[P1-166] A Case of Thrombotic Microangiopathy caused by Cobalamin C Defect with Favorable Neurological Outcomes
[Background] Cobalamin C (cblC) defect is the most frequent of congenital cobalamin disorders and a rare cause of thrombotic microangiopathy (TMA). Although untreated cblC defect leads to poor neurological outcomes, the recommended treatment with hydroxocobalamin, betaine and folic acid does not warrant normal development either. Furthermore, TMA is a life-threatening coagulopathy occasionally associated with poor neurological outcomes.
[Case report] A 62-day-old male infant had been previously diagnosed with and treated for methylmalonic acidemia based on the results of the newborn screening test. He was referred to our intensive care unit for the treatment of TMA presenting with intracranial and pulmonary hemorrhage, coagulopathy, and renal failure. The patient also had high plasma homocysteine and low methionine levels, which indicated cobalamin deficiency. A genetic analysis of the MMACHC gene confirmed the diagnosis of cblC defect. He was promptly treated with hydroxocobalamin and betaine, and his TMA symptoms improved rapidly. One year after treatment, he is alive and well with borderline development. His seizures are under control.
[Discussion] The present newborn screening program should be revised to detect cblC defect in order to avoid the development of TMA with poor neurological outcomes.
[Case report] A 62-day-old male infant had been previously diagnosed with and treated for methylmalonic acidemia based on the results of the newborn screening test. He was referred to our intensive care unit for the treatment of TMA presenting with intracranial and pulmonary hemorrhage, coagulopathy, and renal failure. The patient also had high plasma homocysteine and low methionine levels, which indicated cobalamin deficiency. A genetic analysis of the MMACHC gene confirmed the diagnosis of cblC defect. He was promptly treated with hydroxocobalamin and betaine, and his TMA symptoms improved rapidly. One year after treatment, he is alive and well with borderline development. His seizures are under control.
[Discussion] The present newborn screening program should be revised to detect cblC defect in order to avoid the development of TMA with poor neurological outcomes.