Differential Diagnosis for Poor Weight Gain in a 13-Day-Old Infant
Single Most Likely Diagnosis
- Inadequate Breast Milk Intake: This is often the most common reason for poor weight gain in newborns, especially if the mother is having difficulty with lactation or if the infant is not latching properly.
Other Likely Diagnoses
- Gastroesophageal Reflux Disease (GERD): Infants with GERD may have poor weight gain due to frequent spit-up and discomfort after feeding.
- Infection: Congenital or acquired infections can lead to poor feeding and weight gain.
- Hypothyroidism: Congenital hypothyroidism can cause poor weight gain, among other symptoms.
- Cystic Fibrosis: This genetic disorder can lead to malabsorption and poor weight gain.
Do Not Miss Diagnoses
- Congenital Heart Disease: Infants with significant congenital heart disease may have poor weight gain due to increased metabolic demand and decreased feeding ability.
- Inborn Errors of Metabolism: Certain metabolic disorders can present with poor weight gain and may be life-threatening if not identified early.
- Intestinal Obstruction: Conditions like pyloric stenosis or intestinal atresia can cause vomiting and poor weight gain.
Rare Diagnoses
- Chromosomal Abnormalities: Certain chromosomal abnormalities, such as Turner syndrome or Down syndrome, can be associated with growth failure.
- Endocrine Disorders (e.g., Congenital Adrenal Hyperplasia): These disorders can affect growth and weight gain.
- Gastrointestinal Disorders (e.g., Hirschsprung's Disease): Conditions affecting the gastrointestinal tract can lead to poor weight gain due to malabsorption or feeding difficulties.