Medical School · Year 3 · Pediatrics · includes a quiz and discussion video

Seminar 08: Pediatric Neurology

Year 3: Pediatrics Clerkship

Learning Objectives

By the end of this seminar, students will be able to:

1. Perform the pediatric neurological examination
2. Evaluate and manage seizures and epilepsy
3. Recognize febrile seizures
4. Describe common headache disorders
5. Identify neurodevelopmental disorders
6. Recognize neurological emergencies

Lecture Outline

I. Pediatric Neurological Examination

The mental status assessment in pediatrics must be adapted to the child's developmental stage, as standard adult assessments cannot be directly applied to young children. In infants, mental status is evaluated through alertness to surroundings, visual tracking and fixation on faces, quality of cry including strength and consolability, and appropriate interaction with caregivers including social smile. Toddlers should be assessed for their ability to follow simple commands, recognize familiar people and objects, and engage in age-appropriate play, while observation of language development provides additional information about cognitive function. School-age children and adolescents can participate in more formal assessments including orientation to person, place, and time, attention and concentration tasks, short-term memory, and fund of knowledge appropriate for educational level.

Cranial nerve examination in children requires creative adaptations to elicit cooperation and meaningful responses. Visual fields and tracking can be assessed using bright, interesting objects, while pupillary responses and extraocular movements generally can be tested directly with appropriate distraction and patience. The trigeminal nerve is assessed through observation of facial sensation, noting response to light touch, and evaluating sucking strength in infants, while the facial nerve is tested by observing symmetry during crying, smiling, and other spontaneous facial expressions. Hearing assessment (CN VIII) uses observation of response to sound and formal audiometry when indicated, while lower cranial nerves are evaluated through observation of swallowing, gag reflex, and tongue movements.

Motor and sensory examination provides critical information about localization of neurological lesions. Tone assessment includes both passive range of motion and observation of active movements, with hypertonia suggesting upper motor neuron lesions or cerebral palsy and hypotonia occurring in neuromuscular disorders or central nervous system dysfunction. Strength testing in infants relies on observation of spontaneous movements and resistance to gravity, while older children can participate in formal manual muscle testing. Deep tendon reflexes are elicited using standard techniques, with primitive reflexes (Moro, grasp, asymmetric tonic neck reflex) assessed in infants and expected to resolve by specific ages. Coordination is assessed through observation of reaching, finger-to-nose testing, and gait evaluation in ambulatory children.

Red flags in the pediatric neurological examination warrant urgent evaluation and often imaging. Asymmetry of motor function, strength, or reflexes suggests focal central nervous system pathology including stroke, tumor, or malformation. Hypotonia in an infant with weakness may indicate neuromuscular disease such as spinal muscular atrophy or hypoxic-ischemic encephalopathy. Progressive hypertonia, particularly in a child who was previously developing normally, raises concern for cerebral palsy or progressive neurological disease. Regression of developmental milestones, where a child loses previously acquired skills, represents a red flag for neurodegenerative disease, metabolic disorders, or structural lesions requiring comprehensive evaluation. Bulging fontanelle or rapidly increasing head circumference indicates increased intracranial pressure requiring urgent imaging.

<image>Panel A: Age-appropriate mental status assessment techniques showing evaluation of alertness, interaction, and cognition from infancy through adolescence with expected findings at each developmental stage. Panel B: Cranial nerve examination techniques adapted for pediatric patients demonstrating methods for assessing visual tracking, facial symmetry, hearing response, and swallowing in children of different ages. Panel C: Motor examination showing tone assessment in infants including pull-to-sit maneuver, ventral suspension, and primitive reflex testing with normal and abnormal findings. Panel D: Red flag neurological findings requiring urgent evaluation including asymmetry, hypotonia patterns, regression, and signs of increased intracranial pressure with recommended imaging approach.</image>

II. Seizures - Classification

Generalized seizures originate simultaneously in bilateral cerebral networks and include several distinct clinical types with different manifestations and treatment implications. Tonic-clonic seizures (formerly grand mal) begin with sudden loss of consciousness, followed by a tonic phase of generalized muscle stiffening lasting 10-20 seconds, then a clonic phase of rhythmic jerking lasting 1-2 minutes, with prolonged postictal confusion and fatigue. Absence seizures (formerly petit mal) present as brief episodes of behavioral arrest with staring and unresponsiveness lasting 5-30 seconds, without significant motor manifestations or postictal period, and may occur dozens of times daily. Myoclonic seizures consist of sudden, brief, shock-like muscle jerks affecting one or multiple muscle groups, while atonic seizures cause sudden loss of muscle tone resulting in drop attacks with high injury risk.

Focal seizures originate in a specific region of one cerebral hemisphere and may remain localized or spread to involve the entire brain. Focal seizures with preserved awareness (formerly simple partial) produce symptoms corresponding to the affected brain region including motor movements, sensory symptoms, or autonomic changes without alteration of consciousness. Focal seizures with impaired awareness (formerly complex partial) involve altered consciousness with behavioral arrest, staring, and automatisms such as lip smacking, chewing, or hand movements, followed by postictal confusion. Focal to bilateral tonic-clonic seizures begin as focal events with an aura or focal symptoms before generalizing, and identification of focal onset has important implications for treatment selection and potential surgical candidacy.

The classification of seizures with unknown onset recognizes that not all seizures can be immediately categorized based on available information. Epileptic spasms, characteristic of infantile spasms syndrome, consist of brief flexor or extensor contractions often occurring in clusters, typically beginning between 3-12 months of age and associated with poor developmental outcomes if not promptly recognized and treated. When insufficient information exists to classify a seizure as generalized or focal, it remains unclassified pending additional clinical data or EEG findings, with treatment initiated based on the clinical presentation while further evaluation continues.

Distinguishing provoked from unprovoked seizures has critical implications for recurrence risk, diagnostic evaluation, and treatment decisions. Provoked or acute symptomatic seizures occur in the setting of acute precipitants including fever in febrile seizures, electrolyte abnormalities such as hyponatremia or hypoglycemia, head trauma, or central nervous system infection, and generally have lower recurrence risk once the precipitant resolves. Unprovoked seizures occur without identifiable acute trigger and carry higher recurrence risk, with epilepsy diagnosed after two or more unprovoked seizures occurring more than 24 hours apart or after a single unprovoked seizure with additional risk factors including abnormal EEG or structural brain abnormality predicting high recurrence probability.

<image>Panel A: Generalized seizure types illustrated showing tonic-clonic progression with EEG correlation, absence seizure with 3 Hz spike-wave pattern, myoclonic jerks, and atonic drop attack with clinical features of each. Panel B: Focal seizure classification demonstrating seizure origin in one hemisphere, propagation patterns, aura manifestations based on cortical location, and progression to focal to bilateral tonic-clonic seizure. Panel C: Epileptic spasms in infantile spasms syndrome showing flexor spasm posture, clustering pattern, hypsarrhythmia EEG pattern, and developmental regression timeline. Panel D: Comparison of provoked versus unprovoked seizures with common precipitants, recurrence risk percentages, and criteria for epilepsy diagnosis.</image>

III. Seizure Evaluation

Evaluation of a first unprovoked seizure requires comprehensive history, examination, and selected diagnostic testing to determine recurrence risk and guide management. Detailed seizure description from witnesses should characterize the event onset including any focal features or aura, nature of motor activity, duration, level of consciousness, and postictal period characteristics. Neurological examination seeks focal abnormalities suggesting underlying structural lesion, and family history of seizures or epilepsy informs both diagnosis and genetic counseling. Laboratory evaluation depends on clinical context but may include glucose measurement, comprehensive metabolic panel for electrolyte assessment, and in young children or ill-appearing patients, consideration of lumbar puncture to evaluate for meningitis or encephalitis.

Electroencephalography plays a central role in seizure evaluation, providing information about seizure type, epilepsy syndrome, and recurrence risk. Routine EEG should be performed in all patients after a first unprovoked seizure, ideally within 24-48 hours when yield is highest, with sleep deprivation before the study increasing sensitivity for detecting epileptiform abnormalities. Epileptiform discharges including spikes, sharp waves, and spike-wave complexes indicate cortical irritability and increase predicted recurrence risk, while specific patterns suggest particular epilepsy syndromes such as 3 Hz spike-wave in childhood absence epilepsy or hypsarrhythmia in infantile spasms. A normal EEG does not exclude epilepsy, as interictal epileptiform discharges may not be present during a single routine study, and prolonged ambulatory EEG or video-EEG monitoring may be needed in selected cases.

Neuroimaging determines whether structural brain abnormalities underlie the seizure disorder and should be considered in all patients with new-onset unprovoked seizures. MRI with dedicated epilepsy protocol provides highest sensitivity for detecting subtle cortical malformations, hippocampal sclerosis, tumors, and vascular malformations, and should be performed in patients with focal seizures, focal EEG abnormalities, or focal neurological findings. CT scan provides rapid evaluation when urgent neuroimaging is needed, such as after head trauma or when intracranial hemorrhage is suspected, but has lower sensitivity than MRI for most epileptogenic lesions. Imaging may be deferred in children with classic features of benign epilepsy syndromes such as childhood absence epilepsy or self-limited epilepsy with centrotemporal spikes.

Recurrence risk after a first unprovoked seizure guides decisions about initiating antiseizure medication versus observation. Overall recurrence risk after a single unprovoked seizure is approximately 40-50% within 2 years, with highest risk in the first 6 months. Risk factors for recurrence include abnormal EEG with epileptiform discharges, abnormal MRI with structural lesion, remote symptomatic etiology such as previous stroke or traumatic brain injury, seizure occurring during sleep, and neurological abnormalities on examination. Current practice generally reserves antiseizure medication initiation for patients with high recurrence risk features or after a second unprovoked seizure, as medication reduces recurrence but has not been shown to alter long-term prognosis, and approximately half of children with a single seizure never have another.

<image>Panel A: First unprovoked seizure evaluation algorithm showing history elements to obtain, physical examination focus, laboratory testing indications, and decision points for EEG and imaging. Panel B: EEG findings in common epilepsy syndromes displaying 3 Hz spike-wave of absence epilepsy, centrotemporal spikes of self-limited childhood epilepsy, and focal epileptiform discharges with localization significance. Panel C: MRI epilepsy protocol showing sequences and findings including hippocampal sclerosis, cortical dysplasia, and mesial temporal sclerosis with imaging examples. Panel D: Recurrence risk stratification showing low, intermediate, and high risk categories with corresponding risk factors and recommended management approach for each.</image>

IV. Epilepsy Syndromes

Childhood absence epilepsy represents one of the most common and most treatable pediatric epilepsy syndromes, typically presenting between ages 4-10 years. Seizures consist of brief staring spells lasting 5-30 seconds, characterized by sudden onset and offset without warning or postictal period, often with subtle eyelid fluttering or lip movements. Episodes may occur tens to hundreds of times daily, frequently mistaken for daydreaming until their stereotypical nature and frequency become apparent, and can be reliably provoked by hyperventilation during EEG. The characteristic EEG pattern shows bilateral synchronous 3 Hz spike-wave discharges that begin and end abruptly, correlating with clinical absence episodes. Ethosuximide is first-line treatment for pure absence epilepsy, while valproate or lamotrigine is preferred if generalized tonic-clonic seizures also occur.

Juvenile myoclonic epilepsy is the most common generalized epilepsy syndrome, typically presenting in adolescence with a characteristic triad of seizure types. Myoclonic jerks, typically affecting the arms and occurring shortly after awakening, are the hallmark and are often initially dismissed as clumsiness before their significance is recognized. Generalized tonic-clonic seizures occur in most patients, often triggered by sleep deprivation, alcohol, or stress, and may be the presenting seizure type that prompts medical evaluation. Absence seizures occur in approximately one-third of patients, adding to the seizure burden. EEG shows 4-6 Hz polyspike-wave discharges, often with photosensitivity. JME responds well to broad-spectrum antiseizure medications including valproate and levetiracetam, but typically requires lifelong treatment as seizures usually recur when medication is withdrawn.

Infantile spasms syndrome (West syndrome) represents a severe epileptic encephalopathy requiring urgent recognition and treatment. Spasms consist of sudden brief contractions, either in flexion (head drop, arm flexion, leg flexion) or extension, typically occurring in clusters upon awakening, beginning between 3-12 months of age. The characteristic EEG pattern, hypsarrhythmia, shows high-amplitude chaotic activity with multifocal spikes and absence of normal background organization. Underlying etiologies include structural brain abnormalities, genetic conditions including tuberous sclerosis, and metabolic disorders, though approximately 10-20% are cryptogenic. Treatment with ACTH or vigabatrin (preferred for tuberous sclerosis) should be initiated urgently to control spasms and preserve neurodevelopment, though prognosis depends heavily on underlying etiology.

Lennox-Gastaut syndrome represents another severe epileptic encephalopathy characterized by multiple seizure types, cognitive impairment, and characteristic EEG findings. Onset typically occurs between 1-8 years, sometimes evolving from infantile spasms, with seizures including tonic (especially during sleep), atonic (causing drop attacks), atypical absence, and myoclonic types. The EEG shows slow spike-wave complexes at less than 2.5 Hz during waking and paroxysmal fast activity during sleep. Cognitive impairment is universal and often progressive, significantly impacting quality of life for patients and families. Treatment is challenging, typically requiring multiple antiseizure medications and sometimes dietary therapy (ketogenic diet) or surgical options (corpus callosotomy for drop attacks), and seizures remain medically refractory in most patients.

<image>Panel A: Childhood absence epilepsy showing age of onset range, typical absence seizure features, 3 Hz spike-wave EEG pattern during hyperventilation, and treatment algorithm with ethosuximide first-line. Panel B: Juvenile myoclonic epilepsy demonstrating the triad of myoclonic jerks upon awakening, generalized tonic-clonic seizures, and absence seizures with polyspike-wave EEG and trigger factors. Panel C: Infantile spasms syndrome showing flexor spasm posture, clustering pattern, hypsarrhythmia EEG, and urgent treatment protocol with ACTH and vigabatrin. Panel D: Lennox-Gastaut syndrome features including multiple seizure types, slow spike-wave EEG, cognitive impairment progression, and multimodal treatment approach.</image>

V. Antiseizure Medications

Broad-spectrum antiseizure medications effectively treat multiple seizure types including both focal and generalized seizures, making them appropriate first-line choices when seizure classification is uncertain. Levetiracetam has become one of the most commonly prescribed antiseizure medications due to its broad efficacy, favorable side effect profile, lack of significant drug interactions, and availability of intravenous formulation for acute use. Valproate provides excellent efficacy for generalized epilepsies including absence, myoclonic, and tonic-clonic seizures, though its use is limited by teratogenicity in women of childbearing potential, weight gain, and rare but serious hepatotoxicity risk in young children. Lamotrigine offers broad-spectrum efficacy with generally good tolerability but requires slow titration to avoid Stevens-Johnson syndrome, particularly when used with valproate which increases lamotrigine levels. Topiramate and zonisamide provide additional broad-spectrum options with varying side effect profiles.

Narrow-spectrum antiseizure medications effectively treat specific seizure types but may worsen others, making accurate seizure classification essential before their use. Ethosuximide is highly effective for absence seizures but has no efficacy against other seizure types, making it ideal for pure childhood absence epilepsy but requiring combination therapy if tonic-clonic seizures also occur. Carbamazepine and oxcarbazepine effectively treat focal seizures and focal to bilateral tonic-clonic seizures but may exacerbate generalized epilepsies including absence, myoclonic, and atonic seizures. Phenobarbital remains useful for neonatal seizures and status epilepticus but is less commonly used for chronic epilepsy treatment due to cognitive effects, though it remains important in resource-limited settings.

Side effects of antiseizure medications require monitoring and may influence medication selection and adherence. Valproate causes weight gain, tremor, hair thinning, and elevation of liver enzymes, with rare but potentially fatal hepatotoxicity primarily affecting children under 2 years on polytherapy. Carbamazepine causes rash in 5-10% of patients, with rare progression to Stevens-Johnson syndrome or toxic epidermal necrolysis, and causes hyponatremia through SIADH-like effect. Lamotrigine causes rash that may progress to Stevens-Johnson syndrome, with risk highest during rapid titration and concurrent valproate use. Topiramate causes cognitive slowing described as word-finding difficulty and slowed processing, kidney stones, and oligohidrosis with heat intolerance. Levetiracetam is generally well-tolerated but causes behavioral changes including irritability and aggression in a subset of patients.

Monitoring during antiseizure medication therapy includes clinical assessment and selected laboratory testing. Drug levels guide dosing for medications with established therapeutic ranges including phenytoin, carbamazepine, and valproate, though clinical response ultimately determines adequacy of therapy. Complete blood count and comprehensive metabolic panel should be checked at baseline and periodically for medications with hematologic or hepatic effects, with more frequent monitoring during initiation and in high-risk populations. Sodium levels require monitoring with carbamazepine and oxcarbazepine given the hyponatremia risk. Clinical monitoring for breakthrough seizures, side effects, and adherence occurs at each visit, with medication adjustments guided by clinical response rather than drug levels alone.

<image>Panel A: Broad-spectrum antiseizure medications comparison showing levetiracetam, valproate, lamotrigine, and topiramate with efficacy spectrum, key side effects, and dosing considerations. Panel B: Narrow-spectrum medications showing ethosuximide for absence, carbamazepine for focal seizures, and phenobarbital for neonatal use with warnings about seizure type worsening. Panel C: Common side effects by medication displayed as clinical symptoms with management strategies including dose adjustment, medication change, and monitoring requirements. Panel D: Monitoring protocol showing baseline and follow-up laboratory testing, clinical assessment elements, and drug level interpretation with therapeutic ranges.</image>

VI. Febrile Seizures

Febrile seizures occur in children aged 6 months to 5 years in association with fever without evidence of intracranial infection or other defined cause, representing the most common seizure type in childhood with 2-5% prevalence. Simple febrile seizures are generalized tonic-clonic events lasting less than 15 minutes, occurring once within a 24-hour period, in a neurologically normal child, and have an excellent prognosis with no increased risk of epilepsy. Complex febrile seizures have features suggesting higher risk: focal onset, duration greater than 15 minutes, or recurrence within 24 hours, and warrant more thorough evaluation. The seizure typically occurs during temperature rise rather than at peak temperature, often bringing the illness to attention, and there is strong genetic predisposition with family history present in many cases.

Evaluation of febrile seizures focuses on identifying the source of fever and excluding meningitis rather than extensive seizure workup. History should characterize the seizure, assess for meningeal signs, and identify the focus of infection, which is most commonly viral upper respiratory infection, otitis media, or viral gastroenteritis. Lumbar puncture is indicated if meningitis is clinically suspected based on meningeal signs, prolonged postictal period, or concerning clinical appearance, and should be strongly considered in infants under 6 months or under 12 months who have not received conjugate vaccines. Laboratory testing is guided by clinical presentation and is not routinely needed for simple febrile seizures in well-appearing children with identified infection source. Neuroimaging is not indicated for simple febrile seizures and should be reserved for complex seizures with focal features or persistently abnormal neurological examination.

Risk factors for recurrence help counsel families about likelihood of additional febrile seizures. Overall recurrence risk after a first febrile seizure is approximately 30%, with most recurrences occurring within one year. Risk factors for recurrence include younger age at first seizure (particularly under 12 months), lower temperature at time of seizure, shorter duration of fever before seizure, and family history of febrile seizures. Children with multiple risk factors may have recurrence rates exceeding 50%, while those without risk factors have lower recurrence rates. Despite recurrence, simple febrile seizures do not increase epilepsy risk above the general population rate of approximately 1%.

Management of febrile seizures emphasizes supportive care, parental education, and reassurance rather than preventive medication. Acute seizures require standard first aid including positioning for safety, avoiding placing anything in the mouth, and timing the seizure, with rescue benzodiazepine (rectal diazepam or intranasal midazolam) provided for future use if seizures are prolonged. Daily prophylactic antiseizure medications are not recommended for simple febrile seizures as risks outweigh benefits and medications do not prevent epilepsy development. Intermittent prophylaxis with oral diazepam during febrile illnesses reduces recurrence risk but causes significant sedation that may mask signs of serious illness and is generally not recommended. Parent education addresses seizure first aid, the benign prognosis, the difference between febrile seizures and epilepsy, and when to seek medical attention.

<image>Panel A: Febrile seizure classification comparing simple versus complex features including duration, focality, recurrence within 24 hours, and corresponding evaluation approach for each. Panel B: Decision algorithm for lumbar puncture in febrile seizures showing age-based considerations, meningeal signs assessment, vaccination status, and clinical appearance factors. Panel C: Recurrence risk factors displayed with corresponding risk percentages showing age at first seizure, temperature threshold, fever duration, and family history contributions. Panel D: Parent education content showing seizure first aid steps, when to call 911, prognosis information, and appropriate fever management without preventing seizures.</image>

VII. Headaches

Primary headache disorders including migraine and tension-type headache represent the most common headache diagnoses in children and adolescents, with migraine alone affecting 5-10% of children. Migraine in children differs from adult migraine in several important ways: attacks are often shorter, lasting 1-72 hours rather than 4-72 hours; pain is frequently bilateral rather than unilateral; and accompanying symptoms including nausea, vomiting, photophobia, and phonophobia may be more prominent than head pain itself. Family history is common, and children with migraine often have motion sickness and episodic abdominal pain (abdominal migraine). Tension-type headache produces mild to moderate bilateral pressure or tightening sensation without significant associated symptoms, lasting 30 minutes to several days, and typically does not prevent normal activities.

Migraine presentation in children requires recognition of age-specific features for accurate diagnosis. Aura occurs in approximately 15-30% of pediatric migraine, most commonly visual (scintillating scotoma, visual disturbance), but may include sensory symptoms (paresthesias) or rarely motor weakness (hemiplegic migraine). Premonitory symptoms including mood changes, food cravings, and yawning may precede headache by hours. Common triggers include stress, sleep disturbance (either deprivation or excess), skipping meals, certain foods, and menstruation in adolescent girls. Menstrual migraine, occurring in relation to menses, often proves more severe and treatment-resistant than non-menstrual attacks. The impact of migraine on school attendance, social activities, and quality of life may be substantial and requires attention beyond pain management.

Red flags in headache evaluation indicate potential secondary headache requiring urgent evaluation. "Worst headache of life" or thunderclap onset suggests subarachnoid hemorrhage until proven otherwise, requiring urgent CT and lumbar puncture if CT is negative. Progressive or worsening headaches over weeks to months, particularly with papilledema on funduscopic examination, raise concern for increased intracranial pressure from tumor, hydrocephalus, or idiopathic intracranial hypertension. Headaches that wake the child from sleep or are worse in the morning and improve throughout the day suggest increased intracranial pressure. Focal neurological signs including weakness, ataxia, visual field deficits, or cranial nerve palsies require neuroimaging to exclude structural lesion. Headache following trauma, particularly with altered consciousness or focal findings, requires evaluation for intracranial hemorrhage.

Treatment of pediatric migraine includes both acute and preventive strategies. Acute treatment should be administered early in the attack for best efficacy, with NSAIDs (ibuprofen) serving as first-line therapy and triptans (sumatriptan, rizatriptan, almotriptan) approved for adolescents and increasingly used in younger children. Rest in a dark, quiet room complements pharmacotherapy, and adequate hydration and regular meals help prevent attacks. Preventive medication is considered when attacks occur frequently (generally more than 4 per month), cause significant disability, or respond poorly to acute treatment, with options including cyproheptadine (especially in young children), amitriptyline, propranolol, and topiramate. Lifestyle modification addressing sleep hygiene, regular meals, stress management, and trigger avoidance forms the foundation of preventive therapy regardless of medication use.

<image>Panel A: Pediatric migraine features compared to adult migraine showing differences in duration, location, associated symptoms, and common triggers with age-specific presentation characteristics. Panel B: Migraine aura types illustrated showing visual aura (scintillating scotoma, visual disturbance), sensory aura (spreading paresthesias), and premonitory symptoms timeline. Panel C: Headache red flags displayed with corresponding concerning diagnoses including worst headache ever (SAH), progressive with papilledema (increased ICP), morning predominance (tumor), and focal signs (structural lesion). Panel D: Migraine treatment algorithm showing acute therapy with NSAIDs and triptans, preventive medication indications and options, and lifestyle modification components.</image>

VIII. Neurodevelopmental Disorders

Cerebral palsy encompasses a group of permanent disorders of movement and posture caused by non-progressive disturbances occurring in the developing fetal or infant brain, representing the most common motor disability in childhood. The motor disorders are often accompanied by disturbances of sensation, perception, cognition, communication, and behavior, as well as secondary musculoskeletal problems. Classification by motor type includes spastic (most common at 70-80%), dyskinetic (including dystonic and choreoathetoid), ataxic, and mixed forms, while topographic classification describes the body regions affected: hemiplegia (one side), diplegia (legs more than arms), and quadriplegia (all four limbs equally). Risk factors include prematurity, low birth weight, perinatal hypoxia-ischemia, intrauterine infections, and multiple gestation.

Autism spectrum disorder is a neurodevelopmental condition characterized by persistent deficits in social communication and interaction across multiple contexts, along with restricted, repetitive patterns of behavior, interests, or activities. Social communication deficits include impaired social-emotional reciprocity, reduced sharing of interests and emotions, deficits in nonverbal communication including poor eye contact and limited gestures, and difficulty developing and maintaining relationships. Restricted and repetitive behaviors include stereotyped motor movements or use of objects, insistence on sameness, highly restricted interests, and hyper- or hyporeactivity to sensory input. Symptoms must be present in early childhood, though they may not become fully apparent until social demands exceed capacity, and the diagnosis requires that symptoms cause clinically significant impairment.

Attention-deficit/hyperactivity disorder is characterized by a persistent pattern of inattention and/or hyperactivity-impulsivity that interferes with functioning or development. Inattention symptoms include difficulty sustaining attention, failing to follow through on tasks, difficulty organizing, avoiding sustained mental effort, losing things, being easily distracted, and forgetfulness in daily activities. Hyperactivity-impulsivity symptoms include fidgeting, leaving seat when expected to remain seated, running or climbing inappropriately, inability to play quietly, being "on the go," talking excessively, blurting out answers, difficulty waiting turn, and interrupting others. Diagnosis requires six or more symptoms (five in older adolescents and adults) in either or both domains, present before age 12, occurring in two or more settings, and causing significant impairment.

Intellectual disability involves deficits in intellectual functions and adaptive functioning with onset during the developmental period. Intellectual functions include reasoning, problem-solving, planning, abstract thinking, judgment, academic learning, and learning from experience, assessed by clinical evaluation and standardized intelligence testing showing IQ approximately two standard deviations below the mean. Adaptive functioning deficits limit independence and social responsibility compared to developmental and sociocultural standards, affecting conceptual (academic), social, and practical domains. Severity is determined by adaptive functioning rather than IQ score, ranging from mild (may achieve academic skills to approximately sixth-grade level, can live independently with support) through moderate, severe, and profound (requiring extensive support for daily activities).

<image>Panel A: Cerebral palsy classification showing motor types (spastic, dyskinetic, ataxic, mixed), topographic patterns (hemiplegia, diplegia, quadriplegia), and associated impairments with risk factor timeline. Panel B: Autism spectrum disorder diagnostic criteria showing social communication deficits (reciprocity, nonverbal communication, relationships) and restricted/repetitive behaviors (stereotypies, sameness, restricted interests, sensory) with severity levels. Panel C: ADHD symptom domains displaying inattention symptoms, hyperactivity symptoms, and impulsivity symptoms with DSM-5 diagnostic criteria including age, settings, and impairment requirements. Panel D: Intellectual disability severity levels showing adaptive functioning domains (conceptual, social, practical), expected independence levels, and support requirements for mild through profound categories.</image>

IX. Neurological Emergencies

Status epilepticus is defined as a seizure lasting more than 5 minutes or two or more seizures without return to baseline between them, representing a medical emergency requiring immediate intervention to prevent neurological injury and death. The treatment protocol follows a staged approach: initial management secures airway, provides oxygen, establishes vascular access, and checks glucose; first-line treatment is benzodiazepine (lorazepam 0.1 mg/kg IV or diazepam 0.2 mg/kg IV/0.5 mg/kg rectal), which may be repeated once in 5 minutes if seizure continues. Second-line treatment at 10-20 minutes includes fosphenytoin (20 PE/kg), levetiracetam (60 mg/kg), or valproate (40 mg/kg), chosen based on patient factors and institutional protocols. Refractory status epilepticus continuing beyond 40-60 minutes despite first and second-line agents requires anesthetic doses of midazolam, propofol, or pentobarbital with continuous EEG monitoring.

Acute weakness in children requires urgent evaluation to distinguish central from peripheral causes and identify treatable emergencies. Guillain-Barre syndrome presents with ascending symmetric weakness, areflexia, and sensory symptoms typically following a viral illness or Campylobacter infection, with respiratory failure risk requiring close monitoring of vital capacity. Transverse myelitis causes rapid-onset weakness, sensory level, and bowel/bladder dysfunction from spinal cord inflammation, requiring MRI and possible treatment with high-dose corticosteroids. Botulism presents with descending weakness beginning with cranial nerve dysfunction (ptosis, weak cry, poor feeding), hypotonia, constipation, and potentially respiratory failure in infants exposed to spores (often from honey). Myasthenia gravis causes fatigable weakness, particularly affecting ocular muscles (ptosis, diplopia), with diagnosis confirmed by acetylcholine receptor antibodies and response to acetylcholinesterase inhibitors.

Increased intracranial pressure may result from mass lesions, hydrocephalus, cerebral edema, or idiopathic intracranial hypertension, and requires prompt recognition and management to prevent herniation. Signs and symptoms include headache (often worse when recumbent), vomiting (often without nausea), papilledema, sixth nerve palsy causing diplopia, and in infants, bulging fontanelle and suture splitting. Cushing's triad of bradycardia, hypertension, and irregular respirations represents a late finding indicating imminent herniation. Herniation syndromes produce characteristic findings: uncal herniation causes ipsilateral pupil dilation and contralateral hemiparesis; central herniation causes bilateral pupil changes and posturing. Emergency management includes head elevation to 30 degrees, maintenance of normothermia, hyperventilation to PCO2 of 30-35 mmHg (temporary measure), and hyperosmolar therapy with mannitol or hypertonic saline.

Pediatric stroke, though less common than in adults, occurs and requires recognition for timely intervention. Risk factors differ from adults and include congenital heart disease, sickle cell disease, moyamoya disease, prothrombotic conditions, and arterial dissection. Presentation includes sudden onset focal neurological deficits such as hemiparesis, aphasia, visual field cuts, or ataxia, but may also present with seizures or altered consciousness, particularly in young children. Imaging evaluation includes CT to exclude hemorrhage followed by MRI with diffusion-weighted imaging to confirm acute ischemia, along with vascular imaging (MRA or CTA) to evaluate for arteriopathy. Management focuses on supportive care, treatment of underlying conditions (such as exchange transfusion for sickle cell), and consideration of thrombolysis in selected cases with appropriate expertise and timing.

<image>Panel A: Status epilepticus treatment protocol showing staged approach with first-line benzodiazepines, second-line agents (fosphenytoin, levetiracetam, valproate), and refractory status management with timeline and dosing. Panel B: Acute weakness differential showing Guillain-Barre syndrome (ascending, areflexia), transverse myelitis (sensory level, bladder), botulism (descending, cranial nerves), and myasthenia (fatigable) with distinguishing features. Panel C: Increased intracranial pressure signs and herniation syndromes showing Cushing's triad, uncal herniation with pupil findings, and central herniation with emergency management steps. Panel D: Pediatric stroke evaluation and management showing risk factors, presentation differences from adults, imaging protocol, and treatment approach based on etiology.</image>

X. Other Neurological Conditions

Tic disorders range from transient simple tics to Tourette syndrome and require appropriate classification for counseling and treatment. Simple motor tics include eye blinking, facial grimacing, shoulder shrugging, and head jerking, while complex motor tics involve more coordinated movements such as touching, hopping, or obscene gestures (copropraxia). Simple vocal tics include throat clearing, sniffing, and grunting, while complex vocal tics involve words, phrases, or rarely coprolalia (obscene speech, occurring in only 10-15% of Tourette syndrome). Transient tic disorder involves motor and/or vocal tics present for less than one year, while chronic tic disorder involves either motor or vocal tics (not both) persisting more than one year. Tourette syndrome requires both motor and vocal tics present (not necessarily concurrently) for more than one year with onset before age 18.

Hypotonia in infants requires systematic evaluation to distinguish central from peripheral causes, as the differential diagnosis and prognosis differ substantially. Central hypotonia (brain or spinal cord origin) presents with weakness but normal or increased deep tendon reflexes, often with other features including seizures, dysmorphic features, or abnormal brain imaging, and causes include hypoxic-ischemic encephalopathy, chromosomal abnormalities such as Down syndrome, and metabolic disorders. Peripheral hypotonia (nerve, neuromuscular junction, or muscle origin) presents with weakness and decreased or absent reflexes, and includes spinal muscular atrophy, congenital myopathies, congenital muscular dystrophies, and congenital myasthenic syndromes. Evaluation includes genetic testing (SMN1 gene deletion for SMA, chromosomal microarray), creatine kinase level, and potentially electrodiagnostic studies and muscle biopsy.

Spinal muscular atrophy is an autosomal recessive neurodegenerative disease caused by SMN1 gene mutations leading to motor neuron degeneration and progressive weakness. Type I (Werdnig-Hoffmann disease) presents before 6 months with severe hypotonia, weakness, tongue fasciculations, respiratory failure, and death typically before age 2 without treatment. Type II presents between 6-18 months with the ability to sit but never walk independently, moderate weakness, and scoliosis. Type III (Kugelberg-Welander disease) presents after 18 months with the ability to walk independently, progressive weakness, and relatively preserved lifespan. Disease-modifying treatments including nusinersen (antisense oligonucleotide), onasemnogene abeparvovec (gene therapy), and risdiplam (small molecule) have dramatically improved outcomes, particularly when initiated presymptomatically through newborn screening.

Duchenne muscular dystrophy is an X-linked recessive disorder caused by mutations in the dystrophin gene, affecting approximately 1 in 3,500 male births. Initial symptoms typically appear between ages 2-5 years with proximal weakness, waddling gait, difficulty climbing stairs, and frequent falls. Gowers' sign, using hands to "walk up" the thighs when rising from the floor, reflects proximal lower extremity weakness. Pseudohypertrophy of calf muscles results from fibrofatty replacement. Disease progression leads to loss of ambulation typically by age 12, scoliosis, cardiomyopathy, respiratory failure, and death in the third decade without treatment. Management includes corticosteroids (deflazacort, prednisone) which prolong ambulation and preserve respiratory function, cardiac monitoring and treatment, respiratory support, and emerging therapies including exon-skipping antisense oligonucleotides for specific mutations.

<image>Panel A: Tic disorder classification showing simple versus complex motor and vocal tics, diagnostic criteria for transient tics, chronic tics, and Tourette syndrome, and associated comorbidities (ADHD, OCD). Panel B: Hypotonia evaluation comparing central (normal reflexes, associated features) versus peripheral (decreased reflexes, weakness pattern) causes with diagnostic approach including genetic testing, CK, and EMG. Panel C: Spinal muscular atrophy types showing age of onset, motor milestones achieved, natural history, and disease-modifying treatment options with newborn screening importance. Panel D: Duchenne muscular dystrophy showing Gowers' sign, calf pseudohypertrophy, disease progression timeline, and multimodal management including corticosteroids, cardiac monitoring, and respiratory support.</image>

Summary

• Pediatric neurological examination requires age-appropriate adaptations; red flags include asymmetry, regression, and signs of increased intracranial pressure
• Seizure classification as generalized versus focal guides medication selection; provoked versus unprovoked determines recurrence risk
• First unprovoked seizure evaluation includes EEG (ideally within 24-48 hours) and consideration of MRI; treatment not always needed
• Childhood absence epilepsy presents with brief staring spells, 3 Hz spike-wave on EEG, and responds well to ethosuximide
• Infantile spasms require urgent treatment with ACTH or vigabatrin; hypsarrhythmia on EEG is characteristic
• Simple febrile seizures have excellent prognosis; complex febrile seizures warrant more thorough evaluation
• Headache red flags include worst headache ever, morning headaches with vomiting, papilledema, and focal neurological signs
• Migraine treatment includes acute therapy (NSAIDs, triptans) and preventive strategies for frequent or disabling attacks
• Status epilepticus protocol: benzodiazepine first-line, then fosphenytoin/levetiracetam/valproate, then anesthetic agents for refractory cases
• Duchenne muscular dystrophy presents with proximal weakness, Gowers' sign, and calf pseudohypertrophy; corticosteroids are standard treatment

Key Terms

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