Paediatric Biochemistry and Inborn Errors of Metabolism —
Training activity: 10

Details

Write a plan of investigation for two of the following in the context of a suspected inborn error:

• Hypoglycaemia
• Hyperammonaemia
• SUDI (sudden unexpected death in infancy)
• HAGMA (high anion gap metabolic acidosis)

Type

Entrustable training activity (ETA)

Evidence requirements

Evidence the activity has been undertaken by the trainee repeatedly, consistently, and effectively over time, in a range of situations. This may include occasions where the trainee has not successfully achieved the outcome of the activity themselves. For example, because it was not appropriate to undertake the task in the circumstances or the trainees recognised their own limitations and sought help or advice to ensure the activity reached an appropriate conclusion. ​

Reflection at multiple timepoints on the trainee learning journey for this activity.

Considerations

• Investigation of developmental delay and dysmorphism
• Test prioritisation
• Timelines and clinical urgency
• Non-specific tests to support diagnosis
• Clinical presentation, mechanism of disease, typical symptoms, and variant forms
• Local and national guidelines

Reflective practice guidance

The guidance below is provided to support reflection at different time points, providing you with questions to aid you to reflect for this training activity. They are provided for guidance and should not be considered as a mandatory checklist. Trainees should not be expected to provide answers to each of the guidance questions listed.

Before action

What does success look like?

• Identify what is expected of you in relation to writing a structured and logical plan of investigation for two acute metabolic presentations (Hypoglycaemia, Hyperammonaemia, SUDI, or HAGMA).
• Consider how the learning outcomes apply, specifically in relation to applying the appropriate testing strategy and selecting and performing the appropriate investigative strategy for common, acute presenting paediatric disorders.
• Discuss with your training officer to gain clarity of what is expected of you in relation to identifying critical initial biochemical work-up, correct sample types and handling requirements (e.g., ammonia on ice), and guiding further investigations (e.g., specialist referral tests).

What is your prior experience of this activity?

• Think about what you already know about the biochemical and clinical differences between adults and children and the major categories of inborn errors of metabolism (IEMs).
• Consider possible challenges you might face during the activity, such as identifying the key differential diagnoses for these acute conditions (e.g., IEMs) or designing a plan when initial biochemical findings are ambiguous.
• Recognise the scope of your own practice for this activity i.e. know when you will need to seek advice or help, and from whom. You will need to seek advice from your Training Officer when required, for example when you are uncertain about the specific collection or handling requirements (e.g., for amino acids or organic acids) or if required initial results are conflicting.
• Acknowledge how you feel about designing investigative pathways for potentially life-threatening acute presentations.

What do you anticipate you will learn from the experience?

• Consider the specific skills you want to develop, such as developing a structured and logical approach to investigating acute metabolic presentations and selecting the critical initial biochemical tests required urgently.
• Identify the specific insights you hope to gain into how to use initial biochemical findings (e.g., presence or absence of ketones) to guide subsequent testing and narrow down the potential IEM diagnosis, and the importance of correct sample collection and handling.

What additional considerations do you need to make?

• Consult actions identified following previous experiences of investigating complex or acute patient cases.
• Identify important information you need to consider before embarking on the activity, such as reviewing the diagnostic pathways for paediatric hypoglycaemia, hyperammonaemia, SUDI, and HAGMA, familiarising yourself with your laboratory’s protocols for investigating acute presentations, and understanding the specific sample requirements and turnaround times for key in-house and referral metabolic investigations.

In action

Is anything unexpected occurring?

• Are you noticing anything surprising or different from what you anticipate whilst developing the investigation plan for a suspected inborn error?
• Are you encountering situations such as:
  • Difficulties identifying the appropriate tests for the specific suspected inborn error or clinical presentation?
  • Challenges in considering the clinical context alongside potential inborn errors?
  • Issues with structuring the plan effectively?
  • Difficulties designing a plan when initial biochemical findings are ambiguous?
• Consider how this experience compared with previous experiences of similar activities, such as planning investigations for adult patients or different types of disorders.

How are you reacting to the unexpected development?

• How is this impacting your actions? For example, are you responding to the situation appropriately? Did you adapt or change your approach to developing the plan?
• Consider the steps you are taking in the moment, such as:
  • Consulting relevant guidelines or resources
  • Discussing with a supervisor
  • Rethinking the testing strategy
• How are you feeling in that moment? For instance, are you finding it difficult to adapt? Is it affecting your confidence? Did you feel positive you could reach a suitable conclusion?

What is the conclusion or outcome?

• Identify how you are working within your scope of practice while writing the investigation plan. For example, are you applying the appropriate testing strategy for paediatric clinical scenarios? Or are you needing support because the selection of appropriate specialist testing for categories of inborn errors requires senior confirmation?
• What are you learning as a result of the unexpected development? For example, are you gaining insight into applying appropriate testing strategies for paediatric clinical scenarios? Or selecting appropriate specialist testing for categories of inborn errors of metabolism relevant to hypoglycaemia, hyperammonaemia, SUDI, or HAGMA?

 

On action

What happened?

• Begin by summarising the key steps you took when writing the plan of investigation for the two selected scenarios.
• Consider specific events, actions, or interactions which felt important, such as the rationale used for selecting specific tests or investigations or how you consulted guidelines or resources while developing the plan.
• Include any ‘reflect-in-action’ moments where you had to adapt to the situation as it unfolded, for instance, immediately revising the order of investigations when realising the sample collection requirements for a critical test (e.g., ammonia handling) were highly specific.
• How did you feel during this experience, e.g., did you feel focused on developing a logical and structured approach or stressed by the potentially life-threatening nature of the suspected inborn errors?

How has this experience contributed to your developing practice?

• Identify what learning you can take from this experience regarding the appropriate testing strategy for these specific paediatric clinical scenarios when an inborn error of metabolism (IEM) is suspected. What strengths did you demonstrate, e.g., enhanced ability to select and perform (by planning) the appropriate investigative strategy for common, acute presenting disorders?
• What skills and/or knowledge gaps were evident, e.g., unfamiliarity with specific alternative investigative pathways for these conditions?
• Compare this experience against previous engagement with similar activities – were any previously identified actions for development achieved? Has your practice improved in applying the investigation of inborn errors to relevant scenarios?
• Identify any challenges you experienced, such as needing to seek advice or clarification on scope of practice regarding the specific collection requirements for highly specialised referral tests (e.g., organic acids), and how you reacted to this.

What will you take from the experience moving forward?

• Identify the actions or ‘next steps’ you will now take to support the assimilation of what you have learnt, including from any feedback you have received, with regards to key steps or considerations to always include when planning investigations for suspected IEMs.
• What will you do differently next time you approach writing a plan of investigation for suspected IEMs, for instance, by proactively reviewing the diagnostic pathways for hypoglycaemia, hyperammonaemia, and HAGMA to ensure a comprehensive differential diagnosis?
• Do you need to practise any aspect of the activity further, such as researching specific categories of inborn errors of metabolism or key learning outcomes related to selecting and performing the appropriate investigative strategy for acute presenting disorders.

Beyond action

Have you revisited the experiences?

• How have your subsequent experiences of investigating acute paediatric cases or studying the presentation of specific inborn errors of metabolism (IEMs) since completing this specific training activity led you to revisit your initial approach or decisions during that activity? For example, how subsequently encountering an actual Hyperammonaemia patient case forced you to re-evaluate the speed and precision of initial sample collection requirements (e.g., ammonia on ice) outlined during your first attempt at writing the investigation plan.
• Considering what you understand about IEM diagnostic pathways, the urgency of investigation, and the specific requirements for referral tests (e.g., organic acids, amino acids) now, were the actions or considerations you identified after your initial reflection on this training activity sufficient? How have you since implemented or adapted improvements in your systematic differential diagnosis and test selection methodology based on further learning and experiences? For example, how you proactively reviewed and integrated guidelines for using initial biochemical markers (e.g., ketones) to guide subsequent specialist testing for suspected IEMs.
• Has discussing acute metabolic crises or the specific handling requirements for IEM diagnostic samples with colleagues, peers, or supervisors changed how you now view your initial experience in this training activity? For example, how professional storytelling with a senior colleague about a SUDI case where critical samples were lost due to improper storage refined your understanding of the critical nature of meticulous pre-analytical planning for IEMs.

How have these experiences impacted upon current practice?

• How has the learning from this initial training activity, in combination with subsequent metabolic interpretation and clinical case experiences, contributed to your overall confidence and ability in systematically investigating acute metabolic crises, particularly in preparing for assessments like CBDs? For example, how your accumulated ability in systematically designing investigative pathways for acute metabolic crises now enables you to confidently discuss initial biochemical work-up for a suspected Hyperammonaemia case during a CBD assessment.
• How has reflecting back on this specific training activity, combined with everything you’ve learned since, shaped your current approach to investigating acute paediatric metabolic issues? How does this evolved understanding help you identify when something is beyond your scope of practice or requires escalation? For example, how your evolved approach means you now routinely verifies specific collection and transport requirements (e.g., ammonia handling) and immediately seeks advice if the initial results suggest a rare IEM requiring specialised, complex referral testing.
• Looking holistically at your training journey, how has this initial IEM investigation planning experience, revisited with your current perspective, contributed to your development in meeting the learning outcomes related to applying the appropriate testing strategy and selecting and performing the appropriate investigative strategy for common, acute presenting paediatric disorders? For example, how this foundational experience has supported your development in contributing to clinical guidelines for suspected IEMs and thinking systematically about differential diagnoses.

Relevant learning outcomes

#	Outcome
# 1	Outcome Explain the biochemical and clinical differences between adults and children.
# 2	Outcome Employ knowledge of the technical issues associated with paediatric samples.
# 4	Outcome Apply the appropriate testing strategy for paediatric clinical scenarios.
# 6	Outcome Select and perform the appropriate investigative strategy for the common, acute presenting paediatric disorders.