@article {Strausse226716, author = {Claire Emma Strauss and Gayle Hann}, title = {Unusual first presentation of a metabolic disorder}, volume = {12}, number = {3}, elocation-id = {e226716}, year = {2019}, doi = {10.1136/bcr-2018-226716}, publisher = {BMJ Specialist Journals}, abstract = {An 8-month-old boy presented to hospital with a fever, irritability and {\textquoteleft}back arching{\textquoteright}. On examination, he demonstrated profound opisthotonic posturing and had tonsillitis. He had a full septic screen and was treated with broad spectrum antibiotics. Blood tests showed a transaminitis, raised alpha fetoprotein and deranged clotting. The clotting abnormalities and raised alpha fetoprotein persisted post discharge and an abdominal ultrasound showed steatosis, splenomegaly and bilateral increased renal cortical reflectivity. A full metabolic screen revealed type 1 tyrosinaemia. The opisthotonic posturing, a major part of this child{\textquoteright}s presentation, has not been reported as a presenting feature of tyrosinaemia. It was part of a {\textquoteleft}neurological crisis{\textquoteright} caused by tyrosinaemia and exacerbated by the intercurrent infection. These are known to occur in tyrosinaemia but not commonly as the first presentation. This represents an unusual presentation of a metabolic condition which, without intervention, can lead to severe hepatic, renal and neurodevelopmental complications.}, URL = {https://casereports.bmj.com/content/12/3/e226716}, eprint = {https://casereports.bmj.com/content/12/3/e226716.full.pdf}, journal = {BMJ Case Reports CP} }