6. Pediatric - RS – Miscellaneous 2

Foreign Body Aspiration

  • Foreign body enters the airway, causing difficulty breathing or choking.

  • Peanuts are the most commonly aspirated foreign body.

  • Most common age group: 2-4 years.

  • Foreign body most commonly entrapped in the right bronchus.

  • Symptoms:

    • Choking
    • Cough
    • Shortness of breath
    • Persistent cough followed by bloody cough (or vice versa in AV malformation)
    • Hoarseness of voice
    • Wheezing

  • X-ray findings:

    • Unilateral hyperinflation on expiratory film.

  • Diagnosis: Mainly by history.

  • Management: Rigid bronchoscope (even if X-ray is normal).

Laryngomalacia

  • Congenital weakening of the laryngeal cartilage.
  • Clinical features:
    • Symptoms typically begin within the first 2 months of life and peak at 6-8 months.
    • Inspiratory stridor:
      • Worsens in the supine position.
      • Improves in the prone position.
      • Most common cause of stridor in newborns.
  • Diagnosis: Flexible fiberoptic laryngoscope shows omega sign.
  • Management: Observation, self-limited.

Choanal Atresia

  • A congenital condition characterized by bony and/or membranous obstruction of the posterior nasal passage (choana).
  • Symptoms:
    • Infants are only able to breathe through the mouth.
    • Cyanosis that worsens when feeding and improves when crying.
  • Diagnosis: CT scan of the nasopharynx.

Acute Purulent Sialadenitis

  • Acute inflammation of the salivary glands due to bacterial infection.
  • Etiology: Staphylococcus (most common).
  • Most commonly involves the parotid gland.
  • Signs & symptoms:
    • Unilateral painful swelling and erythema overlying the salivary gland.
    • Usually with purulent discharge expressed from duct orifice.
    • Increased pain at mealtime and elevation of ear lobule.
  • Treatment:
    • Amoxicillin/clavulanate OR clindamycin.
    • Abscess: incision and drainage.

Mumps

  • Inflammation of the salivary glands, particularly the parotid gland.
  • Etiology: Mumps virus.
  • Signs & symptoms:
    • Increased pain at mealtime and elevation of ear lobule.
    • A flat, red rash that begins on the face and disseminates to the rest of the body can occur
  • Complications:
    • Orchitis
    • Encephalitis
    • Meningitis
    • Pancreatitis

Kartagener Syndrome

  • Autosomal recessive disorder characterized by absent or dysmotile cilia caused by a defect in the dynein arm of microtubules.
  • Classic triad:
    • Situs inversus
    • Recurrent sinusitis
    • Bronchiectasis

Causes of Lung Abscess

  • Aerobic:
    • Staph, Strep, Klebsiella, Hemophilus, Pseudomonas, E. coli
  • Anaerobic:
    • Bacteroides, Microaerophilic Strep, Strep. Milleri
    • Candida, Aspergillus
    • E. histolytica

Clubbing

  • Respiratory conditions:
    • Interstitial lung disease
    • Idiopathic pulmonary fibrosis
    • Cystic fibrosis
    • Lung cancer
    • Bronchiectasis
  • Cardiovascular conditions:
    • Cyanotic congenital heart disease
    • Cardiac shunts
  • Infections:
    • Tuberculosis
    • Infections causing lung abscess
  • Hypertrophic osteoarthropathy:
    • A syndrome (either hereditary or paraneoplastic) that manifests with painful nail clubbing, synovial effusions, & periostitis.
  • Cirrhosis
  • IBD
  • Not associated with COPD, asthma

Respiratory Distress Syndrome (RDS)

  • Serious lung condition that causes low blood oxygen.
  • Occurs in pre-term babies.
  • Pathophysiology:
    • Lack of surfactant (decreases the surface tension).
    • Surfactant:
      • Produced by pneumocyte II.
      • Production begins at 28 weeks of gestation.
      • Adequate level reached at 34 weeks of gestation.
      • Function:
        • Decreases alveolar surface tension forces by:
          • Forming a layer between aqueous fluid lining alveoli and air
          • Preventing air/water interface
        • Thus it reduces the lungs’ tendency to recoil & increases lung compliance.
  • Assessment of lung maturity:
    • Lecithin (phosphatidylcholine)–sphingomyelin ratio:
      • Used to screen for lung maturity (adequate surfactant).
      • L : S > 2 indicates lung maturity.
    • Phosphatidylglycerol: Most accurate for lung maturity.
  • Clinical Features:
    • Tachypnea
    • Retractions:
      • Could be subcostal, intercostal, or suprasternal.
    • Grunting:
      • Noisy breathing at the end of expiration.
    • Nasal flaring:
      • When the nostrils become dilated.
    • Recurrent apneas
    • Cyanosis
  • Risk Factors:
    • Premature babies
    • Asphyxia
    • Male babies
    • Cesarean Section
    • Maternal DM
    • Acidosis
    • Hypovolemia, Hypothermia & Hypoxemia
  • CXR:
    • Diagnostic
    • Shows:
      • Ground glass appearance (Reticulonodular)
      • Air bronchograms
  • Management:
    • CPAP
    • Surfactant Administration
    • Oxygen

Meconium Aspiration Syndrome (MAS)

  • Trouble breathing because meconium got into the lungs.
  • Occurs in full term babies.
  • Second most common cause of respiratory distress in the neonatal ICU.
  • Chest X-Ray findings: Patchy infiltrates.
  • Meconium cause: Deactivates the surfactant, causing atelectasis.
  • Complications: Persistent Pulmonary Hypertension of the Newborn (PPHN) → common with MAS, Bacterial pneumonia

Transient Tachypnea of the Newborn (TTN)

  • A respiratory disorder usually seen shortly after delivery in babies who are born near or at term.
  • A self-limited condition.
  • Usually noted in:
    • Larger premature infants
    • Term infants born by precipitous delivery or cesarean section without prior labor.
  • Characterized by tachypnea, mild retractions, hypoxia, and occasional grunting.
  • Usually without signs of severe respiratory distress.
  • Chest radiographs show: Fluid in the lung fissures (typical), Absent air bronchograms and a reticulogranular pattern.

Air Bronchogram

  • Occurs when gas-filled bronchi are visible within an area of lung opacification.
  • Specific Causes:
    • Respiratory distress syndrome
    • Pulmonary Consolidation: Air bronchograms are more commonly seen in consolidation than atelectasis.
    • Pulmonary Edema: Especially with alveolar edema.
    • Non-Obstructive Atelectasis: When gas is expelled due to non-obstructive factors.
    • Severe Interstitial Lung Disease: Such as fibrosis.
    • Neoplasms: Adenocarcinoma or pulmonary lymphoma.
    • Pulmonary Infarct: Due to vascular occlusion.
    • Pulmonary Hemorrhage: Blood fills the airspace.
    • Normal Expiration: In healthy individuals.
    • Persistent Air Bronchograms: If they persist despite appropriate antimicrobial therapy, consider neoplastic processes

Congenital Diaphragmatic Hernia

  • Characterized by protrusion of intra-abdominal contents through an abnormal opening in the diaphragm.
  • Most common type of hernia.
  • Cause BILATERAL pulmonary hypoplasia → no space for the lung to mature.
  • On auscultation, you hear the bowel sound in the chest.

Lower Respiratory Tract Infections (LRTIs)

  • Involve structures below vocal cords (Bronchi, bronchioles & lung).

Bronchiolitis

  • Inflammation & swelling of the bronchioles.
  • Occurs almost exclusively during the first 2 years of life.
  • Etiology: Respiratory Syncytial Virus (RSV) → most common cause.
  • Most frequent mode of transmission: Hand carriage of contaminated secretions.
  • Clinical features:
    • Onset is gradual, with upper respiratory symptoms: rhinorrhea, nasal congestion, fever, & cough.
    • CXR may reveal hyperinflation with air trapping.
    • Respiratory acidosis occurs in sever cases.
    • Apnea is presentation in infants.
  • Diagnosis:
    • Clinical.
    • Definitive diagnosis → by nasopharyngeal aspirate antigen detection by ELIZA.
  • Management:
    • Self limited disease (no need for steroid).
    • Hand decontamination to prevent spread of infection.
    • Contact and large droplets precautions.
    • Hospitalization is indicated for:
      • Respiratory distress
      • Hypoxemia
      • Apnea
      • Dehydration
      • Underlying cardiopulmonary disease
    • Prevention by RSV monoclonal antibody (palivizumab):
      • IM injection, Given as prophylactic at five month
  • Complications:
    • Apnea
    • Respiratory failure
    • Air leak
    • Pneumonia
    • Dehydration
    • Acute Otitis media
    • Sinusitis

Pneumonia

  • Infection & inflammation of the lung parenchyma associated with changes on Chest X-Ray.
  • Etiology: Viruses are the most common cause of pneumonia in all age groups, S. pneumoniae is the most common bacterial pathogen cause pneumonia.
  • Types of pneumonia:
    • Neonates (up to 1 month of age)
      • Congenital → ground glass appearance
      • Group B streptococcus
      • Escherichia coli
      • Listeria monocytogenes
      • CMV
    • 1 – 3 months: Febrile pneumonia
      • Respiratory syncytial virus
      • Parainfluenza viruses
      • Influenza viruses
      • H. influenzae
    • 1 – 3 months: Afebrile pneumonia
      • Chlamydia trachomatis
      • Mycoplasma hominis
      • Ureaplasma
      • Cytomegalovirus
    • 3 month to 5 year
      • Respiratory syncytial virus
      • Parainfluenza viruses
      • Influenza viruses
    • 5 year to 18 year
      • M. pneumoniae
      • Chlamydia pneumonia
  • Lobar pneumonia
    • Presentation:
      • Severe malaise
      • High fever and chills
      • Productive cough with purulent sputum
    • X-ray: Consolidation of an entire lobe of the lung
    • Microorganism: Streptococcus pneumoniae
  • Bronchopneumonia
    • Presentation: Low grade fever, Dry cough
    • X-ray: Patchy consolidation centered around bronchioles
    • Microorganism: Staphylococcus aureus
  • Interstitial (atypical) pneumonia
    • Presentation: Looks Like Commen cold S sing
    • X-ray: Diffuse interstitial infiltrates
    • Microorganism: Mycoplasma pneumoniae
  • Mycoplasma pneumoniae:
    • Children <5 Years with mycoplasma infection present with Upper RTI.
    • Children >5 Years come with LRTI such as pneumonia.
    • Treatment → Macrolide (azithromycin)
    • Younger than 2 years → Respiratory syncytial virus
    • 5 months → Chlamydia trachomatis
    • Mycoplasma pneumoniae → 5 – 15 years
    • Chlamydia trachomatis → 4 – 12 weeks
  • Diagnosis:
    • Physical examination:
    • Laboratory studies:
      • ↑ CRP, ↑ ESR, leukocytosis → in both viral & bacterial pneumonia
      • ↑ Serum ProCalciTonin (PCT): Help to diagnose bacterial lower respiratory tract infections
      • Arterial Blood Gas: ↓ PaO2
  • Indications for hospitalization:
    • High fever (often > 39 °C).
    • Difficulty breathing or cough.
    • Tachypnea
    • Chest indrawing (inferior thoracic wall depresses on inspiration).
    • Cyanosis (lips, oral mucosa, fingernails) or SpO2 < 90%.
    • Nasal flaring.
    • Altered consciousness (abnormally sleepy or difficult to wake).
    • Stridor (hoarse noise on inspiration).
    • Grunting (repetitive noise during expiration).
    • Refusal to drink or feed.

Congenital Pneumonia

  • Pneumonia that becomes clinically evident within 24 hours of birth.
  • X-ray → ground glass appearance

Lung Percussion Findings

  • Resonant: Normal lung
  • Hyper resonant: Pneumothorax
  • Dull: Pulmonary consolidation (increase TVF), Pulmonary collapse, Pulmonary fibrosis
  • Stony Dull: Pleural Effusion (with decrease TVF), Hemothorax

Tuberculosis

  • A bacterial infection caused by Mycobacterium tuberculosis that typically affects the lungs.
  • Clinical features:
  • Chest x-ray:
    • Consolidation (homogeneous with ill-defined borders)
    • Hilar lymphadenopathy (commonly unilateral)
    • Pleural effusion
    • Cavitation (rare)
  • Diagnosis:
    • Sputum samples → first choice
    • Early Gastric aspirate → if could not get sputum
    • Tuberculin Skin Test
  • Treatment by 3 Drugs:
    • Rifampin → body fluid become orange/red in color
    • Isoniazid (INH) → cause B6 deficiency that cause convulsion , give pyridoxine
    • Pyrazinamide
    • Ethambutol (not necessary)
  • Contact management:
    • Positive TST
      • Chest X-ray
        • Normal x-ray → INH
        • Abnormal x-ray → 4 drugs treatment
    • Negative TST with < 8–10 weeks since exposure
      • Children ≥ 5 years of age: no treatment
      • Children < 5 years of age: INH
      • Repeat TST:
        • +ve with normal x-ray → INH
        • +ve with abnormal x-ray → 4 drugs treatment
        • -ve → no treatment
    • Negative TST with > 8–10 weeks since exposure: No further evaluation is required.
  • Adult TB:
    • Infection Source: Reactivation of latent TB infection
    • Symptoms: Chronic cough, Weight loss, Night sweats, Fever, Fatigue
    • Severity: Less
  • Childhood TB
    • Infection Source: Recent transmission
    • Symptoms: Non-specific symptoms, making diagnosis challenging.
    • Severity: More

Respiratory Failure

  • Compensated Respiratory Failure:
    • Breathing: Remains relatively unimpaired
    • Respiratory Rate: Tachypnea (rapid breathing)
    • Intercostal retraction: No
    • Pulse rate: Normal or tachycardia
    • Level of consciousness: Normal
    • PaO2: Normal
    • Management:
      • Oxygen
      • Monitor vitals
      • Elevate the head of the bed to improve lung expansion
      • Non-Invasive Ventilation
      • ABG
      • Avoid Excessive Fluids
      • Avoid Intraosseous Line
  • Decompensated Respiratory Failure:
    • Breathing: Breathing becomes harder (wheezing, coughing)
    • Respiratory Rate:
      • Tachypnea (rapid breathing)
      • Sudden fall in respiratory rate
    • Intercostal retraction: Yes
    • Pulse rate: Bradycardia
    • Level of consciousness:
      • Decreased
      • Exhaustion
      • Decrease activity with parents
    • PaO2: Reduced (<75 mmHg)
    • Management:
      • Oxygen
      • Monitor vitals
      • Invasive Monitoring
      • ABG
      • Fluid Resuscitation (IV or IO)

Pediatric vs Adult Airway

  • Adult Airway:
    • Size: Larger diameter and longer length.
    • Tongue: Relatively smaller in relation to oropharynx.
    • Epiglottis: Stiffer, longer
    • Larynx Position: Located more posteriorly.
    • Larynx Shape: Cylinder-shaped.
    • Narrowest Portion: At the level of the vocal cords.
    • Trachea: Longer and less compliant.
    • Neck: Longer neck.
  • Pediatric Airway:
    • Size: Smaller diameter and shorter length.
    • Tongue: Relatively larger in the oropharynx.
    • Epiglottis: Softer, shorter
    • Larynx Position: Located more anteriorly.
    • Larynx Shape: Funneled-shaped with anterior angulation.
    • Narrowest Portion: At the level of the cricoid cartilage.
    • Trachea: Shorter and highly compliant (risks ‘kinking’).
    • Neck: Shorter neck with a relatively large head.

Upper Respiratory Tract Infections (URTIs)

  • Involve structures at or above the vocal cords.
    • Nasal cavity → rhinitis, common cold
    • Sinuses → sinusitis
    • Pharynx → pharyngitis
    • Middle ear → otitis media
    • Epiglottis → epiglottitis
    • Larynx → Croup

Common Cold

  • Is a self-limited viral process
  • Etiology: Rhinovirus (most common)
  • Clinical features:
    • Symptoms typically develop 1-3 days after viral infections
    • Presenting symptoms include low-grade fever, rhinorrhea, cough, and sore throat.
    • Symptoms resolve within 7–10 days.
    • Persistent symptoms (>10 days) or persistent fever: Should prompt the clinician to evaluate for bacterial superinfection (e.g., sinusitis, acute otitis media)
  • Diagnosis: Is based on clinical features, The viral agent is rarely identified.
  • Management: The most important step is to ensure adequate hydration, particularly in young children Antibiotics have no role in the management
  • Complications: Otitis media is the most common complication

Chronic Allergic Rhinitis

  • Chronic nasal inflammation lasts longer than 12 weeks
  • Indication of chronic allergic rhinitis:
    • Allergic shiners → black discoloration under the eye
    • Dennie line → fold below the eye
    • Prominent skin fold
    • Salute
    • Pale nasal mucosa
    • Post-nasal drip/polyps
    • Conjunctivitis
    • Otitis Media with effusion

Sinusitis

  • Is infection of the paranasal sinuses
  • Development of the sinuses:
    • Ethmoid & maxillary sinuses are present at birth.
    • The sphenoid sinuses develop between 3 and 5 years of age
    • The frontal sinuses between 7 and 10 years of age.
  • Etiology: Streptococcus pneumoniae is the most common cause
  • Clinical features:
    • Persistent rhinorrhea, nasal congestion, and cough, especially at night.
    • Symptoms should be persistent & not improving for more than 10 days → distinguish sinusitis from a URI
  • Chronic Sinusitis: Is defined by duration >12 weeks

Pharyngitis

  • Inflammation of the pharynx, resulting in a sore throat
  • Etiology: Adenovirus is the most common, Streptococcus pyogenes (Group A β-Hemolytic Streptococcus or strep throat)
  • GABHS pharyngitis (strep throat):
    • Is usually seen in school aged children (5–15 years of age), Most commonly in the winter and spring
    • GABHS infection has the following characteristics:
      • Lack of other URI symptoms (e.g., rhinorrhea, cough)
      • Exudates on the tonsils, petechiae on the soft palate, strawberry tongue
      • Enlarged tender anterior cervical lymph nodes
      • Fever
    • Diseases can caused:
      • Scarlet fever
      • Necrotizing fasciitis: results in the death of parts of the body's soft tissue
      • Impetigo
    • Diagnosis:
      • Culture (gold standard)
      • Antigen testing (“rapid strep test”)
      • Because 5% of the population carries GABHS in the pharynx (GABHS carriers), culture or rapid antigen testing should be limited to symptomatic patients who lack concomitant viral symptoms.
    • The drug of choice for treatment of bacterial pharyngitis:
      • Is oral penicillin for 10 days or IM benzathine penicillin
    • Complications:
      • Cervical lymphadenitis
      • Acute rheumatic fever (0.3-3%)
      • Acute glomerulonephritis
      • Sepsis
      • Retropharyngeal abscess:
        • Posterior wall thickness

Acute Diffuse Otitis Externa

  • Diffuse inflammation of external ear canal which may spread to involve the pinna & tympanic membrane.
  • Acute → less than 6 weeks
  • The most common pathogenic organisms responsible for external otitis are:
    • Pseudomonas aeruginosa (38%)
    • S. epidermidis (9%)
    • Staphylococcus aureus (8%)
  • The most common symptoms of external otitis are: Ear pain , Pruritus, discharge, Conductive hearing loss

Acute Otitis Media

  • Infection of the middle ear
  • Bacterial:
    • Streptococcus pneumonia (35%)
    • H.influenza (25%)
    • Moraxella catarrhalis (15%)
  • Symptoms:
    • Otalgia: may be slight in mild cases, but usually it’s throbbing and severe.
    • Difficulty hearing: always present in acute otitis media, conductive in nature and may be accompanied by tinnitus, Fussiness & Irritability ,Pulling or rubbing the ear
  • Signs:
    • Pyrexia (temperature may be as high as 40oC).
    • Tenderness to pressure on the mastoid process.
    • Tympanic membrane changes in appearance: Red, tense, bulging, Mucoid discharge from ear if TM perforates, Loss of light reflex
  • Treatment:
    • High dose Amoxicillin 80-90 mg/kg/day ; used in recurrent cases
    • In resistance (more than 3 days duration of treatment with Amoxicillin and still persistent) we use Amoxicillin + clavulanic acid
    • If amoxicillin failed → 3rd generation cephalosporins

Chronic Otitis Media

  • Painless, recurrent otorrhea for at least ≥ 2 weeks
  • Most common microorganisms:
    • Pseudomonas aeruginosa → greenish discharge
    • Staphylococcus aureus

Conjunctivitis – Otitis Syndrome

  • A condition characterized by concurrent purulent conjunctivitis and acute otitis media
  • Most common cause Non typable type H. influenza
  • Treatment: amoxicillin – clavulanic acid

Croup (Laryngotracheobronchitis)

  • Infection of the larynx and trachea in children and causing breathing difficulties
  • Etiology:
    • Parainfluenza viruses Type 1 → the most common
    • Respiratory Syncytial Virus (RSV)
    • Influenza
    • Adenovirus
  • Signs & symptoms:
    • Low-grade fever
    • Rhinorrhea
    • Inspiratory stridor (barking cough): Most common cause of stridor in 2 years old child and under
    • Hoarseness of Voice
  • X-ray finding: Steeple Sign
  • Management:
    • Oral or intramuscular dexamethasone → reduce croup severity and duration
    • Patients with moderate/severe croup: Add nebulized epinephrine
  • The most common complication of croup is viral pneumonia

Epiglottitis

  • Is a bacterial infection of the epiglottis & is consider as Medical emergency
  • Etiology: Haemophilus influenzae type b (HIB) → the most common cause
  • Clinical features:
    • Abrupt onset of rapidly progressive upper airway obstruction
    • High fever and toxic appearance
    • Dysphagia with drooling
    • Presented with sniffing or tripod position
    • Use Tongue depressor is contraindicated: Cause spasm & complete closure of airway & sudden respiratory arrest
  • X-ray finding: Thumbprint Sign
  • Management:
    • Admission
    • Secure airway (e.g. intubation): Most important step & is done by anesthesiologist
    • IV second- or third-generation intravenous cephalosporin to cover HIB and Streptococcus
    • Rifampin prophylaxis: Is indicated for unimmunized household contacts with epiglottitis secondary to HIB younger than 4 years of age

Cystic Fibrosis

  • An autosomal recessive disorder caused by mutation of the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) gene, which leads to defective chloride channels & hyperviscosity of exocrine gland secretions
  • Cystic Fibrosis Transmembrane conductance Regulator (CFTR) gene:
    • Found in chromosome 7
    • Code for Chloride channel
  • In sweat duct:
    • Chloride channel → reabsorb Cl- → no Cl- in sweats
    • No chloride channel → Cl- get out the sweat
  • In other parts of the body (e.g. airway , GI tract):
    • Chloride channel → Cl- go out to the lumen → water follow the Cl- → hydrate the mucus
    • No chloride channel → Cl- can not go out to the lumen → water can not go to the lumen → the mucus become very viscous
  • Clinical Presentation:
    • Clubbing
    • Respiratory system:
      • Majority of morbidity and mortality is related to lung diseases
      • Thick mucus obstruct the airway which lead to:
        • Cough
        • Tachypnea
        • Recurrent Infection (pneumonia) by pseudomonas aeruginosa:
          • Associated with poor pulmonary morbidity
          • Anti-Pseudomonal antobiotic:
            • A. Ureidopenicillins: Pipercillin, Carbenicillin, Ticarcillin.
            • B. One 3rd gen Cephalosporin: Ceftazidime.
            • C. One 4th gen Cephalosporin: Cefepime.
            • D. Carbapenems: Meropenem & her sisters. except: Ertapenem!
            • E. Aminogycosides
            • F. Fluoroquinolones: Ciprofloxacin
      • Bronchiectasis:
        • An irreversible and abnormal dilation of the bronchial tree caused by repeated and progressive airway destruction
        • This is the cause of respiratory failure in CF
      • Nasal polyps: When you find it, screen for CF
    • Gastrointestinal tract:
      • Meconium ileus:
        • Delay of the passage of meconium >48 hours after birth because of the thick intestinal secretions
        • 15% of CF newborns
      • Prolonged jaundice: The bile will be thick in the liver, so they develop obstructive Jaundice.
      • Pancreatic insufficiency:
        • In 85-90% of CF
        • Greasy stool (Steatorrhea)
        • Flatulence
        • Abdominal bloating
        • Poor weight gain
        • Fat-soluble-vitamin deficiency:
          • Vit A deficiency → leads to night blindness
          • Vit K deficiency → increase the bleeding tendency
          • Vit E deficiency → leads to hemolytic anemia & neuropathy
          • Vit D deficiency → leads to osteoporosis
        • May develop DM because the pancreas loss the ability to secrete insulin
    • In male:
      • Infertility Because of:
        • Obstructive azoospermia (98%)
        • Congenital Bilateral Absence of the Vas Deference (CBAVD)
  • Diagnosis:
    • Pilocarpine-induced sweat test:
      • Gold standard for testing for CF
      • Pilocarpine is muscarinic agonist → increase sweating
      • Sweat for chloride concentration:
        • Normal: < 40 mmol/L
        • Positive for CF: > 60mmol/L
        • Intermediate: 40-60 mmol/L (need further investigations)
      • We should repeat the test twice even it was +ve to diagnose CF
    • False Positive Sweat Test:
      • Adrenal insufficiency or stress
      • Anorexia nervosa
      • Ectodermal dysplasia
      • Eczema
      • Fucosidosis
      • G6PD deficiency
      • Glycogen storage disease type1
      • Hypoparathyroidism
      • Malnutrition
      • Nephrogenic diabetes insipidus
      • Psuedohypoaldosteronisim
    • False Negative Sweat Test:
      • Dilution of sample
      • Malnutrition
      • Peripheral edema due to hypoalbuminemia
      • Hypoproteinemia
      • Dehydration
      • Poor technique/inadequate sweat collection
      • HIV infection
      • Hypothyroidism
    • Assessment of Pancreatic Function:
      • Fecal elastase:
        • Is the gold standard
        • Sensitivity and specificity is 100% in CF
        • Isn’t affected by the pancreatic enzyme replacement.
        • It will be decreased in CF patients
    • Newborn screening:
      • Measure Immunoreactive trypsinogen level (one of the pancreatic enzymes ): Which will be elevated in CF because of the pancreatic injury
    • Management:
      • Airway clearance: Is done mainly by Chest Physiotherapy
      • Agents to promote airway secretion clearance: We put patients on nebulizers to liquefy the thick secretion in the airway.
      • Inhaled Mucolytics:
        • Inhaled recombinant DNAse (dornase alfa): It breaks the DNA of neutrophils, It’s expensive medication
        • N-acetyl-L-cysteine
        • Inhaled Hypertonic saline 7%
      • Antibiotic Therapy: To treat the infections, Given Nebulized or IV
      • Bronchodilator therapy: Beta 2 agonist Cystic fibrosis has higher incidence of asthma. Therefore, we have to give them bronchodilators and anti-inflammatory drugs
      • High energy and calorie diet: They need more than the regular amount of calories (100-120kcal/kg/day)
      • Fat-soluble vitamin supplementation and minerals
      • Pancreatic enzyme replacement
      • Preventive Care:
        • Annual influenza vaccine
        • Pneumococcal vaccine
        • Respiratory Syncytial Virus prophylaxis < 2 years
      • Trikafta medications: Made up of 3 substances: Elexacaftor, Tezacaftor, Ivacaftor, Work by increasing CFTR channel & improve its function, Reduce severe lung disease by 60%, Reduce the number of deaths by 15%, Increase life expectancy by several years

Asthma

  • A chronic disease in which the bronchial airways in the lungs become narrowed, making it difficult to breathe
  • Prevalence in Jordan is 10%
  • Pathophysiology of airway narrowing & obstruction:
    • Inflammation & Edema with Influx of inflammatory cells into the airway and Epithelial cell shedding
    • Bronchial smooth muscle spasm and hypertrophy
    • Mucus plugging
  • Predisposing to asthma
    • Frequent wheezing in the first year of life
    • Eczema
    • Maternal smoking
    • Maternal history of asthma
    • Positive family history
    • Elevated IgE levels
    • Male gender
  • Clinical manifestations:
    • Nocturnal symptoms are common
    • Cough, Wheeze & Shortness of breath
    • Tachypnea → wash out of CO2CO_2 → respiratory alkalosis
      • In acute asthma severe exacerbation → low PCO2PCO_2
      • In chronic asthma severe exacerbation → high PCO2PCO_2
    • Common exacerbating factors include:
      • Most common triggering factor in infant is Viral URTI
      • Most common triggering factor in older child is Exercise
    • Symptoms of Severe exacerbation:
      • Speaks in single words
      • Sits hunched forward, Agitated
      • Respiratory rate > 30 breaths per minute
      • Heart rate > 120 beats per minute
      • SpO2 (on air) <90%