Differential Diagnosis for a 3-week-old with Forceful Vomiting
Single Most Likely Diagnosis
- Pyloric Stenosis: This condition is characterized by the thickening of the pylorus muscle, leading to gastric outlet obstruction. It typically presents with forceful, projectile vomiting in infants around 3 weeks of age, making it the most likely diagnosis given the age and symptomatology.
Other Likely Diagnoses
- Gastroesophageal Reflux Disease (GERD): While GERD can cause vomiting, it's usually less forceful than in pyloric stenosis. However, it's a common condition in infants and can lead to significant discomfort and feeding difficulties.
- Infectious Gastroenteritis: Viral or bacterial infections can cause vomiting in infants. The presence of fever, diarrhea, or exposure to sick contacts might support this diagnosis.
- Overfeeding or Incorrect Feeding Technique: Overfeeding or using an inappropriate nipple size can lead to forceful vomiting in infants.
Do Not Miss Diagnoses
- Intussusception: Although less common in this age group, intussusception is a life-threatening condition where a part of the intestine telescopes into another, causing bowel obstruction. Vomiting can be a presenting symptom, along with abdominal pain and bloody stools.
- Volvolus or Other Surgical Emergencies: Conditions like midgut volvulus can cause vomiting due to intestinal obstruction and are surgical emergencies.
- Congenital Anomalies (e.g., Duodenal Atresia, Tracheoesophageal Fistula): These conditions can present with vomiting and are critical to diagnose early for appropriate management.
- Metabolic Disorders: Certain metabolic disorders can cause vomiting in infants due to the accumulation of toxic substances. Early diagnosis is crucial for treatment.
Rare Diagnoses
- Food Protein-Induced Allergic Proctocolitis (FPIAP): An allergic reaction to certain proteins in the diet, which can cause vomiting among other symptoms.
- Eosinophilic Gastroenteritis: A rare condition characterized by eosinophilic infiltration of the gastrointestinal tract, leading to various symptoms including vomiting.
- Congenital Hypertrophic Pyloric Stenosis in Premature Infants: Though pyloric stenosis is more common in term infants, it can also occur in premature babies, albeit less frequently.