Chloe Ulett

“The window of opportunity to consider and make a diagnosis of a metabolic disorder and institute effective treatment is very short, 24 to 48 hours from the commencement of symptoms, and relies on early measurement of ammonia in an adult presenting with behavioural change and confusion”

“There are no identified NICE or BMJ best practice guidelines which currently recommend testing of ammonia levels for undifferentiated acutely presenting confused patients”

“Nationally, early measurement of ammonia levels in adults presenting to the emergency department and other units for investigation and management of behavioural change and confusion are not routine practice”

“The Royal College of Emergency Medicine (RCEM) guideline 'Acute Behavioural Disturbance in Emergency Departments' (Oct 2023) was the most appropriate guideline at the time, it advises doing tests as clinically indicated including appropriate metabolic screen to include blood tests to check ammonia levels”

“The RCEM guidance was not, however, considered by any of the practitioners in this case (the deceased was treated in the emergency department, by the acute medical team and then in intensive care with several other specialities consulting before ammonia testing was recommended by neurology”

“Further, evidence was given that the content and phrasing of the RCEM guidance was not helpful in the context of a case of acute behavioural disorder resulting from a urea cycle disorder because urea cycle disorders or metabolic disorders ('ABD') are not contained in the table of potential factors leading to ABD presentation in section 1, and in section 4 the recommended investigations do not assist in identifying when metabolic screens, and specifically ammonia levels, are clinically indicated. Nor is it clear why ammonia levels are placed in brackets. Additionally, there is no guidance as to the appropriate referral pathway to be followed when ammonia levels are raised”

“It was acknowledged that the presentation of adults with undiagnosed Urea Cycle Disorders is very rare and ammonia levels will not normally be clinically indicated for patients with ABD. However, it is the rarity of these presentations and the likely inexperience of those outside inherited metabolic diseases teams that gives rise to the need for clear guidance”

“inherited metabolic disease specialists are aware that a previously undiagnosed urea cycle disorders may be unmasked by giving birth and present for the first time in the post-partum period with symptoms of altered GCS including confusion, excessive drowsiness, seizures but this association is not known outside this speciality even in those caring for women in the post-partum period”

“Following Miss [name redacted] death the University Hospitals of Birmingham NHS Foundation Trust ('UHB') assessed the speciality teams who could encounter patients presenting with altered consciousness due to unmasked previously undiagnosed urea cycle disorder and identified the relevant specialities were emergency medicine, acute medical, intensive care medicine and maternity services”

“Whilst UHB has done a lot of work internally with the specialities identified to raise awareness of the potential presentation of an unmasked previously undiagnosed urea cycle disorder to an emergency department with acute behavioural disturbance and the need for consideration of ammonia testing at an early stage, there remains a national risk from delay in diagnosis because ammonia testing has not been considered”