It’s the beginning of your night shift when….
The emergency buzzer sounds from the waiting room. You rush over and find a 15-year-old girl on the floor, surrounded by staff. The triage nurse tells you she’s concerned the patient is having a seizure.
Her eyes are tightly closed, her head shaking from side to side, and her body jerking in irregular, non-rhythmic movements. The episode waxes and wanes before gradually coming to an end. She opens her eyes and starts speaking to you.
Her mother is distraught, she tells you this isn’t the first time – her daughter was seen in the department just last week and was sent home. She feels no one is taking her daughter’s seizures seriously.
How would you manage her?
Functional Neurological Disorder (FND) is one of the most challenging and often misunderstood conditions in paediatric emergency. As clinicians, it forces us to leave our comfort zone of structural diseases and diagnostic tests.
How FND presents doesn’t always fit the typical patterns of acute neurological conditions, yet the symptoms experienced by the patient are no less real. It can lead to poor quality of life, with high levels of mental and physical co-morbidities, so it’s important we get our management right.
So, how can we do this?
Let’s explore practical and effective ways to approach and manage FND in the emergency setting…
What is Functional Neurological Disorder (FND)?
Functional Neurological Disorder (FND) is a condition where patients experience dysfunction of their nervous system, without any underlying structural issue. Patients present with symptoms caused by altered brain networking and difficulty processing information that leads to real and involuntary symptoms.
Think of the brain like a city’s road network. In FND, the roads are all intact, the traffic lights are on, but something’s gone awry with the signals. The lights are changing out of sync and sending drivers into a spin. Chaos ensues, not because the lights are broken, but because the messages controlling the flow aren’t getting through.
This is the essence of FND; everything appears normal, yet the brain’s pathways are out of sync, leading to distressing and sometimes disabling symptoms.
How common is Functional Neurological Disorder?
FND is more common in children than many of us realise. While the exact figures in research vary, studies suggest that up to 15% of children referred to paediatric neurology clinics present with functional symptoms. Girls are more affected than boys, with onset in the early to mid-teen years.
Why do Functional Neurological Disorders occur?
We don’t fully understand the “why” of FND occurring, but current research is helping us to gain a clearer picture of “how”.
FND arises from a complex interaction of biological, psychological, and social factors. It’s often associated with stress, anxiety, trauma and adverse childhood experiences (ACEs), though not always. Neurologically, symptoms are caused by issues in the brain’s normal systems of attention and sensory processing. Research has noted that areas of the brain, such as the amygdala and prefrontal cortex (areas associated with emotion and executive functioning), can have a key role.
Several studies have reported that since the COVID-19 pandemic, presentations of FND have increased, possibly due to higher stress levels, disrupted routines, and greater exposure to functional symptoms on social media. Despite this, FND often remains under-recognised and poorly managed in acute care settings.
What might FND look like in ED?
Functional seizures (previously known as psychogenic nonepileptic seizures or PNES). These are paroxysmal episodes that can resemble seizures, but without EEG changes. They appear different from epileptic seizures and may be more prolonged, vary in intensity, lack a post-ictal phase, have asynchronous movements or occur with retained awareness or closed eyes.
Functional weakness or paralysis. Sudden onset of leg or arm weakness with normal reflexes and inconsistencies on examination.
Movement disorders. Abnormal gait patterns, tics or tremors that improve with distraction.
Visual or sensory changes. Loss of vision or sensation in patterns inconsistent with neuroanatomy.
Red flags
In the chaos of ED, our priority is to rule out acute structural or life-threatening conditions.
It’s important to say here that FND is not a diagnosis of exclusion. Historically, FND was diagnosed after ruling out all other causes, but this practice has led to over-investigation and delays in treatment, and ignores the positive signs of FND. With that said, as ED clinicians, we must ensure that our patients are not presenting with a life-threatening condition.
Here are some red flags for acute structural or life-threatening conditions that require prompt investigation:
- New-onset neurological symptoms with no previous episodes
- Progressive symptoms
- Symptoms in children younger than 6 years
- Headaches with focal neurology or vomiting
- Fever or altered mental state
- Consistently localised signs on examination
Once you’ve ruled out the critical conditions, you can then look for the positive signs of FND to make your diagnosis.
If you’re unsure, it’s okay to investigate, but try to avoid over-investigation once red flags are ruled out.
Diagnosing FND
The key to diagnosing FND is by recognising symptoms that are inconsistent, reversible, or don’t match patterns of other neurological presentations.
There are several positive signs that you can look for in the history and examination to help you with your diagnosis of FND:
- Distractibility: symptoms that improve when attention is diverted.
- Inconsistency: for example, a child who can’t move their arm but later is seen picking up their phone.
- Hoover’s sign: This can be used to test for functional weakness of the lower limbs. Place your hands under the patient’s heels whilst lying down and ask them to lift the affected leg. If the opposite heel presses down whilst trying to lift the affected leg, this indicates weakness resulting from acute structural or neurological damage, rather than a functional weakness.
- Midline splitting of sensory loss: neurological deficits rarely follow anatomical midlines. A child who reports weakness on the right but not the left, with numbness that stops exactly in the midline, is likely to be experiencing functional sensory loss.
Managing FND in the emergency setting
The first step is providing a clear explanation of the diagnosis. This can be difficult at times; the child is distressed, the family are scared, and they’ve been waiting in the department for hours, expecting answers and a solution.
It can be nerve-wracking, but one of the most powerful things you can do for this patient is to recognise and address the condition early. Explain that the symptoms are real, common and treatable, and reassure the patient that you don’t think they’re “faking it”. The key is to approach it with the same urgency and care as you would any other acute diagnosis.
From my assessment, I’m reassured that there are no signs of a life-threatening condition that needs emergency treatment.
That said, I want to be clear that what you’re experiencing is very real, and I don’t think these symptoms are something you’re imagining.
What you’re describing sounds like a condition called Functional Neurological Disorder, or FND.
It happens when the brain has difficulty sending and receiving information from the body, and it can cause a wide range of symptoms like the ones you’re having today.
It can sometimes be brought on by stress, and from what you’re telling me about the difficult time you’ve been going through recently,
I think these things could be related.
FND is actually quite common, and with the proper support, most people improve significantly over time.
I want to start that process by giving you some information and arranging the right referrals so we can begin helping you move forward.
The referrals required will vary based on the child’s presentation and psychosocial factors, but it’s essential to ensure ongoing paediatric follow-up to monitor progress and adapt management. It’s also important to maintain a low threshold for involving neurology if there is any uncertainty regarding the diagnosis or if symptoms persist.
Referrals may include:
- Child and Adolescent Mental Health Services (CAMHS): CBT, family therapy and trauma-focused interventions have all been shown to be effective in managing FND (6).
- Physiotherapy: If motor symptoms or loss of function are present.
- GP: GPs can provide continuity of care, as well as monitoring progress and allowing access to local services (physiotherapy, psychology, social care).
- School or educational support services: Though not a direct ED referral, it’s important to encourage the family to liaise with the school to arrange any necessary support and avoid time off, as this can reinforce symptoms.
Make sure to encourage the child and family to continue with a normal routine as much as possible, as limiting or avoiding activities can further perpetuate symptoms.
Information for families
This can all be a lot of information to take in at once, so resources to take away can be helpful. Here are some good websites to direct families to:
- https://www.gosh.nhs.uk/conditions-and-treatments/conditions-we-treat/functional-symptoms/
- https://neurosymptoms.org/en/
- https://www.nhsinform.scot/illnesses-and-conditions/brain-nerves-and-spinal-cord/functional-neurological-disorder/
A final thought
Children with FND are not trying to trick us. They’re often scared, confused, and desperate for answers. What they need is a calm, compassionate response that acknowledges their distress, validates their experience and offers hope for the future. It’s crucial to remember that FND is just another presentation of illness, and the way we approach and interact with these children can significantly influence their recovery journey.
Take-home messages:
FND is common, especially in children and teens living in stressful or difficult circumstances
It is not faking, it is not malingering, and it is not “just anxiety”
Early recognition and a clear explanation can make a huge difference.
Encourage normal routines and arrange appropriate referrals for long-term support.
References
Raper J, Currigan V, Fothergill S, et al. Long-term outcomes of functional neurological disorder in children. Arch Dis Child. 2019;104(12):1155-1160.
McFarlane F, et al. Cognitive-behavioural treatment of functional neurological symptoms (conversion disorder) in children and adolescents: A case series. European Journal Paediatric Neurology. 2019;23(2):159-164. doi:10.1016/j.ejpn.2018.12.002.
Stone J, Carson A, Duncan R, et al. Who is referred to neurology clinics? The diagnoses made in 3781 new patients. Clinical Neurosurgery. 2010;112(9):747-751. doi:10.1016/j.clineuro.2010.05.011.
Yong K, Chin RFM, Shetty J, Hogg K, Burgess K, Lindsay M, et al. Functional neurological disorder in children and young people: Incidence, clinical features, and prognosis. Dev Med Child Neurology. 2023;65(11):1238-1246. doi:10.1111/dmcn.15538.
Perjoc RS, Roza E, Vladacenco OA, Teleanu DM, Neacsu R, Teleanu RI. Functional neurological disorder–old problem, new perspective. International Journal Environmental Public Health. 2023;20(2):1099. doi:10.3390/ijerph20021099.
Aybek S, Perez DL. Diagnosis and management of functional neurological disorder. BMJ. 2022;376:o64. doi:10.1136/bmj.o64.
Hull M, Parnes M. Tics and TikTok: Functional tics spread through social media. Movement Disorders in Clinical Practice. 2021;8(10):1248-1252. doi:10.1002/mdc3.13267.
Pringsheim T, Ganos C, McGuire JF, Hedderly T, Woods D, Gilbert DL, et al. Rapid onset functional tic-like behaviors in young females during the COVID-19 pandemic. Movment Disorders. 2021;36(12):2707-2713. doi:10.1002/mds.28778.
Cock HR, Edwards MJ. Functional neurological disorders: acute presentations and management. Clinical Medicine (Lond). 2018;18(5):414-418. doi:10.7861/clinmedicine.18-5-414.
Bennett K, et al. A practical review of functional neurological disorder (FND) for the general physician. Clinical Medicine (Lond). 2021;21(1):56-61. doi:10.7861/clinmed.2020-0987.
Stone J, Carson A, Duncan R, Roberts R, Warlow C, Hibberd C, et al. Symptoms ‘unexplained by organic disease’ in 1144 new neurology out-patients: how often does the diagnosis change at follow-up? Brain. 2009;132(10):2878-2888. doi:10.1093/brain/awp220.
Finkelstein SA, Cortel-LeBlanc MA, Cortel-LeBlanc A, Stone J. Functional neurological disorder in the emergency department. Academic Emergency Medicine. 2021;28(6):685-696. doi:10.1111/acem.14263.
Lidstone SC, et al. Diagnosing functional neurological disorder: seeing the whole picture. CNS Spectr. 2021;26(6):593-600. doi:10.1017/S1092852920001996.
Popkirov S, Stone J, Buchan AM. Functional neurological disorder: a common and treatable stroke mimic. Stroke. 2020;51(5):1629-1635. doi:10.1161/STROKEAHA.120.029076.
