Chloe Ulett: Prevention of future deaths report

Hospital Death (Clinical Procedures and medical management) related deaths

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Date of report: 11/02/2026

Ref: 2026-0086

Deceased name: Chloe Ulett

Coroner name: Emma Brown

Coroner Area: Birmingham and Solihull

Category: Hospital Death (Clinical Procedures and medical management) related deaths

This report is being sent to: The Royal College of Emergency Medicine (‘RCEM’); 
The Royal College of Physicians |The Faculty of Intensive Care Medicine | The Royal College of Obstetricians and Gynaecologists |  The Royal College of Midwives.  

REGULATION 28 REPORT TO PREVENT FUTURE DEATHS
THIS REPORT IS BEING SENT TO:   
The Royal College of Emergency Medicine (‘RCEM’); 
The Royal College of Physicians; 
The Faculty of Intensive Care Medicine; 
The Royal College of Obstetricians and Gynaecologists; 
The Royal College of Midwives. 
1CORONER 
 I am Emma Brown, Area Coroner for the jurisdiction of Birmingham and Solihull
2CORONER’S LEGAL POWERS 
 I make this report under paragraph 7, Schedule 5, of the Coroners and Justice Act 2009 and regulations 28 and 29 of the Coroners (Investigations) Regulations 2013. 
3INVESTIGATION and INQUEST 
 On 4 August 2025 I commenced an investigation into the death of Chloe Angela ULETT. The investigation concluded at the end of the inquest hearing on the 11th February 2026.

The  conclusion of the inquest was; Natural causes.  
4CIRCUMSTANCES OF THE DEATH   
Miss Chloe Ulett died at Birmingham Heartlands Hospital on the 28th September 2024 from a  previously undiagnosed urea cycle disorder which had been unmasked by giving birth on the 10th September 2024.  

Miss Ulett had developed symptoms of excessive drowsiness and confusion by the early afternoon of the 13th September and attended for assessment at the maternity triage unit at Birmingham  Women’s Hospital that afternoon but she was diagnosed with iron deficiency and discharged. Her  altered mental state was not explained by anaemia, and she required admission for investigation. 

At home Miss Ulett’s symptoms increased and a call was made to the maternity unit triage who  wrongly advised to continue the treatment for iron deficiency and monitor Miss Ulett overnight  instead of advising that she should attend the emergency department. Due to further deterioration  an ambulance was called which transferred her to Birmingham Heartlands Hospital where she  arrived at 00:32 on the 14th September. By 3.18am she could not speak and had lost the ability to  use her arms or legs. Following medical assessment, her differential diagnosis was wide and  included suspected encephalitis, meningitis, cerebral venous sinus thrombosis, postpartum  infection and postpartum psychosis. The differential was gradually narrowed over the subsequent  days and by the evening of the 17th September a Urea Cycle Disorder was suspected based on  raised ammonia levels reported during the early hours of the 17th. Miss Ulett was started on  appropriate treatment initially with ammonia scavenging medications and then haemofiltration.  However, her prognosis at this point was very poor and she subsequently developed persistent  seizure activity and cerebral oedema. On the 23rd September it was concluded that there were no  further treatment options and her condition was terminal. 

Occurrence of undiagnosed urea cycle disorders in adults is rare. However, from the outset Miss  Ulett’s presentation warranted consideration of the Royal College of Emergency Medicine  guidance on acute behavioural disturbance which recommended testing of ammonia levels if  clinically indicated. Testing was clinically indicated by the 15th September. The decision to  discharge Miss Ulett on the 13th September and the delay in ammonia testing were missed  opportunities to improve Miss Ulett’s chance of survival but did not contribute to her death. 

Based on information from the Deceased’s treating clinicians the medical cause of death was determined to be: 
 1a   Hyperammonaemic encephalopathy 
 1b   N-acetylglutamate synthase deficiency 
5CORONER’S CONCERNS 
 During the course of the inquest the evidence revealed matters giving rise to concern. In my opinion there is a risk that future deaths will occur unless action is taken. In the circumstances it is my statutory duty to report to you. 

The MATTERS OF CONCERN are as follows.
1. 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.   

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

3. 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.   
4. 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. 

5. 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). 

6. The evidence was that this RCEM guidance is not yet embedded in adult medicine in the emergency department. 

7. 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. The RCEM guidance was updated in May  2025 but these matters have not changed from the 2023 version. 

8. 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.
  
9. It was further identified that 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. 

10. Following Miss Ulett’s 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.   

11. 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. 
6ACTION SHOULD BE TAKEN 
In my opinion action should be taken to prevent future deaths and I believe you have the power to take such action.   
7YOUR RESPONSE 
You are under a duty to respond to this report within 56 days of the date of this report, namely by 9 April 2026. I, the coroner, may extend the period. 

Given the cross-speciality relevance of the issues in this case it would be acceptable for the  response to be made jointly on behalf of some or all the respondents. If this approach is taken  please state clearly on the face of the response which organisations it is from.   

Your response must contain details of action taken or proposed to be taken, setting out the  timetable for action. Otherwise you must explain why no action is proposed.   
8COPIES and PUBLICATION 
 I have sent a copy of my report to the Chief Coroner and to the following Interested Persons:
[REDACTED] 
Birmingham Women’s and Children’s NHS Foundation Trust   
University Hospitals of Birmingham NHS Foundation Trust. 

I have also sent it to NICE and the BMJ who might find it useful or of interest. 

I am also under a duty to send the Chief Coroner a copy of your response. 

The Chief Coroner may publish either or both in a complete or redacted or summary form. She may send a copy of this report to any person who she believes may find it useful or of interest. 

You may make representations to me, the coroner, at the time of your response, about the release or the publication of your response by the Chief Coroner. 
911 February 2026