Pediatric Lecture Notes Review

Diabetes Mellitus in Children

• Definition: Diabetes Mellitus (DM) is a metabolic disorder of multiple etiologies characterized by chronic hyperglycemia with disturbances of carbohydrate ($CHO$), fat, and protein metabolism resulting from defects of insulin secretion, action, or both.
• Epidemiology: It is the most common endocrine problem in children. In pediatric populations, Type 1 is more common, particularly in children below $5$ years of age. Type 2 is increasingly seen in older children.
• Pathophysiology:
  • Clinical significance develops when $90\%$ of functioning Beta-cells ($\beta\text{-cell}$) have been destroyed, leading to a loss of insulin secretion.
  • Insulin is an anabolic hormone. Its absence creates a catabolic state characterized by decreased glucose utilization and decreased uptake by tissues.
  • There is an increase in glucose catabolic hormones ($\text{glucagon} + \text{epinephrine} + \text{Growth Hormone} + \text{Cortisol}$). These hormones stimulate lipolysis, leading to fatty acid release and ketone body production.
  • Gluconeogenesis is increased, further leading to hyperglycemia.
  • When blood glucose ($BG$) exceeds the renal threshold of $180\,\text{mg/dL}$, it results in glucosuria, leading to osmotic diuresis, increased urine output, and fluid intake (explaining the symptoms of polyuria and polydipsia).
• Classification of DM:
  • Type 1 DM: Characterized by idiopathic or autoimmune $\beta\text{-cell}$ destruction.
  • Type 2 DM: Caused by defects in insulin secretion or insulin action.
  • Other Specific Types: Includes MODY (Maturity-onset diabetes of the young), neonatal DM, Malnutrition DM, Cystic Fibrosis-related DM, and Cushing Syndrome-related ($2^{\text{nd}}$ degree DM).
  • Gestational DM: DM diagnosed during pregnancy.
• Specific Diabetic Profiles:
  • Type 2 DM: Characterized by insulin resistance with relative insulin insufficiency. It is associated with obesity and Acanthosis nigricans. History may show family incidence of obesity, hypertension ($HTN$), or hyperlipidemia. It typically affects older children and adolescents.
  • MODY: There are five classes, with some following an autosomal dominant mode of inheritance. It is not associated with immunologic or genetic markers for Type 1.
  • Transient Neonatal DM: Observed in both term and preterm infants but is more common in preterms. It is caused by the immaturity of Islet $\beta\text{-cells}$. Infants present with prominent polyuria and dehydration but look well and suck vigorously. They are highly sensitive to insulin and the condition usually disappears within $4\text{--}6$ weeks.
  • Type 1 DM: Autoimmune disease triggered by environmental factors in genetically susceptible individuals. Both humoral and cell-mediated immunity are stimulated.
    • Associated Autoimmune Diseases: Addison's disease, Hashimoto's thyroiditis, Coeliac disease, Vitiligo, Pernicious anaemia.
    • Environmental Triggers: Viruses ($\text{Coxsackie B}$, Mumps, Rubella, CMV) and dietary factors (Cow's milk protein, contaminated sea food).
    • Genetic Evidence: Black populations show higher incidence than White. Familial clustering exists. In identical twins, there is a $70\%$ concordance. Specific genetic markers include $HLA$ haplotypes $DR3$ and $DR4$ and $DQ$ molecular markers.
    • Drug/Chemical Triggers: Steroids, Interferon, Pentamidine.
  • Mauriac Syndrome: Characterized by short stature, hepatomegaly, and Cushingoid features.
• Clinical Presentation:
  • Triad: Polyuria, Polydipsia, and weight loss.
  • Diabetic Ketoacidosis ($DKA$) may be the first presentation.
  • Other symptoms: Fatigability, poor school performance, vaginal candidiasis, and secondary nocturnal enuresis.
• Diagnosis:
  • Symptomatic patient with Random Blood Glucose ($RBG$) $> 11.1\,\text{mmol/L}$ ($200\,\text{mg/dL}$) is diagnostic.
  • Fasting Blood Glucose ($FBG$) $> 126\,\text{mg/dL}$ is diagnostic.
  • $HbA1c > 6.5$ is diagnostic.
  • Stress Hyperglycemia: Acute infection in young, non-diabetic children can cause hyperglycemia without ketoacidosis.
• Honeymoon Period: Observed in $50\text{--}60\%$ of newly diagnosed patients. Due to $\beta\text{-cell}$ reserve and initiation of insulin therapy, blood glucose normalizes. This period can last up to one year. Insulin therapy should never be stopped during this time, but the dose needs close adjustment.
• Complications:
  • Acute: $DKA$, hypoglycemia (with coma, seizures, and chronic CNS damage).
  • Late Onset: Retinopathy, Neuropathy, Nephropathy, IHD, and Stroke (often after $5$ years of diagnosis).
  • Growth Retardation: Somatic (weight and height) and sexual (delayed puberty, delayed menarche, undeveloped breasts).
  • Limited Joint Mobility: The "Prayer's sign" due to joint stiffness indicates poor control.
• Insulin Therapy Management:
  • Goals: Eliminate acute symptoms, prevent complications, achieve biochemical control, and maintain growth and development.
  • Elements: Education on diabetes, insulin life-saving skills, meal planning, and sick-day management.
  • Daily Dose: $0.5\text{--}1\,\text{U/kg/day}$ given subcutaneously $30$ minutes before meals.
  • Injection Sites: Abdominal wall (most constant absorption), Deltoids, lateral side of the thigh, and upper quadrant of the buttock. Rotation is vital to avoid lipohypertrophy.
• Types of Insulin:
  • Rapid Acting (Novorapid): Begins within $5\text{--}20$ minutes.
  • Short Acting (Soluble, Regular): Begins within $30$ minutes; duration up to $8$ hours.
  • Intermediate Acting (Isophane/NPH): Begins within $60\text{--}90$ minutes.
  • Mix Insulin (Mixtard): Combination of $30\%$ rapid/short acting and $70\%$ intermediate acting.
  • Long Acting (Lantus): Peak at $8\text{--}14$ hours; duration $24\text{--}36$ hours.
• Insulin Side Effects: Hypoglycemia, lipoatrophy (in which case, insulin is injected around the area), lipohypertrophy (avoid the area), insulin allergy, and insulin antibodies.
• Diet and Activity: Diet must match the insulin regimen, usually $3 meals + 3 snacks$. Children below $4$ years may be put on a free diet. Exercise increases muscle sensitivity to insulin and glucose utilization, potentially precipitating hypoglycemia. Extra snacks should be given before vigorous exercise, and insulin or dietary intake adjusted for prolonged activity.
• Monitoring and Control:
  • Good control: $2\text{-hour}$ postprandial blood glucose $< 200\,\text{mg/dL}$.
  • $HbA1c$ Ranges:
    • $3\text{--}7\%$: Optimum control.
    • $7\text{--}8.5\%$: Good control.
    • $8.5\text{--}9.5\%$: Moderate control.
    • $> 10\%$: Bad control associated with complications.
  • Long-term Monitoring Tests: Thyroid Function Test ($TFT$) at diagnosis and yearly. Microalbuminuria (nephropathy) yearly after age $10$. Annual eye exam and Coeliac screening if symptomatic.
• Phenomena:
  • Somogyi Phenomenon: Early morning hypoglycemia (headache, sweating, tremor) followed by rebound hyperglycemia at $9:00\,\text{AM}$ due to counter-regulatory hormones. Management: Reduce evening insulin dose by $10\%$.
  • Dawn Phenomenon: Early morning hyperglycemia without preceding hypoglycemia, caused by the weaning out of insulin effect and growth hormone surge. Management: Increase evening dose by $10\text{--}15\%$ or delay the evening dose.
  • Differentiation: Check Blood Glucose ($BG$) at $3:00\,\text{AM}$; if low, it is Somogyi; if high, it is Dawn Phenomenon.
• Sick Day Management: Monitor $RBG$ and urine for sugar/acetone every $4\text{--}6$ hours. If $RBG > 250\,\text{mg/dL}$ with acetonuria or $RBG > 300\,\text{mg/dL}$ without acetonuria, give an extra dose of soluble insulin ($10\text{--}20\%$ of total daily dose) and enhance oral intake.

Upper Respiratory Tract Infections

• Anatomy:
  • Upper Tract: Nasal cavity, Pharynx, Larynx.
  • Lower Tract: Trachea, Bronchi, Bronchioles, Alveoli, and Lungs.
• Viral Croup (Acute Laryngotracheobronchitis):
  • Commonly caused by Parainfluenza virus types $1$, $2$, and $3$. Other causes: Adenovirus, Influenza, and RSV.
  • Onset is common in winter, affecting ages $3\,\text{months}$ to $3\,\text{years}$.
  • Signs/Symptoms: Mild fever and a classic triad of Inspiratory stridor, barking cough (dog cough), and hoarseness of voice. Respiratory distress features include agitation, hypoxemia, hypercapnia, tachypnea, and tachycardia.
  • Diagnosis: Clinical presentation and X-ray (narrowing of the trachea column just below the vocal cords, known as the "Steeple sign").
  • Treatment:
    • Mild: Outpatient management with oral steroid syrup (Orazone) for $4$ days.
    • Moderate: Hospital admission, Racemic epinephrine nebulizer ($0.25\text{--}0.5\,\text{mL}$ diluted in $3\text{--}5\,\text{mL}$ of $NS$), and corticosteroids ($0.6\,\text{mg/kg}$).
    • Severe: ICU preparation, early corticosteroids, and epinephrine.
  • Admission Criteria: Suspected epiglottitis, progressive stridor at rest, respiratory distress, cyanosis, pallor, decreased sensorium, or high fever.
• Acute Epiglottitis:
  • Acute, life-threatening infection of supraglottic tissues primarily caused by Haemophilus influenzae type B. Other pathogens: $Strep.\,pyogenes$, $Strep.\,pneumoniae$, $Staph.\,aureus$.
  • Incidence is high in ages $2\text{--}6\,\text{years}$, though decreasing due to vaccination.
  • Presentation: High-grade fever and a triad of inspiratory stridor (sudden onset), respiratory distress, and hot potato voice. The child appears toxic (ill), assumes a tripod position (leaning forward, hyperextended neck, mouth open, drooling saliva), and has dysphagia and restlessness.
  • Diagnosis: Direct laryngoscopy under anesthesia shows a cherry-red, edematous epiglottis. Lateral neck X-ray shows the "Thumbprint sign".
  • Treatment: ICU admission, secure airway with endotracheal intubation, oxygen, and antibiotics (Ceftriaxone $100\,\text{mg/kg/day}$) for $7\text{--}10$ days. Rifampin prophylaxis for close contacts.
  • Contraindications: If suspected, do not examine the throat, use narcotics, attempt venipuncture, or place the patient supine, as these can precipitate cardiorespiratory arrest.

Lower Respiratory Tract Infections

• Bronchiolitis:
  • Inflammatory obstruction (edema and mucus) of the bronchioles, typically viral, leading to gas exchange mismatch (perfusion/ventilation).
  • Viruses: Respiratory Syncytial Virus (RSV) accounts for $50\%$. Also Adenovirus and Parainfluenza $3$. Humans are the only RSV source.
  • Demographics: $90\%$ of cases in infants $1\text{--}9\,\text{months}$ old, occurring in winter/spring.
  • Presentation: Gradual development of cough, shortness of breath ($SOB$), wheezing, and lung hyperinflation.
  • Risks: Crowded conditions, lack of breastfeeding, smoking mothers, male gender. High risk in premature infants or those with cardiac, pulmonary, or neuromuscular disease.
  • Diagnosis: Viral detection in nasopharyngeal secretions by culture/$|PCR. CXR shows hyperinflation of lungs and increased AP diameter.\n * **Treatment**: Humidified O_2$($O_2$saturation check), rehydration (provide$2/3 of maintenance if in distress), and nebulized salbutamol (if effective). Ribavirin or Palivizumab for high-risk infants.\n * **Complications**: Bacteremia, pericarditis, cellulitis, empyema, meningitis, suppurative arthritis. Hypoxia is common; dehydration is the second most common complication.\n * **Differential**: Bronchiolitis is typically in children < 1\,\text{year}$; asthma is typically$> 2\,\text{years}.\n* **Pneumonia**:\n * Inflammation of the lung parenchyma.\n * **Classification**:\n * Morphology: Bronchopneumonia (involves bronchi), Lobar pneumonia (involves parenchyma, bronchi spared), Interstitial pneumonia.\n * Etiology: Congenital or Acquired. Community-acquired (H.\,influenzae$,$Strep.\,pneumoniae$), Hospital-acquired ($MRSA$,$Pseudomonas$,$Klebsiella$), Immunompromised ($Fungi$,$P.\,jirovecii).\n * Complication status: Simple vs. Complicated.\n * **Causes by Age**:\n * 80\%$viral;$20\% bacterial.\n * 1\text{--}28\,\text{days}: Group B Streptococcal.\n * 4\text{--}8\,\text{weeks}$:$Staph.\,aureus.\n * 2\,\text{months } \text{-- } 5\,\text{years}$:$H.\,influenzae\,type\,B.\n * > 5\,\text{years}$:$Streptococcal\,pneumoniae.\n * **Presentation**: High-grade fever (with rigor), cough with sputum (older children), pleuritic chest pain, abdominal pain. Respiratory distress in infants (nasal flaring, cyanosis, retractions).\n * **Physical Exam (Consolidation)**: Decreased movement on affected side, trachea central, increased tactile vocal fremitus, dullness on percussion, bronchial breathing (or diminished if effusion).\n * **Management**: Supportive care (O_2$, hydration, antipyretics). Antibiotics: Amoxicillin/Amoclan/Macrolides for outpatient; Benzyl penicillin/Cefotaxime/Ceftriaxone for inpatient. Vancomycin if$MRSA.\n * **Admission Indications**: Toxic appearance, \%SpO_2 < 92\text{--}94\%$, dehydration, age$< 4\text{--}6\,\text{months}, underlying cardiac/renal/hematological disease.\n * **Complications**: Parapneumonic effusion, lung abscess, Type 2$respiratory failure, pneumothorax, and metastatic infections (endocarditis, meningitis, septic arthritis,$DIC).\n\n# Diabetic Ketoacidosis (DKA)\n\n* **Definition**: A medical emergency characterized by:\n * Hyperglycemia: RBG > 17\,\text{mmol/L}$($300\,\text{mg/dL}).\n * Ketonemia/Ketonuria: Ketone bodies > 5\text{--}7\,\text{mmol/L}.\n * Metabolic Acidosis: pH < 7.3$or$HCO_3 < 15\,\text{mmol/L}.\n * Fluid and electrolyte disturbances.\n* **Pathophysiology**: Lack of insulin prevents glucose utilization. The body uses fat for energy, producing Free Fatty Acids (FFA). Acetyl CoA exceeds liver capacity, leading to ketone body accumulation in the blood. This causes acidosis, dehydration, and potentially cerebral edema or coma.\n* **Precipitating Factors**: Stress (infection, trauma, surgery), inadequate insulin dose, poor adherence (adolescents), and bad education.\n* **Signs/Symptoms**: Dehydration, hyperventilation with acetone smell (acidotic breath), abdominal pain and tenderness with vomiting (mimicking acute abdomen), and disturbed level of consciousness.\n* **Management**:\n * Admission, IV line, oxygen, rotate patient to prevent ulcers.\n * **Rehydration**: If shocked, give 20\,\text{mL/kg}$of$NS$or$RL$as quickly as possible ($20\text{--}30\,\text{mins}). Repeat until circulation restores. This is not subtracted from maintenance.\n * **Maintenance Fluids**: 100\,\text{mL/kg}$for first$10\,\text{kg}$,$50\,\text{mL/kg}$for second$10\,\text{kg}$, and$20\,\text{mL/kg} for every kg thereafter.\n * **Deficit**: Usually assumed to be 10\%$($100\,\text{mL/kg}$). Give maintenance plus half the deficit over the first$24\,\text{hours}.\n * **Fluid Choice**: Initial NS$or$RL$. When blood glucose reaches$14\text{--}17\,\text{mmol/L}$($250\text{--}300\,\text{mg/dL}$), change to$5\%$glucose with$1/2\,NS.\n * **Insulin**: Start 2\,\text{hours}$after hydration. Standard is infusion pump ($0.1\,\text{unit/kg/hr}$). If no pump, give bolus$0.3\,\text{unit/kg}$then$0.1\,\text{unit/kg/hr}$subcutaneously. Titrate to reduce blood glucose by$80\text{--}90\,\text{mg/hr}$. Continue until acidosis clears ($pH > 7.3$or$HCO_3 > 18) and acetonuria disappears.\n * **Potassium**: Total body K^+$is reduced. Initial serum level may be high as insulin deficiency keeps$K^+$in the extracellular fluid ($ECF$). Start$K^+$replacement ($40\,\text{mmol/L}$) after$2\text{--}4\,\text{hours}$or when urine output is established, provided serum$K^+ < 5.5\,\text{mmol/L}.\n * **Acidosis**: Corrects spontaneously with fluids; give NaHCO_3$only if$pH < 7.0.\n* **Monitoring**: Hourly BG$, urine, vitals,$ECG, and neurological checks. Watch for cerebral edema signs (headache, vomiting, bradycardia, behavior change).\n* **Cerebral Edema Management**: Exclude hypoglycemia. Give IV Mannitol (1\,\text{g/kg}$over$20\,\text{mins}$) or$3\,NS$. Reduce IV fluids. Head up$30^{\circ}. CT/MRI.\n\n# Hypoglycemia in Diabetes\n\n* **Definition**: Most common acute complication in Type 1 DM. Can cause permanent CNS impairment.\n* **Thresholds**: Symptoms usually occur below 60\,\text{mg/dL}$in young children or$75\,\text{mg/dL} in older children.\n* **Symptoms**:\n * **Early (Sympathetic)**: Tremor, sweating, palpitation, pallor, blurred vision.\n * **Late (Glycopenic)**: Irritability, drowsiness, convulsions, coma, nightmares.\n* **Grading**:\n * **Mild**: Child aware, self-treats.\n * **Moderate**: Requir help, but oral treatment possible.\n * **Severe**: Requires parenteral therapy.\n* **Treatment**:\n * **Mild/Moderate**: 10\text{--}15\,\text{g}$of glucose/sucrose or$100\,\text{mL}$sweet drink. Follow with complex$CHO meal (fruit/bread).\n * **Severe**: At home, apply honey/jam to oral mucosa; glucagon SC$or$IM$. In hospital,$10\%$dextrose$4\,\text{mL/kg} IV bolus followed by infusion.\n\n# Bronchial Asthma in Children\n\n* **Definition**: Chronic inflammatory process of the airway characterized by reversible airway obstruction and bronchial hypersensitivity to triggers. \n* **Physiology**: Airway inflammation leads to edema, mucus plug formation, and smooth muscle contraction.\n* **Triggers**: Allergens, exercise, viral infection, medications (Aspirin, NSAIDs), smoking.\n* **Presentation**: Recurrent episodes of cough, SOB, and wheezing, often worse at night or after exercise. Physical exam shows dyspnea, barrel-shaped chest, hyper-resonance on percussion, and prolonged expiration with wheeze.\n* **Investigations**: PFTs$show reduced$FEV_1$or$PEFR$by$20\%$. A diagnostic response to bronchodilators is an increase in$FEV_1/PEFR \ge 15\%. CXR shows hyperinflation.\n* **Severity Classification**:\n * **Step 1 (Intermittent)**: Symptoms < 1\text{/week}$.$PEFR \ge 80\%.\n * **Step 2 (Mild Persistent)**: Symptoms > 1\text{/week}$but$< 1\text{/day}$.$PEFR \ge 80\%.\n * **Step 3 (Moderate Persistent)**: Daily attacks affecting activity. PEFR \, 60\text{--}80\%.\n * **Step 4 (Severe Persistent)**: Continuous symptoms, limited physical activity. PEFR < 60\%.\n* **Management (Stepwise)**:\n * Step 1: Short-acting \beta_2$agonist ($SABA) as needed.\n * Step 2: Add inhaled steroid (100\text{--}200\,\mu\text{g}).\n * Step 3: Increase inhaled steroid or add Montelukast (< 5\,\text{years}$); for$> 5\,\text{years}$, add$LABA (Salmeterol).\n * Step 4: High dose inhaled steroids or oral Prednisolone.\n* **Status Asthmaticus (Acute Severe Asthma)**: Asthma not responding to outpatient treatment (3 doses of $SABA$ within 2\,\text{hours}$). Criteria: Silent chest, inability to complete a sentence, tachypnea, cyanosis, impaired consciousness, pulsus paradoxus. Management: ICU admission,$100\%\,O_2$, continuous nebulized salbutamol, IV hydrocortisone ($5\,\text{mg/kg}$every$4\,\text{hours}$), and potentially Magnesium sulfate ($50\text{--}100\,\text{mg/kg}).\n\n# Meningitis\n\n* **Etiology**:\n * **Bacterial**: Serious, causes brain damage, hearing loss, and death.\n * **Viral (Aseptic)**: Typically less severe, resolves with support.\n* **Organisms by Age**:\n * **Neonate**: E.\,coli$, Group B Streptococci,$Listeria\,monocytogenes.\n * **3 months - 5 years**: S.\,pneumoniae$,$N.\,meningitidis$,$H.\,influenzae.\n* **Presentation**:\n * **Neonatal**: Irritability, lethargy, high fever, poor feeding, bulging fontanelle. No obvious meningeal signs.\n * **Infants/Old Children**: Headache, vomiting, photophobia, neck stiffness.\n * **Specific Signs**: Kernig's sign (pain on knee extension with hip flexed), Brudzinski sign (neck flexion causes hip/knee flexion).\n* **Investigations**: Lumbar puncture (LP$) for$CSF analysis. \n * **Bacterial**: Turbid, high pressure, low sugar, high protein, neutrophil-predominant.\n * **Viral**: Clear/colorless, normal sugar, lymphocytes-predominant.\n * **TB**: Straw-colored, low sugar, lymphocytes-predominant.\n * **Contraindications for LP**: Increased intracranial pressure (IICP), infection at site, bleeding tendency, or severe cardiorespiratory disease. \n* **Management**: Supportive (ABC), dexamethasone (0.15\,\text{mg/kg}$every$6\,\text{hours}$given$2\,\text{hours} before antibiotics to reduce cytokine-mediated inflammation), and empirical antibiotics (Ampicillin/Gentamycin for neonates; Benzyl penicillin/Chloramphenicol for older children).\n* **Prophylaxis**: Rifampin for close contacts (H.\,influenzae$:$20\,\text{mg/kg}$;$N.\,meningitidis$:$10\,\text{mg/kg}).\n\n# Acute Rheumatic Fever (ARF)\n\n* **Etiology**: Non-suppurative inflammatory disease involving joints, CNS, skin, and heart, following Group A Beta-hemolytic streptococcal infection (GABS).\n* **Epidemiology**: Common in school age (5\text{--}15\,\text{years}$). Occurs$2\text{--}3\,\text{weeks} after pharyngitis.\n* **Jones Criteria (Major)**:\n * **Polyarthritis**: Migratory, affects large joints, improves with Aspirin, no residual deformity.\n * **Carditis**: Pancarditis (pericardial friction rub, Carey Coombs mid-diastolic murmur, mitral regurgitation pansystolic murmur).\n * **Sydenham's Chorea**: Purposeless, jerky movements, hypotonia. Signs: Milkmaid sign, darting tongue, pronator sign.\n * **Erythema Marginatum**: Red margin outlining patched clear skin on trunk/limbs.\n * **Subcutaneous Nodules**: Hard, painless nodules on extensor surfaces.\n* **Jones Criteria (Minor)**: Fever, arthralgia, prolonged PR interval, raised ESR/CRP, leukocytosis.\n* **Diagnosis**: Evidence of preceding GABS$(elevated ASO titre) +$2$Major OR$1$Major +$2 Minor criteria.\n* **Management**: Penicillin for 10\,\text{days}$to eradicate strep. Aspirin ($100\,\text{mg/kg/day}$) for arthritis. Steroids for carditis. Monthly Benzathine penicillin prophylaxis for secondary prevention ($600,000\,\text{IU}$for$< 7\,\text{years}$;$1.2\,M$for$> 7\,\text{years}).\n\n# Down Syndrome\n\n* **Biology**: Trisomy 21$. Mechanisms: Nondisjunction ($95\%$, maternal age-related), Translocation ($4\%$, some familial), Mosaicism ($1\%, milder).\n* **Features**: Brachycephaly, slanting eyes with epicanthic folds, Brushfield spots, low-set ears, macroglossia/scrotal tongue, Simian crease, and Sandal sign (gap between 1^{\text{st}}$and$2^{\text{nd}} toes).\n* **Associations**: Congenital Heart Disease (50\%$, especially$AVSD$), Duodenal atresia (double bubble sign), acute leukemia ($ALL), hypothyroidism, and early Alzheimer's disease.\n* **Prenatal Screening**: Triple screen test at 15\text{--}20\,\text{weeks} (low AFP, low Estriol, high hCG). Quadruple test includes Inhibin A.\n\n# Nephrotic Syndrome\n\n* **Definition**: Clinical syndrome of Heavy proteinuria (> 2\,\text{g/24hr}$or$> 40\,\text{mg/m}^2\text{/hr}$), hypoproteinemia (albumin$< 2.5\,\text{g/dL}), generalized edema, and hypercholesterolemia.\n* **Minimal Change NS (MCNS)**: Most common (85\text{--}90\%). Normal appearance under light microscope; podocyte foot process shortening under electron microscope. \n* **Management**: Prednisolone (2\,\text{mg/kg/day}$or$60\,\text{mg/m}^2\text{/day}$) for$4\text{--}6\,\text{weeks}$. Relapse is defined as proteinuria$2+$or more for$3$consecutive days. Frequent relapses or steroid resistance may require Cyclophosphamide ($2\text{--}3\,\text{mg/kg/day}$for$2\,\text{months}).\n* **Complications**: Spontaneous bacterial peritonitis (Strept. pneumoniae), thromboembolism, hypovolemic shock, and steroid side effects.\n\n# Malnutrition (PEM)\n\n* **Classification**:\n * **Wellcome**: Based on weight for age and presence of edema.\n * **Marasmus**: Severe wasting, "old man face," no edema, weight < 60\% of expected.\n * **Kwashiorkor**: Edema (pitting, doll-like cheeks), hair changes (Flag sign), dermatosis (flaky paint), fatty liver, weight 60\text{--}80\% of expected.\n* **Management (SAM)**:\n * Appetite test used for outpatient admission.\n * Stabilization Phase (F75 formula) to prevent refeeding syndrome.\n * Catch-up Phase (F100).\n * Treat hypoglycemia (BG < 3\,\text{mmol/L}$), hypothermia, and infection. Use RESONAL for rehydration (high$K^+$, low$Na^+).\n\n# Sickle Cell Disease\n\n* **Genetics**: Autosomal recessive. Substitution of Valine for Glutamic acid at position 6$of the$\beta\text{-globin}$chain ($HbS).\n* **Crises**:\n * **Vaso-occlusive**: Hand-foot syndrome (dactylitis), acute chest syndrome, priapism, stroke.\n * **Sequestration**: Sudden splenic pooling, circulatory collapse.\n * **Aplastic**: Triggered by Parvovirus B19.\n* **Management**: Hydration, analgesia (morphine/diclofenac), hydroxyurea, and folic acid. Exchange transfusion for stroke, acute chest, and priapism.\n\n# Congenital Heart Disease (CHD)\n\n* **Fetal Circulation**: Three shunts (Ductus venosus, Foramen ovale, Ductus arteriosus). Umbilical vein carries oxygenated blood; umbilical arteries carry deoxygenated blood.\n* **Acyanotic CHD**:\n * **VSD**: Most common. Pansystolic murmur at lower left sternal border. Large VSD causes heart failure and pulmonary HTN (Eisenmenger syndrome).\n * **ASD**: Ejection systolic murmur and fixed splitting of S2. \n * **PDA**: Continuous machinery murmur at left infraclavicular area. Wide pulse pressure. Treat with indomethacin in preterms.\n* **Cyanotic CHD (TOF)**:\n * **Tetralogy of Fallot**: Pulmonary stenosis, Overriding aorta, VSD, RVH. Boot-shaped heart on X-ray.\n * **Tet spells**: Paroxysmal hypercyanotic attacks. Management: Knee-chest position, oxygen, morphine, and Propranolol.\n\n# Growth Monitoring\n\n* **Parameters**:\n * **Weight**: Birth (3.5\,\text{kg}$), doubles at$5\,\text{months}$, triples at$1\,\text{year}.\n * **Height**: Birth (50\,\text{cm}$), at 1 year ($75\,\text{cm}).\n * **Head Circumferance**: Birth (33\text{--}35\,\text{cm}$), at 1 year ($45\,\text{cm}).\n * **Bone Age**: Carpal centers appear at 2\,\text{months}$; one additional carpal center for each year until age$6$. Delayed in hypothyroidism; advanced in$CAH.\n\n# Chronic Kidney Disease (CKD)\n\n* **Definition**: GF < 75\,\text{mL/min}$for at least$3\,\text{months}.\n* **Complications**: Growth retardation (renal osteodystrophy), anemia (erythropoietin deficiency), hypertension, and uremic encephalopathy.\n* **Management**: Erythropoietin, phosphate binders (Calcium carbonate), Vitamin D_3, and dialysis/transplantation.\n\n# Bleeding Disorders\n\n* **Haemophilia A**: Factor VIII$deficiency. X-linked recessive. Treatment: Factor$VIII replacement or DDAVP for mild cases.\n* **Haemophilia B**: Factor IX deficiency.\n* **Von Willebrand Disease**: Autosomal dominant. Affects platelet adhesion and carrier of Factor VIII$. Mucosal bleeding, menorrhagia. Prolonged bleeding time and low$vWF levels.\n\n# Malaria\n\n* **Species**: P.\,falciparum$($90\%$in Sudan),$P.\,vivax$,$P.\,ovale$,$P.\,malariae.\n* **Stages of Fever**: Cold (rigors, 15\,\text{mins } \text{-- } 1\,\text{hr}$), Hot (high temp,$1\text{--}4\,\text{hrs}$), Sweating ($1\text{--}4\,\text{hrs}).\n* **Severe Malaria**: Cerebral malaria (impaired consciousness), respiratory distress, circulatory collapse, jaundice, hemoglobinuria (Blackwater fever), hypoglycemia, and severe anemia (Hb < 5\,\text{g/dL}).\n* **Treatment**: Artemether-lumefantrine (AL$) as first-line for uncomplicated; IV Artisunate or IV Quinine for severe malaria. Primaquine for radical cure of$P.\,vivax/ovale$$ (check G6PD first).