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Differential Diagnosis for 5 Week Old Not Eating and Projectile 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 projectile vomiting after feeding, which is consistent with the symptoms described. The age of the infant (5 weeks) also aligns with the typical presentation age for pyloric stenosis.

Other Likely Diagnoses

  • Gastroesophageal Reflux Disease (GERD): While GERD can cause vomiting, it is less likely to cause projectile vomiting. However, it's a common condition in infants and can lead to feeding difficulties.
  • Infectious Gastroenteritis: Viral or bacterial infections can cause vomiting and refusal to feed in infants. The presence of fever, diarrhea, or other signs of infection would support this diagnosis.
  • Milk Protein Allergy or Intolerance: An adverse reaction to milk proteins can cause gastrointestinal symptoms, including vomiting and feeding difficulties.

Do Not Miss Diagnoses

  • Intussusception: Although less common in this age group, intussusception is a life-threatening condition that requires prompt diagnosis and treatment. It can cause vomiting, abdominal pain, and bloody stools.
  • Volvolus or Malrotation: These conditions involve twisting of the intestines and can cause severe vomiting, abdominal pain, and potentially lead to intestinal ischemia if not promptly treated.
  • Hirschsprung's Disease: A congenital condition characterized by the absence of ganglion cells in the colon, leading to intestinal obstruction. It can present with vomiting, constipation, and failure to thrive.

Rare Diagnoses

  • Congenital Anomalies (e.g., Duodenal Atresia, Esophageal Atresia): These conditions are present at birth and can cause feeding difficulties and vomiting due to obstruction of the gastrointestinal tract.
  • Metabolic Disorders: Certain metabolic disorders, such as congenital adrenal hyperplasia or disorders of amino acid metabolism, can present with vomiting and refusal to feed due to metabolic crises.
  • Neonatal Opioid Withdrawal Syndrome: If the mother used opioids during pregnancy, the infant could experience withdrawal symptoms, including vomiting and feeding difficulties, after birth.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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