal",
        name: "Normal",
        run: { size: 22, font: "Calibri" }
      }
    ]
  },
  sections: [{ children: allSections }]
});

Packer.toBuffer(doc).then(buffer => {
  fs.writeFileSync('/home/daytona/workspace/pediatrics-mcq/Pediatrics_50_MCQs_Pareto_Feynman.docx', buffer);
  console.log("SUCCESS: Document created!");
}).catch(err => {
  console.error("ERROR:", err);
});