Approach to Pediatric Neurology Signs and Symptoms (paroxysmal symptoms- seizures)

In the first series of “approach to pediatric neurology signs and symptoms”, I have briefly explained about the “CELE” approach with some simple examples. I created this simple approach for following objectives;

1. to achieve a practice of confirming signs and symptoms first, before going further for investigations and medications,
2. to recognize characteristic patterns, emergency and life-threatening conditions,
3. to exclude age dependent normal variants,
4. to localize possible sites of lesions and
5. to evaluate the most possible etiologies.

I named this approach as “CELE” approach to fulfill the above objectives and representations of each word are as follow;
C – Confirmation of signs and symptoms with looking for Constellations, Characteristic features, and Clues
E – Emergency
L – Localization of site of lesion
E – Evaluation for Etiology

In this article, I am going to explain those steps of the “CELE” approach to children presenting with a variety of paroxysmal symptoms. Paroxysmal symptoms refer to a sudden onset of a neurological symptom or a cluster of symptoms, those may last over a variable time, ranging from seconds to days. And they disappear quickly and can recur at different intervals, but they are completely normal between the episodes. Examples of paroxysmal symptoms commonly seen in children are;

• Seizures
• Movement disorders
• Weakness
• Altered muscle tone
• Altered consciousness/ behavior
• Headache/ dizziness

When we consider the possible disease and conditions those can present with paroxysmal symptoms, we pay attention on common or treatable or potentially serious conditions so that necessary specific treatment can be prescribed as early as possible. Sometimes, presenting paroxysmal signs and symptoms are very vague, not severe and not always present, not disturbing the child’s activities of daily living and underlying etiology cannot be explained. In that case, if the child is otherwise normal (normal development, normal neuro-exam), that child should be just followed up without any investigations and medications. Those symptoms might go away or that will be found out as normal variants rather than pathological conditions. During the follow up period, the families should be given safety advice and reassurance.

Seizures

An epileptic seizure is defined conceptually as: “a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain.” This definition was updated by the International League Against Epilepsy (ILAE) in 2005 and was not changed in 2014 when the definition of epilepsy was updated¹.

Epilepsy exists when someone has an epileptic seizure and their brain “demonstrates a pathologic and enduring tendency to have recurrent seizures”. More specifically, epilepsy is diagnosed when an individual has:

1. at least two unprovoked or reflex seizures >24 hours apart,
2. one unprovoked or reflex seizure and a probability of having another seizure similar to the general recurrence risk after two unprovoked seizures (³60%) over the next 10 years, or

3. 3. an epilepsy syndrome¹.

Now, I am going to discuss how to approach children with possible seizures by the CELE approach.

C – Confirmation

If we look at the definitions of seizures and epilepsy, it is obvious that confirmation or diagnosis will be clinical rather than applying other investigations, such as, EEG, except for some epilepsy syndromes. Children with those paroxysmal seizures symptoms come to the doctors, but at the time of their clinic visits, they might be totally normal because of the transient nature of those symptoms. Therefore, as I mentioned in the first series, the detailed and sequential description of the events are critical, history taken from the direct witness is important and if possible, video clips of those episodes are incredibly useful.

Regarding the paroxysmal symptoms, the parents and families always complain of “possible seizures or convulsions” if they see any spells or impaired consciousness or stiffening episodes, however, the majority of them are turned out to be “seizures mimics” rather than true seizures. On the other hand, some seizure types especially in newborn and infants like subtle seizures, epileptic spasms, might not be recognized as seizures because of their special patterns different from common seizure types. Therefore, confirmation of these paroxysmal complaints and symptoms are critically important before you approach further for investigations and treatments. That will avoid unnecessary tests, drugs, other interventions, expenses and worries.

Regarding the approach to children with possible seizures, we have to follow two important steps; confirmation that it is a true seizure and what is the type of seizure.

Features such as altered mental status, eyes opened, eyes and head deviation, tongue bite, tonic/clonic movements, incontinence are suggestive of seizures. On the other hand, seizure mimics such as other causes of paroxysmal symptoms (table-1) and febrile seizure mimics (chills & rigors, febrile myoclonus, transient confusion state due to high fever) should be excluded. Diagnosis of seizure mimics again depends on the pattern of movement or posture and age of the child.

Table 1. seizure mimics

AMS-altered mental status; GOR-gastro-oesophageal reflux; IEM-inborn error of metabolism; OMA-oculomotor apraxia; PLMD-periodic limbs movement disorder; PNES-psychogenic non-epileptic seizures; PTUG – Paroxysmal tonic up gaze; RLS-restless legs syndrome; TIA-transient ischaemic attack;

After the confirmation of seizures, the next step will be to classify the seizure types. we must be familiar with types of seizures theoretically and practically. The new ILAE classification of seizures types has both a basic and expanded version, depending upon the needs and expertise of the individual utilizing the classification. The basic version (figure 1) is a contracted form of the expanded version. The expectation is the basic version will be more useful for doctors in general practice, pediatricians, non-neurologists and general neurologists, nurses and health care workers, while the expanded version will aid epileptologists/neurophysiologists and researchers².

Fig 2. ILAE 2017 Classification of Seizure Types Expanded Version

If we look at the seizure types classification, the pattern or semiology at the onset, whether focal or generalized and motor or non-motor features, is critical not only for classification, but also for management purposes.

E – Emergency

Status epilepticus (SE) and non-convulsive status epilepticus (NCSE) need to be recognized as early as possible, as an emergency assessment in children presenting with seizures. Status epilepticus (SE) is a medical emergency associated with significant morbidity and mortality. SE is traditionally defined as a continuous seizure lasting more than 30 min, or two or more seizures without full recovery of consciousness between any of them. Based on recent understanding of the pathophysiology, it is now considered that any seizure that lasts more than 5 min probably needs to be treated as SE in order to avoid the refractory state. Early treatment of SE with benzodiazepines, followed, if necessary, by second line intravenous medication such as phenobarbital, phenytoin, valproate, levetiracetam, etc. is the most widely followed strategy³.

If SE presents without prominent motor symptoms, it is called NCSE and presentations include coma, altered mental status, prolonged absence seizure, etc. Most seizures in critical ill children in intensive care unit are non-convulsive, and some patients may develop non-convulsive status epilepticus (NCSE). Those children with NCSE may have subtle signs such as eyeball movements or deviation, muscle twitching. Since it lacks the motor component, clinical diagnosis is difficult, so, high index of suspicion should be there to diagnose NCSE early and effectively. NCSE can be confirmed by EEG, but if clinically suspected, treatment (the same treatment as SE) should be considered, especially in areas where EEG is not available⁴.

Early diagnosis and effective management of both SE and NCSE are important to prevent mortality and long-term morbidity.

L – Localization

If seizure is confirmed and not in emergency, we have to localize the possible seizure focus.
Localization includes two steps; firstly, to assess whether focal or generalized at the onset of seizures and secondly to check which features (motor/ non-motor/visual) are dominant. Knowing the focal onset will suggest structural etiology and dominant features will suggest the brain lobe or region involved;

• motor activities dominant – frontal, central, frontoparietal
• aura, automatism, autonomic features with less motor activities  – temporal, temporoparietal,
• visual symptoms – occipital

E – Evaluation for underlying condition and Etiology

After the above steps of confirmation, emergency assessment and localization, the next step will be to find out the underlying conditions and diseases. This will depend on whether the seizure is a first or recurrent attack and what about associated signs and symptoms.

If it is the first or recent attack, possible conditions will be;

• febrile seizure/ convulsion – this is a benign condition and mostly no work up needed
• acute symptomatic seizure – assess & treat underlying cause such as acute CNS infection, stroke, electrolyte abnormalities, etc.
• first unprovoked seizure – manage individually, not everyone needs work up

if attacks are recurrent, possible conditions will be;

• febrile seizures
• epilepsy – needs long term anti-seizure medication (previously called anti-epileptic drugs)
• progressive symptomatic seizures due to infection, space occupying lesions, metabolic disorders – need more work-up and specific treatment, as well as anti-seizure medication

Conclusion

Seizures and seizure-mimics are common in children and our day-to-day medical practice. On the other hand, many doctors are reluctant to handle and manage those children because of lack of both theoretical and practical experience and also potentially serious conditions. I believe the above explanation of how to approach such children will encourage our medical professionals to manage such conditions more confidently. I summarized the above step by step approach in the following algorithm.

References

1. Falco-Walter JJ, Scheffer IE, Fisher RS. 2017 “The new definition and classification of seizures and epilepsy.” Epilepsy Res. 2018 Jan;139:73-79. doi: 10.1016/j. eplepsyres. 2017.11.015. Epub. PMID: 29197668.
2. Scheffer IE, Berkovic S, Capovilla G, Connolly MB, French J, Guilhoto L, Hirsch E, Jain S, Mathern GW, Moshé SL, Nordli DR, Perucca E, Tomson T, Wiebe S, Zhang YH, Zuberi SM. 2017. “ILAE classification of the epilepsies: Position paper of the ILAE Commission for Classification and Terminology. Epilepsia”. 2017 Apr;58(4):512-521. doi: 10.1111/epi.13709. Epub.PMID: 28276062; PMCID: PMC5386840.
3. Cherian A, Thomas SV. 2009. “Status epilepticus. Ann Indian Acad Neurol.” (3):140-53. doi: 10.4103/0972-2327.56312. PMID: 20174493; PMCID: PMC2824929.
4. Trinka E, Cock H, Hesdorffer D, Rossetti AO, Scheffer IE, Shinnar S, Shorvon S, Lowenstein DH. 2015. “A definition and classification of status epilepticus–Report of the ILAE Task Force on Classification of Status Epilepticus.” Epilepsia. 56(10):1515-23. doi: 10.1111/epi.13121. Epub 2015 Sep 4. PMID: 26336950.

Author Information

Kyaw Linn
Professor, Paediatric Neurology