TOPIC 14: Emesis (Infants) – Know the differential diagnosis and evaluation of emesis in an infant
OFFICIAL ABP TOPIC:
Emesis (Infants) – Know the differential diagnosis and evaluation of emesis in an infant
BACKGROUND
Vomiting is a common presenting symptom in infants that has a wide differential diagnosis spanning gastrointestinal, neurologic, metabolic, infectious, and other etiologies. While often benign and self-limited, emesis in infants can also be a sign of a serious underlying disorder.
DIFFERENTIAL DIAGNOSIS OF EMESIS IN INFANTS
TABLE 1
|
DISORDER |
TYPICAL CLINICAL FEATURES |
|
Gastrointestinal Obstruction |
|
|
Pyloric stenosis |
Forceful vomiting, typically nonbilious, beginning at 3-6 weeks of age, hypochloremic metabolic alkalosis, palpable “olive” |
|
Malrotation with volvulus |
Sudden onset of bilious vomiting and acute abdomen, starting at any age |
|
Intestinal atresia, stenosis, or duplication |
Bilious vomiting (if lesion distal to ampulla of Vater) and gastric or abdominal distension, usually presenting within hours or days of birth |
|
Intussusception |
Sudden-onset intermittent colicky pain, currant jelly stools |
|
Hirschsprung disease |
Abdominal distension, failure to pass meconium within 48 hours, sometimes with bilious emesis; can present with enterocolitis (fever, vomiting, diarrhea, septic shock) |
|
Other Gastrointestinal Causes |
|
|
Uncomplicated GER |
Infant with regurgitation but otherwise healthy (happy spitter) |
|
Overfeeding |
Frequent small-volume emesis, normal growth and development |
|
Infant rumination syndrome |
Re-swallowing of regurgitated food within minutes of eating; onset typically between 3-8 months old |
|
Viral gastroenteritis |
Sudden onset, usually with diarrhea and ill contacts |
|
Necrotizing enterocolitis (premature infants) |
Bilious emesis, bloody stools, abdominal distension, wall erythema/discoloration, acute decompensation |
|
GERD with esophagitis |
Frequent regurgitation with concerning symptoms (irritability, feeding refusal, poor weight gain) |
|
Food protein-induced enterocolitis syndrome (FPIES) |
Severe vomiting, diarrhea, lethargy in acute FPIES; chronic FPIES with intermittent vomiting, diarrhea, poor growth |
|
Eosinophilic esophagitis or gastroenteritis |
Feeding aversion, weight loss, hypoalbuminemia; can present with postprandial vomiting mimicking pyloric stenosis |
TABLE 1 CONTINUED…
|
DISORDER |
TYPICAL CLINICAL FEATURES |
|
Neurologic |
|
|
Hydrocephalus |
Persistent forceful emesis, bulging fontanelle, altered mental status, focal neurologic deficits, emesis with position changes |
|
Subdural hematoma |
Unexplained emesis, altered mental status, seizures in infant with history of possible trauma |
|
Metabolic/Endocrine |
|
|
Galactosemia |
Vomiting, jaundice, hepatomegaly, poor weight gain within days of starting breast milk or lactose-containing formula |
|
Hereditary fructose intolerance |
Vomiting, hypoglycemia after feeds with fructose/sucrose (fruits, juices, medications) |
|
Urea cycle defects, organic acidemias |
Recurrent vomiting, lethargy, poor feeding, ± hyperammonemia, metabolic acidosis |
|
Congenital adrenal hyperplasia |
Vomiting, dehydration, hypotension, hyponatremia, hyperkalemia; may have atypical genitalia (females) |
EVALUATION OF EMESIS IN INFANTS
HISTORY
- Emesis: Onset, frequency, amount, forcefulness, content (bilious, bloody, undigested food)
- Associated symptoms: Fever, diarrhea, bloody stools, abdominal pain/distension, lethargy
- Feeding: Formula or breast milk, volume, recent diet changes, timing of emesis relative to feeds
- Urine output and wet diapers
- Medications and recent immunizations
- Ill contacts: Gastroenteritis, HSV
- Growth and development
- Past medical history
- Family history: Gastrointestinal disorders, metabolic diseases, cystic fibrosis
PHYSICAL EXAM
- Vital signs
- Growth parameters (weight, length, head circumference): Rapid head growth may be a sign of hydrocephalus
- Hydration status: Tears, mucous membranes, skin turgor, sunken eyes/fontanelle
- General appearance: Lethargy, irritability, consolability
- Head: Fontanelle fullness, signs of trauma
- Abdomen: Distension, tenderness, visible peristalsis, palpable mass, bowel sounds
- Genitourinary: Atypical genitalia (congenital adrenal hyperplasia)
- Anus: Patency, explosive stools with rectal exam (blast sign suggestive of Hirschsprung’s disease)
- Neurologic: Mental status, tone, reflexes
- Skin: Jaundice, erythema/discoloration, petechiae/purpura
- Unusual odor may suggest a metabolic disorder (e.g., musty odor in phenylketonuria)
RED FLAGS FOR SERIOUS CAUSES OF EMESIS IN INFANTS
- Acute bilious emesis indicates a surgical emergency (e.g., malrotation with midgut volvulus, intestinal atresia or stenosis, necrotizing enterocolitis in premature infants, incarcerated hernia).
- Hematemesis: Differential includes swallowed maternal blood during birth (benign), esophagitis, Mallory-Weiss tear, coagulopathy (e.g., Vitamin K deficiency bleeding), gastritis/stress ulcers.
- Abdominal distension, tenderness, or mass.
- Altered mental status, irritability, lethargy.
- Jaundice in newborns >2 weeks old.
- Failure to thrive.
DIAGNOSTIC TESTING
- Lab tests: CBC, electrolytes, glucose, liver enzymes, urinalysis.
- Abdominal x-ray: If obstruction suspected, may show dilated loops of bowel, air-fluid levels.
- Abdominal ultrasound: Malrotation, hypertrophic pyloric stenosis, intussusception, masses.
- Upper GI contrast study: Malrotation, obstruction, pyloric stenosis.
- Metabolic screening: For persistent or unusual symptoms: ammonia, lactate, pyruvate, organic/amino acids, acylcarnitine.
- Brain MRI: For hydrocephalus.
- Endoscopy +/- biopsy: For suspected eosinophilic esophagitis or gastroenteritis.
- Specialized testing: Based on differential (e.g., sweat chloride for cystic fibrosis).
PHYSICAL EXAM FINDINGS AND DIAGNOSTIC CONSIDERATIONS
|
FINDING |
DIAGNOSTIC CONSIDERATIONS |
|
Nonspecific |
|
|
Tachycardia |
Dehydration, sepsis, metabolic acidosis, bowel ischemia |
|
Jaundice |
Conjugated – Biliary atresia, metabolic liver disease |
|
Unconjugated – Physiologic, breast milk, hemolysis, Gilbert syndrome |
|
|
Altered mental status |
Sepsis, meningitis, intracranial hemorrhage/mass, inborn error of metabolism, ingestion |
|
Poor growth/malnutrition |
Malabsorption, FPIES, eosinophilic disorders, metabolic disorders, pyloric stenosis |
|
Abdominal |
|
|
Distension |
Bowel obstruction, ileus, Hirschsprung disease, necrotizing enterocolitis |
|
Tenderness/peritoneal signs |
Intussusception, peritonitis, obstruction, volvulus |
|
Visible bowel loops |
Obstruction, Hirschsprung disease |
|
Abdominal mass |
Intussusception, tumor (neuroblastoma, Wilms), pyloric stenosis (“olive”) |
|
Jaundice + hepatomegaly |
Biliary atresia, idiopathic neonatal hepatitis, metabolic liver disease |
|
Other |
|
|
Bulging fontanelle |
Increased intracranial pressure, hydrocephalus, meningitis |
|
Inguinal mass/fullness |
Incarcerated inguinal hernia |
|
Rectal bleeding |
Milk protein allergy, FPIES, Meckel’s diverticulum, intussusception |
REFERENCES
https://www.uptodate.com/contents/approach-to-the-infant-or-child-with-nausea-and-vomiting
https://publications.aap.org/pediatricsinreview/article/39/7/342/35176/Vomiting-in-Children