| Autor: |
Tsykunova G; Department of Medicine Haukeland University Hospital, Bergen, Norway., Kristensen E; Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway., Stray-Pedersen A; The National Unit for Newborn Screening, Division of Paediatric and Adolescent Medicine, Oslo University Hospital, Oslo, Norway.; Faculty of Medicine, University of Oslo, Oslo, Norway., Bruserud Ø; Department of Anesthesiology and Intensive Care, Haukeland University Hospital, Bergen, Norway., Sørensen IW; Department of Medical Genetics, Haukeland University Hospital, Bergen, Norway., Bruserud Ø; Department of Medicine Haukeland University Hospital, Bergen, Norway.; Section for Hematology, Department of Clinical Science, University of Bergen, Bergen, Norway., Tvedt THA; Department of Medicine Haukeland University Hospital, Bergen, Norway.; Department of Haematology, Oslo University Hospital, Oslo, Norway. |
| Abstrakt: |
Hyperammonemia is a rare and often fatal complication following the conditioning therapy in autologous and allogeneic stem cell transplant recipients. It is characterized by anorexia, vomiting, lethargy and coma without any other apparent cause. The diagnosis is often delayed because symptoms can be subtle and ammonia is usually not included among the routine analyzes. Previous reports have not identified the molecular mechanisms behind hyperammonemia in stem cell transplant recipients. Urea cycle disorders (UCDs) are inborn errors of metabolism leading to hyperammonemia that usually presents in early childhood, whereas first presentation in adults is less common. Here we describe an adult woman with hyperammonemia following autologous stem cell transplantation for multiple myeloma. No apparent cause of hyperammonemia was identified, including portosystemic shunting, liver dysfunction or recent hyperammonemia-inducing chemotherapy. Hyperammonemia, normal blood glucose as well as anion gap and a previous history of two male newborns that died early after birth, prompted biochemical and genetic investigations for a UCD. A heterozygous variant in the X-linked gene encoding ornithine transcarbamylase (OTC) was identified and was regarded as a cause of UCD. The patient improved after treatment with nitrogen scavengers and high caloric intake according to a UCD protocol. This case report suggests that UCD should be considered as a possible cause of hyperammonemia following stem cell transplantation. |
