Category Archives: Pediatrics

vomiting in neonates

Vomiting in Neonates (NICU): Comprehensive Differential Diagnosis

In neonates, vomiting may range from benign physiological regurgitation to a surgical emergency. A systematic approach is essential.


1. Gastrointestinal Causes

A. Physiological / Functional

  • Physiological gastroesophageal reflux (GER)
  • Overfeeding
  • Improper feeding technique
  • Aerophagia (swallowed air)
  • Delayed gastric emptying in preterm infants

B. Gastrointestinal Obstruction

High Intestinal Obstruction

Bilious vomiting is a surgical emergency until proven otherwise.

Esophageal

  • Esophageal atresia ± tracheoesophageal fistula
  • Esophageal stricture
  • Congenital esophageal stenosis

Gastric

  • Pyloric stenosis (typically 2–8 weeks)
  • Gastric volvulus
  • Gastric outlet obstruction
  • Antral web

Duodenal

  • Duodenal atresia
  • Duodenal stenosis
  • Annular pancreas
  • Malrotation with midgut volvulus
  • Ladd bands

Jejunal/Ileal

  • Jejunal atresia
  • Ileal atresia
  • Meconium ileus
  • Meconium plug syndrome
  • Small left colon syndrome

Colonic

  • Hirschsprung disease
  • Colonic atresia
  • Anorectal malformations

C. Inflammatory/Infectious GI Disease

Necrotizing Enterocolitis (NEC)

Common NICU cause:

  • Vomiting
  • Feed intolerance
  • Abdominal distension
  • Bloody stools

Spontaneous Intestinal Perforation

Enterocolitis

  • Bacterial
  • Viral
  • Fungal

2. Infectious Causes

Any neonatal sepsis can present with vomiting.

Systemic Sepsis

  • Early-onset sepsis
  • Late-onset sepsis

Common organisms:

  • Group B Streptococcus
  • Escherichia coli
  • Listeria monocytogenes
  • Klebsiella
  • Enterobacter
  • Staphylococcus aureus
  • CoNS
  • Candida

CNS Infections

  • Meningitis
  • Encephalitis
  • Brain abscess (rare)

Urinary Tract Infection

A very important cause of unexplained vomiting.


3. Metabolic and Endocrine Causes

Inborn Errors of Metabolism (IEM)

Consider especially when vomiting is associated with:

  • Lethargy
  • Acidosis
  • Hyperammonemia
  • Hypoglycemia

Disorders

Amino Acid Disorders

  • Maple syrup urine disease
  • Phenylketonuria
  • Homocystinuria

Organic Acidemias

  • Propionic acidemia
  • Methylmalonic acidemia
  • Isovaleric acidemia

Urea Cycle Disorders

  • OTC deficiency
  • CPS deficiency

Fatty Acid Oxidation Disorders

  • MCAD deficiency
  • VLCAD deficiency

Carbohydrate Disorders

  • Galactosemia
  • Hereditary fructose intolerance

Electrolyte Disorders

  • Hyponatremia
  • Hypernatremia
  • Hypokalemia
  • Hyperkalemia
  • Hypocalcemia
  • Hypercalcemia
  • Hypomagnesemia

Glucose Disorders

  • Hypoglycemia
  • Hyperglycemia

Endocrine Disorders

Congenital Adrenal Hyperplasia (salt-wasting)

  • Vomiting
  • Dehydration
  • Shock

Adrenal insufficiency

Congenital hypothyroidism

Hyperthyroidism (rare)


4. Neurological Causes

Raised intracranial pressure can cause vomiting.

Intracranial Hemorrhage

  • Germinal matrix hemorrhage
  • Intraventricular hemorrhage
  • Subdural hemorrhage

Hydrocephalus

  • Congenital
  • Post-hemorrhagic

Hypoxic-Ischemic Encephalopathy


CNS Malformations

  • Dandy-Walker malformation
  • Arnold-Chiari malformation

Seizures

May manifest as feed intolerance and vomiting.


5. Respiratory Causes

Severe respiratory distress

  • Respiratory distress syndrome
  • Pneumonia
  • PPHN
  • Congenital heart disease with heart failure

Mechanism:

  • Increased swallowed air
  • Gut hypoperfusion

6. Cardiac Causes

Congenital Heart Disease

Particularly:

  • Duct-dependent lesions
  • Heart failure states

Examples:

  • Coarctation of aorta
  • Hypoplastic left heart syndrome
  • Interrupted aortic arch

Congestive Cardiac Failure

  • Large VSD
  • PDA
  • Cardiomyopathy

Maternal Drug Exposure

  • Opioid withdrawal
  • SSRI exposure

NICU Medications

  • Caffeine
  • Theophylline
  • Erythromycin
  • Opioids
  • Iron supplements
  • Vitamin preparations

Feeding Intolerance

Common in preterm infants

Features:

  • Vomiting
  • Increased gastric residuals
  • Abdominal distension

Human Milk Fortifier Intolerance


Formula Intolerance


Cow’s Milk Protein Allergy

Can present with:

  • Vomiting
  • Blood in stool
  • Poor weight gain

9. Hepatobiliary and Pancreatic Causes

  • Neonatal hepatitis
  • Cholestasis
  • Biliary atresia
  • Pancreatitis (rare)
  • Choledochal cyst

10. Toxic Causes

  • Medication overdose
  • Hypervitaminosis
  • Accidental toxin exposure

Important NICU “Cannot Miss” Diagnoses

Any neonate with vomiting should be assessed urgently for:

  1. Malrotation with midgut volvulus
  2. Necrotizing enterocolitis (NEC)
  3. Sepsis
  4. Meningitis
  5. Congenital adrenal hyperplasia
  6. Inborn errors of metabolism
  7. Intestinal atresia
  8. Hirschsprung disease
  9. Pyloric stenosis
  10. Intracranial hemorrhage

Practical NICU Approach

Bilious Vomiting

Think:

  • Malrotation with volvulus
  • Intestinal atresia
  • Hirschsprung disease
  • Meconium ileus
  • NEC

→ Surgical consultation immediately.

Non-bilious Projectile Vomiting

Think:

  • Pyloric stenosis
  • GER
  • Overfeeding

Vomiting + Abdominal Distension

Think:

  • NEC
  • Obstruction
  • Sepsis

Vomiting + Shock

Think:

  • Sepsis
  • CAH
  • Volvulus
  • Metabolic disease

Vomiting + Lethargy/Seizures

Think:

  • Meningitis
  • IVH
  • Hypoglycemia
  • IEM
  • Electrolyte disturbance

For NICU practice, the highest-yield etiologies are GER/overfeeding, feeding intolerance of prematurity, NEC, sepsis, malrotation-volvulus, intestinal obstruction, CAH, and inborn errors of metabolism. These account for most clinically significant neonatal vomiting presentations.

Epiglottitis – 5 clinical features, Short Notes

Definition

Epiglottitis is an acute inflammation and swelling of the epiglottis (a flap of cartilage at the base of the tongue that prevents food from entering the airway).
It is a medical emergency because swelling can rapidly block the airway. (Mayo Clinic)


Anatomy and Function of Epiglottis

  • Located above the larynx.
  • Acts like a “lid” over the trachea during swallowing.
  • Prevents aspiration of food and liquids into the lungs.

Causes

Infectious Causes

  • Haemophilus influenzae type b (Hib) – classic cause in children
  • Streptococcus pneumoniae
  • Streptococcal species
  • Staphylococcus aureus
  • Viral or fungal infections (less common)

Non-infectious Causes

  • Hot liquid burns
  • Trauma to throat
  • Chemical injury
  • Smoking/vaping or inhaling drugs (Mayo Clinic)

Risk Factors

  • Lack of Hib vaccination
  • Weak immune system
  • Diabetes
  • Smoking
  • Young children (historically), though now more common in adults

Clinical Features

Symptoms

  • Severe sore throat
  • Fever
  • Difficulty swallowing (dysphagia)
  • Painful swallowing (odynophagia)
  • Drooling
  • Muffled or “hot potato” voice
  • Difficulty breathing
  • Stridor (high-pitched breathing sound)

Signs

  • Patient sits leaning forward (tripod position)
  • Anxiety/restlessness
  • Cyanosis in severe cases

Classic Presentation

“3 D’s” of Epiglottitis

  1. Drooling
  2. Dysphagia
  3. Distress (respiratory)

Diagnosis

Clinical Diagnosis

  • Do not aggressively examine throat in severe cases because it may worsen airway obstruction.

Investigations

  • Laryngoscopy
  • Neck X-ray → Thumb sign
  • Blood culture/throat swab
  • Pulse oximetry (Mayo Clinic)

Management

Emergency Management

  1. Secure airway first
    • Oxygen
    • Endotracheal intubation if needed
    • Rarely tracheostomy
  2. Medications
    • IV antibiotics
    • Corticosteroids
    • IV fluids
  3. ICU monitoring

Complications

  • Sudden airway obstruction
  • Respiratory failure
  • Sepsis
  • Death if untreated (Mayo Clinic)

Prevention

  • Hib vaccination is the best preventive measure.
  • Good hygiene and infection control.

Difference Between Epiglottitis and Croup

FeatureEpiglottitisCroup
OnsetSuddenGradual
FeverHighMild
CoughUsually absentBarking cough
DroolingPresentRare
VoiceMuffledHoarse
AgeOlder children/adultsYoung children
EmergencySevere emergencyUsually mild

Key Points to Remember

  • Life-threatening airway emergency.
  • Drooling + stridor + muffled voice = suspect epiglottitis.
  • Do not force throat examination.
  • Airway management is priority.
  • Hib vaccine greatly reduced cases.

Epiglottitis

8 Clinical Features of Hypertrophic Pyloric Stenosis (HPS) — High-Yield Notes

Definition

  • Hypertrophy + hyperplasia of pyloric muscle → gastric outlet obstruction in infants.

Epidemiology

  • Age: 2–8 weeks (classically 3–6 weeks)
  • More common in:
    • First-born males
    • Formula-fed infants
    • Positive family history
  • Associated with macrolide exposure (e.g., erythromycin)

Pathology

  • Thickened pyloric muscle narrows pyloric canal.
  • Causes obstruction to gastric emptying.

Clinical Features

Classic Triad

  1. Projectile non-bilious vomiting
  2. Visible gastric peristalsis
  3. Olive-shaped mass in epigastrium/right upper abdomen

Other Findings

  • Hungry after vomiting (“hungry vomiter”)
  • Weight loss/dehydration
  • Constipation
  • Failure to thrive

Why Vomiting is Non-Bilious?

  • Obstruction is proximal to duodenum → bile cannot enter vomitus.

Electrolyte Abnormality (Very Important)

Due to repeated vomiting:

  • Hypochloremic
  • Hypokalemic
  • Metabolic alkalosis

Mnemonic:

“Vomiting loses HCl”


Diagnosis

Investigation of Choice

  • Ultrasound abdomen

USG Findings

  • Thickened pylorus
  • Elongated pyloric canal

X-ray/Barium

  • “String sign” (narrowed pyloric canal)

Management

Initial

  • Correct:
    • Dehydration
    • Electrolyte imbalance

Definitive Treatment

  • Ramstedt pyloromyotomy

Important Differentials

  • Gastroesophageal reflux
  • Duodenal atresia (bilious vomiting)
  • Intestinal obstruction
  • Sepsis/metabolic disorders

Super High-Yield One-Liners

  • Projectile non-bilious vomiting in a 3-week-old male = HPS until proven otherwise
  • Olive mass + visible peristalsis = classic clue
  • Best diagnostic test = Ultrasound
  • Treatment = Pyloromyotomy
  • Metabolic alkalosis is the classic acid-base disorder

Quick Revision Table

FeatureHPS
Age2–8 weeks
VomitingProjectile, non-bilious
AppetiteHungry after vomiting
MassOlive-shaped
DiagnosisUltrasound
ElectrolytesHypochloremic hypokalemic metabolic alkalosis
TreatmentRamstedt pyloromyotomy

6 Well Known Step Pathogenesis of Apnea of Prematurity Based on Nelson and Clohery to Clear Your Concept

Apnea of prematurity (AOP) is a common condition where infants born before 37 weeks gestation experience breathing pauses lasting 15-20 seconds or more, often accompanied by slow heart rates (bradycardia) or low oxygen levels. It stems from an immature central nervous system and usually resolves on its own by 37–40 weeks postmenstrual age. Based on Cloherty and Stark’s Manual of Neonatal Care (9th Edition) and relevant pediatric algorithms and Nelson’s, here is a comprehensive summary of Apnea of Prematurity (AOP).

1. Definition and Classification

  • Definition: Apnea is the cessation of airflow. It is considered pathologic (an apneic spell) when:
    • Absence of airflow lasts 20 seconds or longer.
    • It is shorter than 20 seconds but accompanied by bradycardia (heart rate < 100 bpm) or hypoxemia (cyanosis or $SpO_2$ < 85–80%).
  • Classification:
    • Central: Total absence of inspiratory efforts (no diaphragmatic activity).
    • Obstructive: Inspiratory efforts persist, but airflow is blocked, usually at the pharyngeal level.
    • Mixed: A combination where airway obstruction precedes or follows central apnea. Most spells in preterm infants are mixed.

2. Incidence, Onset, and Duration

  • Incidence: Inversely related to gestational age (GA). It occurs in essentially all infants < 28 weeks’ GA and about 25% of those < 34 weeks’ GA.
  • Onset: Typically begins 1 to 2 days after birth. If spells do not occur within the first 7 days, AOP is unlikely to develop later unless triggered by other factors.
  • Duration: Usually ceases by 36 to 37 weeks’ postmenstrual age (PMA) in infants born at $\ge 28$ weeks, but frequently persists beyond term for those born more prematurely.

3. Pathogenesis (Underlying Mechanisms)

  • Developmental Immaturity: The primary cause is an immature central respiratory drive in the brainstem.
  • Sleep State: Spells are more frequent during active (REM) sleep, which is the predominant sleep state in preterms and is characterized by irregular breathing.
  • Chemoreceptor Response: Preterm infants have a decreased ventilatory response to increased $CO_2$ and may respond to hypoxia with hypoventilation rather than sustained hyperventilation.
  • Reflexes: Apnea can be triggered by stimulation of the posterior pharynx (e.g., vigorous suctioning), lung inflation, or fluid in the larynx.
  • Airway Mechanics: Poor muscle tone can lead to airway obstruction, especially during neck flexion or if there is nasal obstruction.
  • Note on GER: While gastroesophageal reflux is common in preterms, studies have not demonstrated an association between GER and AOP frequency.

4. Differential Diagnosis (Evaluation)

Apnea in a term infant or a “sick” preterm infant is always abnormal and requires looking for secondary causes:

  • Infection: Sepsis, meningitis, or necrotizing enterocolitis.
  • Metabolic Disorders: Hypoglycemia, hypocalcemia, or electrolyte imbalances (hyponatremia).
  • Neurologic: Intracranial hemorrhage (IVH), seizures, or birth asphyxia.
  • Impaired Oxygenation: PDA (Patent Ductus Arteriosus), anemia, or pneumonia.
  • Drugs: Maternal medications (magnesium, narcotics) or drug toxicity (e.g., phenobarbitone).

5. Management and Treatment

  • Monitoring: All infants < 35 weeks’ GA should be monitored for at least the first week. Monitor heart rate and $SpO_2$ in addition to respiration.
  • Immediate Action: Respond to the infant, not the monitor alarm. Most spells respond to tactile stimulation. If the infant is unresponsive, use bag-and-mask ventilation.
  • Positioning: Avoid extreme neck flexion or extension. Prone positioning may reduce apnea by stabilizing the chest wall.
  • Pharmacotherapy (Methylxanthines):
    • Caffeine Citrate: The drug of choice due to its long half-life (once-daily dosing), high therapeutic index, and lack of need for routine level monitoring.
    • Dosing: Loading dose of 20 mg/kg (10 mg/kg caffeine base), followed by a maintenance dose of 5–10 mg/kg daily.
    • Benefits: Reduces spells, the need for mechanical ventilation, and the risk of Bronchopulmonary Dysplasia (BPD).
  • Respiratory Support:
    • nCPAP (4–6 $cm H_2O$): Reduces mixed and obstructive spells by maintaining end-expiratory lung volume.
    • NIPPV: May be attempted if CPAP fails.
  • Other Considerations:
    • Blood Transfusion: May be considered if the hematocrit is < 25–30% and spells are frequent despite caffeine.
    • GER Treatment: Pharmacologic treatment of reflux (e.g., H2 blockers) is not recommended to treat AOP and may be harmful.

6. Discharge and Follow-up

  • Discharge Criteria: Infants should be free of significant apnea for 5 to 7 days after stopping caffeine.
  • Caffeine Offset: Because caffeine effects remain for up to a week, the “countdown” to discharge typically starts several days after the last dose.
  • Recurrence: Recurrent apnea can be triggered by viral illness, anesthesia, eye examinations, or immunizations. These infants should be monitored closely until at least 44 weeks’ PMA.
  • SIDS: A history of AOP does not increase the risk of Sudden Infant Death Syndrome (SIDS).

Top 5 Facts about Gower’s Sign: How to easily demonstrate Gower’s sign?

Gowers’ sign is a medical sign that indicates weakness in the pelvic girdle and proximal lower limb muscles. It’s characterized by a patient using their hands to “walk” up their body to get to a standing position. 

10 red flags in a relationship that you should never ignore?

How is Gower’s Sign Performed?

  1. Start in a supine or sitting position
  2. Roll onto your stomach with your arms and legs extended
  3. Put your hands on the ground and shift your weight onto your extended arms
  4. Push your body backward to extend your legs
  5. Put your hands on your knees
  6. Walk your hands up your thighs until you’re standing

What it can indicate

  • Duchenne muscular dystrophy: A characteristic sign of this condition 
  • Guillain-Barré syndrome (GBS): Can be a sign of recovery from GBS 
  • Pelvic girdle weakness: A sign of weakness in the pelvic girdle and proximal lower extremity muscles 
  • Diskitis: Can be associated with diskitis at the L4-5 intervertebral space 

Who described it?

Gowers’ sign was described by neurologist Sir William Richard Gowers in 1879. 

Now lets dig into DMD.

Read now: Why is the MDF Stethoscope today’s No 1 Choice as Medical Professionals?

Duchenne Muscular Dystrophy (DMD)

Duchenne Muscular Dystrophy (DMD) is the most common and severe form of progressive muscular dystrophy in children. It belongs to a group of primary myopathies characterized by a progressive, genetic-based degeneration and death of muscle fibers.

1. Genetic Profile and Pathogenesis

  • Inheritance: DMD is an X-linked recessive disorder, almost exclusively affecting males and carried by females. Approximately one-third of cases result from de novo (new) mutations.
  • Molecular Defect: It is caused by a mutation (typically a deletion) in the gene for dystrophin located on chromosome Xp21.
  • Mechanism: Dystrophin is the longest known human gene and encodes a protein that connects the muscle fiber cytoskeleton to the surrounding extracellular matrix. Without functional dystrophin, muscle cells undergo chronic damage, necrosis, and replacement by fat and fibrous tissue.

2. Clinical Features

DMD typically presents between the ages of 2 and 5 years.

  • Early Signs: Delayed motor milestones (especially late walking) and mild speech or language delay are often the first indicators.
  • Muscle Weakness: Progressive, symmetric weakness begins in the pelvis and hip girdle, later involving the shoulder girdle.
  • Gait and Mobility: Affected children exhibit a waddling (Trendelenburg) gait, frequent falls, and difficulty climbing stairs (mounting them “one by one”).
  • Gower Sign: A classic clinical finding where the child, unable to stand up normally from the floor, must turn prone and “climb up his own thighs” with his hands to reach an upright position.
  • Pseudohypertrophy: Striking enlargement of the calf muscles occurs because muscle tissue is replaced by fat and connective tissue rather than true muscle growth.
  • Intellectual Function: Approximately 20% to 30% of boys have learning difficulties or non-progressive intellectual impairment.

3. Diagnostic Evaluation

Diagnosis should be initiated at the first clinical suspicion.

  • Serum Creatine Kinase (CK): Remarkably high levels (usually 10 to 40 times normal) are a hallmark of the disease.
  • Genetic Testing: Direct dystrophin gene testing is now the preferred definitive method and often avoids the need for a muscle biopsy.
  • Electromyography (EMG): Shows a “myopathic” pattern, including reduced amplitude and duration of motor unit potentials.
  • Muscle Biopsy: If performed, shows fiber necrosis, phagocytosis, and increased endomysial fat and connective tissue.

4. Progression and Complications

  • Loss of Ambulation: Most boys become wheelchair-bound by age 10 to 13.
  • Orthopedic: As weakness progresses, many develop scoliosis, particularly once they are no longer walking.
  • Cardiac: Progressive cardiomyopathy and persistent tachycardia develop in nearly all patients.
  • Respiratory: Weakness of the diaphragm and intercostal muscles leads to nocturnal hypoxia and eventual respiratory failure.
  • Prognosis: Death typically occurs in the late teens or 20s from cardiorespiratory complications.

5. Management

Management requires a specialist multidisciplinary team.

  • Corticosteroids: (e.g., Prednisone or Deflazacort) are the mainstay of treatment, as they preserve mobility, improve muscle strength, and prevent scoliosis.
  • Supportive Care: Physiotherapy and splinting are used to prevent contractures. Nocturnal hypoxia may be managed with overnight CPAP.
  • Novel Therapies: Research into exon-skipping drugs (e.g., Ataluren or Eteplirsen) allows for the production of small amounts of functional dystrophin in patients with specific mutations.
  • Genetic Counseling: Crucial for the family to detect female carriers and discuss antenatal diagnosis.

DMD vs. Becker Muscular Dystrophy (BMD): BMD is a milder allelic variant where some functional dystrophin is produced. BMD features a later onset (average 11 years), a slower course, and patients typically remain ambulatory into their late 20s or beyond, with many living into middle age.

Who described Gower’s sign?

Sir William Richard Gowers

What can Gower’s Sign indicate?

Duchenne muscular dystrophy, Guillain-Barré syndrome (GBS), pelvic girdle weakness, and diskitis.