Transcobalamin II deficiency

The main symptom is megaloblastic anemia. The patients may present vomiting, poor growth and infections due to an immune deficiency (hypogammaglobulinemia), failure to thrive, lymphopenia, neutropenia, and thrombocytopenia. Patients can have also neurological signs and abnormal neutrophil function.


Diagnostic recommendations

Additional Information

Diagnostic laboratories



Therapeutic options

  • Intake of vitamin B12 per os or parenteral. Symptoms disappear completely, except when the diagnosis is delayed and neurological signs have become permanent.
  • Transcobalamin II deficiency, ORPHANET