Atypical Adult-Onset Methylmalonic Acidemia and Homocystinuria Presenting as Hemolytic Uremic Syndrome

• Author(s): Navarro, D ; Azevedo, A ; Sequeira, S ; Ferreira, AC ; Carvalho, F ; Fidalgo, T ; Vilarinho, L ; Santos, MC ; Calado, J ; Nolasco, F
• Date: 2018
• Persistent ID: http://hdl.handle.net/10400.17/3044
• Origin: Repositório do Centro Hospitalar de Lisboa Central, EPE
• Subject(s): Methylmalonic aciduria and homocystinuria; Thrombotic microangiopathy; Vitamin B12 metabolism; Case Report; HDE MTB; HSJ PAT CLIN; HCC NEF
• Document Type: Journal article
• Language: English
• Contributor(s): Repositório da Unidade Local de Saúde São José

Description

Thrombotic microangiopathy (TMA) syndromes can be secondary to a multitude of different diseases. Most can be identified with a systematic approach and, when excluded, TMA is generally attributed to a dysregulation in the activity of the complement alternative pathways-atypical hemolytic uremic syndrome (aHUS). We present a challenging case of a 19-year-old woman who presented with thrombotic microangiopathy, which was found to be caused by methylmalonic acidemia and homocystinuria, a rare vitamin B12 metabolism deficiency. To our knowledge, this is the first time that an adult-onset methylmalonic acidemia and homocystinuria presents as TMA preceding CNS involvement.