Arab Board Pediatrics Part 1 cheat sheet

Fetal hemoglobin (HbF) has higher O2 affinity than adult Hb; P50 ~19 mmHg vs ~27 mmHg, shifting the oxyhemoglobin curve left.

Surfactant is produced by type II pneumocytes from ~24 weeks; phosphatidylglycerol appearance in amniotic fluid indicates lung maturity.

The ductus arteriosus closes functionally within 24-72 h of birth; patency is maintained by high PGE2 and low O2 tension.

GFR at birth is ~20-30 mL/min/1.73 m2 and reaches adult values (~120) by 1-2 years due to increased renal blood flow and filtration surface.

Cystic fibrosis is autosomal recessive, CFTR gene on chromosome 7 (F508del most common); carrier frequency ~1/25 in Caucasians.

Krebs cycle yields 3 NADH, 1 FADH2, and 1 GTP per acetyl-CoA; total ~30-32 ATP per glucose with malate-aspartate shuttle.

Neonatal jaundice physiology: higher RBC mass, shorter RBC lifespan (~70-90 days), immature UDP-glucuronosyltransferase.

The foramen ovale closes functionally at birth with decreased right atrial pressure; anatomical closure by ~1 year in most infants.

Expected weight: doubles birth weight by 4-5 months, triples by 12 months, quadruples by 2 years.

Expected length: increases ~25 cm in year 1, ~12 cm in year 2, then 5-7 cm/year until puberty.

Head circumference: ~35 cm at birth, +12 cm in year 1, +2 cm/year until age 5, then minimal growth.

Mid-parental height: boys = (father + mother + 13)/2 cm; girls = (father + mother − 13)/2 cm (±8.5 cm).

Gross motor milestones: sits unsupported 6-8 mo, pulls to stand 9 mo, walks independently 12-15 mo.

Language milestones: cooing 2 mo, babbling 6 mo, first words 12 mo, 2-word phrases 18-24 mo, 50 words by 2 yr.

Red flags for autism: no babbling by 12 mo, no pointing/gestures by 12 mo, no words by 16 mo, no 2-word phrases by 24 mo.

BMI percentile ≥95th defines obesity; 85th-94th is overweight; <5th warrants failure-to-thrive evaluation.

Apgar scored at 1 and 5 min: HR, respiratory effort, muscle tone, reflex irritability, color; 0-2 each, score ≥7 reassuring.

Surfactant therapy indicated for RDS with FiO2 >0.30-0.40 and signs of respiratory distress; early rescue reduces pneumothorax.

Neonatal sepsis: Group B Streptococcus and E. coli most common; empiric ampicillin + gentamicin.

Physiologic nadir of hematocrit occurs at 8-12 weeks (nadir Hb ~9-11 g/dL); anemia of prematurity occurs earlier and is more severe.

Phototherapy thresholds depend on gestational age, postnatal age, and risk factors; exchange transfusion for very high bilirubin or signs of acute bilirubin encephalopathy.

Necrotizing enterocolitis: feed intolerance, abdominal distension, bloody stools, pneumatosis intestinalis; treat with bowel rest, antibiotics, surgery if perforation.

Hypoxic-ischemic encephalopathy: therapeutic hypothermia (33.5°C for 72 h) within 6 h of birth improves outcomes in moderate-severe cases.

Newborn screening: TSH for congenital hypothyroidism, 17-OHP for CAH, phenylalanine for PKU, hemoglobinopathy screening, hearing screen.

Acyanotic left-to-right shunts: VSD, ASD, PDA; cause pulmonary overcirculation and heart failure, not cyanosis.

Cyanotic lesions with decreased pulmonary flow: Tetralogy of Fallot, tricuspid atresia, pulmonary atresia.

Cyanotic lesions with increased pulmonary flow: TGA, truncus arteriosus, TAPVR, single ventricle.

Tetralogy of Fallot: VSD, overriding aorta, pulmonary stenosis, RV hypertrophy; squatting increases SVR and reduces right-to-left shunt.

Ductal-dependent lesions: TGA, critical coarctation, interrupted aortic arch, severe pulmonary stenosis; start prostaglandin E1 infusion.

Kawasaki disease: fever ≥5 days plus 4 of 5 criteria; IVIG 2 g/kg + aspirin; risk of coronary artery aneurysms.

Innocent murmur features: systolic, soft (≤2/6), no clicks, normal S2, varies with position, no symptoms.

Long QT syndrome: QTc >440-460 ms; risk of torsades; treat with beta-blockers and avoid QT-prolonging drugs.

Asthma: reversible airflow obstruction; stepwise therapy from SABA prn to low-dose ICS, then combination ICS/LABA or LTRA.

Cystic fibrosis diagnosis: sweat chloride ≥60 mmol/L on two occasions, or CFTR mutations plus compatible phenotype.

Croup (laryngotracheobronchitis): barking cough, inspiratory stridor; treat with dexamethasone and nebulized epinephrine for moderate-severe.

Epiglottitis: drooling, tripod positioning, muffled voice; do not inspect throat; secure airway in OR.

Bronchiolitis: most common cause RSV; supportive care; no role for routine bronchodilators, steroids, or antibiotics.

Foreign body aspiration: sudden cough/choking; right mainstem most common; rigid bronchoscopy for removal.

Primary ciliary dyskinesia: situs inversus in ~50%, chronic wet cough, sinusitis, bronchiectasis; low nasal NO.

Pulse oximetry targets in acute asthma: maintain SpO2 ≥92-94%; consider magnesium sulfate for severe exacerbation.

Breast milk provides ~67 kcal/100 mL; term infant needs ~100-120 kcal/kg/day; preterm ~120-150 kcal/kg/day.

Cow milk protein allergy: avoid cow milk protein; extensively hydrolyzed formula first-line, amino acid formula if severe.

Celiac disease: anti-tTG IgA with total IgA; duodenal biopsy shows villous atrophy; lifelong gluten-free diet.

Intussusception: colicky pain, currant-jelly stool, sausage-shaped mass; air enema is diagnostic and therapeutic.

Pyloric stenosis: nonbilious projectile vomiting at 3-6 weeks, hypochloremic hypokalemic metabolic alkalosis; Ramstedt pyloromyotomy.

Hirschsprung disease: failure to pass meconium >48 h, abdominal distension; rectal biopsy shows absent ganglion cells.

Neonatal cholestasis: conjugated bilirubin >1 mg/dL or >20% of total; evaluate for biliary atresia (Kasai before 60 days).

Acute gastroenteritis: ORS 50 mL/kg over 4 h for mild-moderate dehydration; zinc for 10-14 days reduces duration in resource-limited settings.

Nephrotic syndrome: edema, proteinuria >40 mg/m2/h, hypoalbuminemia <2.5 g/dL, hyperlipidemia; most are minimal change disease.

First-line nephrotic therapy: prednisone 60 mg/m2/day for 4-6 weeks then alternate-day; steroid-resistant requires biopsy.

Post-streptococcal glomerulonephritis: cola-colored urine, hypertension, edema 1-2 weeks after pharyngitis; low C3, normalizes in 6-8 weeks.

Hemolytic uremic syndrome: triad of microangiopathic hemolytic anemia, thrombocytopenia, acute kidney injury; often Shiga toxin E. coli.

UTI in infants <2 months: febrile, obtain urine culture, treat parenterally; renal ultrasound for all febrile UTIs <2 years.

Vesicoureteral reflux graded I-V; grade V shows gross dilation and tortuosity; management includes antibiotic prophylaxis for high grades.

Hyponatremia correction: raise Na by ≤8-10 mEq/L in 24 h to avoid osmotic demyelination.

Hyperkalemia in AKI: calcium gluconate for cardiac membrane stabilization, insulin/glucose, salbutamol, then dialysis if refractory.

Congenital hypothyroidism: elevated TSH with low T4; treat with levothyroxine 10-15 mcg/kg/day started within 2 weeks.

Type 1 diabetes: insulin deficiency, ketosis-prone; initial management includes IV fluids, insulin infusion, and potassium replacement.

Diabetic ketoacidosis: avoid rapid fluid boluses; correct deficit over 48 h; monitor for cerebral edema (headache, bradycardia, hypertension).

Congenital adrenal hyperplasia (21-hydroxylase deficiency): salt-wasting, ambiguous genitalia in females, elevated 17-OHP; treat with hydrocortisone and fludrocortisone.

Growth hormone deficiency: short stature, low IGF-1, failed GH stimulation tests; treat with recombinant GH.

Precocious puberty: secondary sexual characteristics before 8 yr (girls) or 9 yr (boys); GnRH agonist for central precocious puberty.

Hypocalcemia in neonates: jitteriness, seizures; treat with IV calcium gluconate; check magnesium.

PKU: phenylalanine hydroxylase deficiency; screen at birth; dietary restriction of phenylalanine with tyrosine supplementation; avoid aspartame.

Iron deficiency anemia: microcytic hypochromic, low ferritin, high TIBC, low MCV; treat with oral iron 3-6 mg/kg/day elemental.

Thalassemia major: chronic transfusion, iron chelation with deferoxamine/deferasirox; monitor ferritin and cardiac iron.

Sickle cell disease: hydroxyurea reduces crises; penicillin prophylaxis until age 5; pneumococcal and meningococcal vaccines.

Acute lymphoblastic leukemia: most common childhood malignancy; peak 2-5 years; treat with multiagent chemotherapy; CNS prophylaxis.

Wilms tumor: abdominal mass, hematuria, hypertension; nephrectomy plus chemotherapy; associated with WAGR, Beckwith-Wiedemann.

Neuroblastoma: median age 2 years; elevated urinary catecholamines (VMA/HVA); opsoclonus-myoclonus may be presenting sign.

Immune thrombocytopenia: isolated thrombocytopenia, petechiae, no lymphadenopathy; IVIG or steroids for significant bleeding.

Hemophilia A: factor VIII deficiency; prolonged aPTT, normal PT; treat with factor replacement; avoid IM injections and aspirin.

Fever without source in infant <3 months: full sepsis workup and empiric antibiotics if ill-appearing or high risk.

Kawasaki disease, MIS-C, and toxic shock syndrome can mimic sepsis; consider in prolonged fever with mucocutaneous findings.

Measles: Koplik spots, maculopapular rash starting at hairline; isolate; vitamin A in severe cases.

Meningococcal disease: petechial/purpuric rash, rapid progression; ceftriaxone plus droplet precautions; chemoprophylaxis for contacts.

Primary immunodeficiency red flags: ≥2 severe infections, failure to thrive, chronic diarrhea, family history, need for IV antibiotics.

SCID: absent thymus, lymphopenia, susceptibility to opportunistic infections; avoid live vaccines; treat with HSCT.

Tuberculosis in children: gastric aspirate for AFB; IGRA may be negative in young children; treat latent TB with isoniazid.

Vaccine schedule: MMR at 12-15 months and 4-6 years; varicella at 12-15 months; HPV at 11-12 years.

Febrile seizures: age 6 months-5 years, generalized, <15 min; simple febrile seizure does not require routine EEG or imaging.

Status epilepticus: benzodiazepine first-line (lorazepam 0.1 mg/kg IV); then phenytoin/fosphenytoin or levetiracetam.

Bacterial meningitis: CSF pleocytosis with neutrophil predominance, low glucose, high protein; treat empirically with ceftriaxone plus vancomycin.

Cerebral palsy: nonprogressive motor impairment; most common cause is prenatal; associated with epilepsy, vision/hearing deficits, intellectual disability.

Hydrocephalus: enlarged head, sunsetting eyes, vomiting; treat with shunt or ETV; monitor for shunt malfunction.

Duchenne muscular dystrophy: X-linked, Gowers sign, calf pseudohypertrophy, elevated CK; treat with steroids and supportive care.

Neonatal seizures: most often subtle; treat with phenobarbital first-line; evaluate for hypoglycemia, hypocalcemia, infection.

Migraine in children: may have bilateral headache, shorter duration; treat with NSAIDs, triptans; consider prophylaxis for frequent attacks.

Well-child visits: newborn, 1, 2, 4, 6, 9, 12, 15, 18, 24 months, then annually; track growth and development.

Routine immunizations per national schedule; catch-up schedules exist for missed doses; live vaccines contraindicated in immunocompromised.

Lead screening: at 9-12 months and 24 months in at-risk children; blood lead ≥5 mcg/dL requires follow-up.

Anemia screening: hemoglobin at 12 months; universal if high risk; treat iron deficiency with oral iron.

Otitis media: amoxicillin first-line for acute otitis media; observation for selected older children with mild disease.

Pharyngitis: group A strep confirmed by rapid antigen or culture; penicillin or amoxicillin for 10 days.

Failure to thrive: weight <5th percentile or crossing two major percentiles; evaluate nutrition, organic causes, psychosocial factors.

Dental care: first dental visit by age 1; fluoride varnish; avoid bottle in bed to prevent early childhood caries.

Pediatric basic life support: 30:2 compression-ventilation for single rescuer, 15:2 for two rescuers; depth one-third AP chest diameter.

Anaphylaxis: IM epinephrine 0.01 mg/kg (max 0.5 mg) of 1:1000 into lateral thigh; repeat every 5-15 min; adjuncts are secondary.

Pediatric assessment triangle: appearance, work of breathing, circulation to skin; used for rapid initial assessment.

Fluid resuscitation in shock: 20 mL/kg isotonic crystalloid bolus; reassess; avoid over-resuscitation in DKA and cardiac disease.

Status epilepticus, hypoglycemia, and head injury are common pediatric emergencies; check glucose in any altered mental status.

Child abuse recognition: unexplained injuries, delay in care, inconsistent history; mandatory reporting to child protection.

Poisoning: activated charcoal within 1 h for select ingestions; naloxone for opioids; specific antidotes for iron, acetaminophen, organophosphates.

Community pediatrics: screen for social determinants (food insecurity, housing, safety); refer to resources; promote injury prevention (car seats, helmets).