A Case of Late-Presenting Methylmalonic Acidemia from a Country Without Extended Newborn Screening
Abstract
Methylmalonic acidemia (MMA) is an autosomal recessive disorder that may be caused by a complete (mut0) or partial (mut-) deficiency of the
methylmalonyl-CoA mutase, by defects in the synthesis or transport of the co-factor, or by a deficiency in methylmalonyl-CoA epimerase. Most
patients with MMA present with such signs and symptoms as lethargy, feeding problems, tachypnea and hypotonia after breastfeeding within the
first few days or weeks of life. In untreated cases, life-threatening acidosis, hyperammonemic encephalopathy, coma and death can occur. In the
present study we emphasize the importance of the early suspicion of inherited metabolic disorders in the differential diagnosis and treatment of an
MMA case who applied to the emergency department with atypical clinical findings after the age of 1, and who rapidly developed coma findings.
Although MMA frequently presents itself during the first days of life, it should be kept in mind in the differential diagnosis of metabolic acidosis,
especially in older patients with a high risk of inherited metabolic disorders and with atypical clinical and laboratory findings.
Keywords
Metyhlmalonic Acidemia, Organic Acidemia, Ketoacidosis
Ethical Statement
Written consent was obtained from the patient and family members for photos.
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