Differential Diagnosis for Upset Infant

The following differential diagnosis is organized into categories to help guide the thought process:

• Single Most Likely Diagnosis
  • Gastroesophageal reflux disease (GERD): This is a common condition in infants, characterized by the backflow of stomach contents into the esophagus, leading to discomfort and fussiness.
• Other Likely Diagnoses
  • Overfeeding or underfeeding: Incorrect feeding amounts can lead to discomfort and irritability in infants.
  • Gas and bloating: Swallowing air during feeding or sensitivity to certain foods can cause gas and bloating, leading to an upset infant.
  • Allergies or intolerances: Allergic reactions to milk proteins or other components in formula can cause upset and discomfort.
  • Infection (e.g., urinary tract infection, otitis media): Infections can cause irritability and fussiness in infants, often accompanied by other symptoms like fever or changes in urine output.
• Do Not Miss Diagnoses
  • Intussusception: A condition where a part of the intestine slides into another, which can cause severe abdominal pain, vomiting, and bloody stools. It's a medical emergency.
  • Volvulus: A twisting of the intestine that can cut off blood flow, leading to severe pain, vomiting, and potentially life-threatening complications.
  • Sepsis: A systemic infection that can present with non-specific symptoms in infants, including irritability, lethargy, and feeding difficulties.
  • Congenital heart disease: Some heart defects can cause feeding difficulties, sweating, and irritability due to decreased cardiac output or increased energy expenditure.
• Rare Diagnoses
  • Food protein-induced enterocolitis syndrome (FPIES): A rare condition causing severe vomiting, diarrhea, and dehydration after ingestion of specific food proteins.
  • Eosinophilic esophagitis: An inflammatory condition of the esophagus that can cause feeding difficulties, vomiting, and irritability due to an allergic response.
  • Metabolic disorders: Certain genetic disorders affecting metabolism can cause a range of symptoms, including irritability, feeding difficulties, and developmental delays.

Each diagnosis is considered based on the potential for the condition to cause an upset infant, with an emphasis on those that are life-threatening or require prompt medical intervention.