Differential Diagnosis for a 5-day-old Girl with Fussiness and Multiple Systemic Symptoms
- Single most likely diagnosis:
- D. Newborn inability to metabolize breast milk: The patient's symptoms, such as nonbloody, nonbilious vomiting after feeds, lethargy, poor tone, jaundice, and a sunken anterior fontanelle with overriding sutures, suggest a metabolic disorder. The most common condition that fits this presentation is galactosemia, a genetic disorder that affects the body's ability to metabolize galactose, a sugar found in breast milk. The presence of bilateral cataracts further supports this diagnosis, as galactosemia can cause cataract formation due to the accumulation of galactitol in the lens.
- Other Likely diagnoses:
- B. In utero fetal alcohol exposure: While the patient's symptoms do not directly point to fetal alcohol spectrum disorder (FASD), the mother's lack of prenatal care and potential for undisclosed substance use make this a consideration. However, FASD would not typically cause the acute metabolic symptoms seen in this patient.
- C. Maternal nonadherence to vaccination schedule: This option is less likely, as the patient's symptoms do not suggest an infectious etiology. However, it is essential to consider the risk of congenital infections, such as congenital rubella, which can cause cataracts and other systemic symptoms.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.):
- Infections (e.g., sepsis, meningitis): Although the patient's symptoms do not strongly suggest an infectious etiology, it is crucial to consider and rule out life-threatening infections, particularly in a newborn with a high pulse rate and lethargy.
- Congenital adrenal hyperplasia: This genetic disorder can cause adrenal insufficiency, leading to symptoms such as vomiting, lethargy, and dehydration. While less likely than galactosemia, it is essential to consider and rule out this condition.
- Rare diagnoses:
- E. Newborn inherited muscle dystrophy: This option is unlikely, as the patient's symptoms do not primarily suggest a muscular disorder. Muscle dystrophies typically present with progressive muscle weakness and wasting, rather than the acute metabolic symptoms seen in this patient.
- A. Advanced maternal age: While advanced maternal age can increase the risk of certain genetic disorders, it is not a direct cause of the patient's symptoms. The mother's age (36 years) is not considered advanced, and this option is not a relevant diagnosis in this case.