Differential Diagnosis for the Newborn's Condition
- Single most likely diagnosis
- D. Anti-D antibodies: This is the most likely cause of the newborn's jaundice, given the presence of anti-Rh antibody titers in the mother's serum and her Rh-negative blood group. The mother's immune system has been sensitized to Rh-positive blood, likely from a previous pregnancy or blood transfusion, and has produced antibodies against the Rh factor. These antibodies can cross the placenta and cause hemolysis of the newborn's red blood cells, leading to jaundice.
- Other Likely diagnoses
- B. RBC enzyme deficiency: Although less likely, a red blood cell enzyme deficiency, such as glucose-6-phosphate dehydrogenase (G6PD) deficiency, could also cause jaundice in the newborn. This condition can lead to hemolysis and jaundice, especially in response to certain medications or infections.
- F. Anti-B antibodies: If the mother has a different blood type, such as type A, she may have developed anti-B antibodies, which could also cause hemolysis and jaundice in the newborn.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- A. Viral infection: Although less likely, a viral infection, such as herpes simplex or cytomegalovirus, can cause severe jaundice and other systemic symptoms in the newborn. It is essential to consider this possibility, as it requires prompt and specific treatment.
- E. Biliary duct malformation: A biliary duct malformation, such as biliary atresia, can cause obstructive jaundice and requires prompt surgical intervention to prevent long-term liver damage.
- Rare diagnoses
- C. RBC sickling: Although the newborn's brother has sickle cell disease, it is unlikely that the newborn has sickle cell disease, as it would require both parents to be carriers of the sickle cell trait. However, it is still possible, and further testing would be necessary to confirm or rule out this diagnosis.
- Other rare causes of jaundice, such as congenital infections (e.g., toxoplasmosis, rubella) or metabolic disorders (e.g., tyrosinemia), should also be considered, although they are less likely given the information provided.