Document Type : original article


1 M.D, Fellowship of Pediatric Endocrinology & Metabolism, Department of Pediatrics, School of Medicine, Akbar Hospital, Mashhad University of Medical Sciences, Mashhad, Iran.

2 Mashhad University of medical sciences

3 Clinical Research Development Center, Akbar Hospital, Faculty of Medicine, Mashhad University of medical sciences, Mashhad, Iran

4 nursing and midwifery school, Mashhad University of Medical Sciences, Mashhad, Iran

5 Clinical Research Development Unit of Akbar Hospital ,Faculty of Medicine , Mashhad University of Medical Sciences, Mashhad, Iran

6 mashhad university of medicine ,pediatric endocrinology department



Background: Methylmalonic acidemia is a rare autosomal recessive disease in which there is a deficiency of intracellular cobalamin. This study aimed to assess the effectiveness of parenteral hydroxylcobalamin in the treatment of children with methylmalonic acidemia.
Method: This is a quasi-experimental study without a control group. The participants included under-18-year-old children with confirmed methylmalonic acidemia. There were only 17 patients with the inclusion criteria, all of whom were included in the study. They received 1mg hydroxylcobalamin injection for 3 or 7 days based on their clinical status. Data was gathered by a demographic questionnaire, along with laboratory tests of urine-MMA, and plasma homocysteine, measured before and after the intervention. Data analyses were performed using SPSS v. 26.
Results: The samples included 17 patients, most of whom were males (52.9%). They had various clinical manifestations consisting of hypotonia, seizure, verbal disorders, movement disorders, organomegaly, hematologic disorders, and ophthalmic disorders. The parenteral hydroxylcobalamin had a borderline significant effect on urine-MMA (p=0.05); this seems to be due to the sample shortage and can become strongly significant with sample increase.
Conclusion: The results revealed the effectiveness of parenteral hydroxylcobalamin in MMA patients. However, there is no standard guideline to suggest the perfect dose of it to acquire the optimum result; so it is suggested to conduct more clinical trials or cohort studies to be done.