Failure to Thrive, Metabolic Acidosis, and Diarrhea in a 7-Week-Old Infant

Area of Science:

• Pediatrics
• Neonatology
• Metabolic Disorders

Background:

• A 7-week-old infant presented with severe symptoms including metabolic acidosis, hypokalemia, elevated lactate, and hyperammonemia.
• The infant also exhibited failure to thrive, malnutrition, anemia, and vitamin D deficiency.

Purpose of the Study:

• To investigate the cause of severe metabolic derangements and failure to thrive in a neonate.
• To identify a diagnosis based on clinical presentation and response to therapeutic interventions.

Main Methods:

• Clinical assessment and resuscitation in the emergency department.
• Extensive laboratory workup for metabolic, nutritional, and electrolyte abnormalities.
• Intensive care unit (ICU) management including intravenous fluid and electrolyte replacement, bowel rest, and respiratory support.
• Trial of enteral feeding and observation of clinical response.

Main Results:

• Initial resuscitation and supportive care led to stabilization.
• Recurrence of severe symptoms, including loose stool and electrolyte abnormalities, upon reintroduction of enteral feeds.
• Refractory nature of symptoms to standard enteral supplementation.
• A diagnosis of exclusion was reached based on the patient's clinical course and response to therapy.

Conclusions:

• The infant's presentation mimicked severe metabolic and nutritional deficiencies.
• The clinical response to therapy, particularly the recurrence of symptoms upon enteral feeding, was crucial for diagnosis.
• Diagnosis of exclusion underscores the complexity of rare pediatric metabolic disorders and the importance of integrated clinical and laboratory findings.