Chapter 13. Neurology

Clinical Summary

Meningitis is inflammation of the membranes (dura, pia mater, and arachnoid) surrounding the brain and spinal cord. Bacterial meningitis most commonly results from seeding of the leptomeninges from a distant focus (hematogenous spread). It can also result from a direct extension from a contiguous focus (eg, sinusitis, otitis media, mastoiditis) or by direct invasion (eg, head trauma). Etiologies in the neonatal period include Group B streptococci, gram-negative enteric bacilli (Escherichia coli, Enterobacter spp.), and Listeria monocytogenes. Etiology from age 1 to 3 months includes Streptococcus pneumoniae, Neisseria meningitides, Haemophilus influenzae type b (Hib), and L monocytogenes. Etiology in infants >3 months include S pneumoniae, N meningitides, and Hib (unvaccinated children). In patients with ventriculoperitoneal shunts, coagulase-negative Staphylococcus epidermidis and Staphylococcus aureus are the pathogens. Tuberculous meningitis may present with a gradual onset over several weeks. Low-grade fever, weight loss, adenopathy, vomiting, lethargy, cranial nerve palsies, and coma are common presentations. Differential diagnosis includes other types of meningitis, subarachnoid hemorrhage (ruptured arteriovenous malformation [AVM]/aneurysm), parameningeal/paraspinal infection (eg, brain abscess, subdural or epidural abscess), retropharyngeal abscess, and trauma (eg, shaken impact syndrome, subdural or epidural hematoma).

Emergency Department Treatment and Disposition

Stabilize the patient and provide continuous cardiac and pulse oximetry monitoring, and fluid resuscitation with crystalloids for septic shock. If patient is not in shock, restrict intravenous (IV) fluid to basal requirement with 0.33% NaCl solution because of possible syndrome of inappropriate antidiuretic hormone (SIADH). Obtain cerebrospinal fluid (CSF) with lumbar puncture (LP). Head CT scan is not required routinely before LP when there is a clinical diagnosis of uncomplicated meningitis. If focal neurologic signs are present (eg, suspected complications like subdural effusion or empyema) or there is papilledema, begin antibiotics and obtain a CT scan before performing LP. Antigen detection tests (eg, latex agglutination) may help in partially treated meningitis. Order India ink stain for immunocompromised patients, and acid-fast stain when tuberculous meningitis is suspected. Order complete blood count, blood culture, serum electrolytes (monitoring for SIADH), glucose, and coagulation profile (disseminated intravascular coagulation). Place a 5–tuberculin unit purified protein derivative tuberculin test on the forearm of all patients with meningitis in areas where tuberculosis is endemic. Treat patients <4 weeks of age empirically with ampicillin and cefotaxime or ampicillin and an aminoglycoside (eg, gentamicin). Consider antiviral therapy if herpes is suspected. Treat patients >4 weeks of age empirically with vancomycin and cefotaxime or ceftriaxone. Offer antibiotic prophylaxis to close contacts for exposure to Hib and N meningitides. Dexamethasone (if given before or concurrently with the first dose of antibiotics) may help decrease hearing loss associated with Hib meningitis. Admit patients with a clinical diagnosis; admit those with septic shock requiring resuscitation to the ICU. Use standard and droplet precautions for the first 24 hours after institution of appropriate antibiotics.

Pearls

1. Meningitis is a life-threatening medical emergency; maintain a high index of suspicion for all signs and symptoms.

2. Absence of meningeal signs in infants <18 months old does NOT exclude meningitis. In this age group, such signs are often not present, and when seen, usually represent a very late finding.

3. Stiff neck is a pathognomonic sign of meningeal irritation from a purulent exudate or hemorrhage in the subarachnoid space.

4. CSF examination is the gold standard for diagnosis; always perform LP when there is any suspicion of meningitis. Neutrophils may predominate early even in viral meningitis. Decreased CSF glucose may also occur in mumps and herpes meningoencephalitis.

5. Petechiae or purpura are seen in only 70% of cases of meningococcemia. Patients with meningococcal meningitis may also lack CSF abnormalities on initial LP even with a positive CSF culture. Consider infections caused by N meningitides even in the absence of skin lesions or CSF abnormalities.

6. Seizures are seen in about 20% to 30% of patients with bacterial meningitis; consider meningitis in children presenting with seizures associated with fever.

7. Avoid delays in initiating antibiotic therapy while awaiting completion of diagnostic studies.

8. Failure to diagnose meningitis early is a leading cause of malpractice litigation in pediatrics.

The authors acknowledge the special contributions of Radha Giridharan, MD and Joseph A. Sykes, MD to prior edition.

Clinical Summary

Sustained elevations in intracranial pressure (ICP) may permanently retard normal brain function, especially in the developing brain. By volume, skull contents consist of brain (80%), blood (10%), and CSF (10%), and this volume is fixed. Increases in one component therefore must be compensated by a decrease in the others (Monroe-Kellie hypothesis); otherwise there will be an increase in ICP leading to brain compression. Normal values for ICP vary according to age and body position (normal <20 mm Hg). Patients with elevated ICP may be asymptomatic or present with nausea, headache, blurry vision, weakness, vomiting, or seizures. Clinical signs may be present, including tachycardia or bradycardia, bradypnea, hypertension, focal neurologic deficits, bulging fontanel (infants) or widening diathesis of cerebral sutures, doll’s eye, papilledema, retinal hemorrhages, and unequal pupils.

Emergency Department Treatment and Disposition

Sustained ICP elevations (>20 mm Hg) need to be treated aggressively, and management is dependent on etiology. The factors contributing to ICP, including cerebral blood flow (CBF), cerebral perfusion pressure (CPP), mean arterial pressure (MAP), guide treatment. As CBF increases, ICP increases. CBF is autoregulated under a wide range of CPP and remains relatively constant. CPP is the difference between MAP and ICP. When ICP is not immediately available, central venous pressure (CVP) can be used instead of ICP to calculate CPP. In adolescents/adults, CPP ranges between 70 and 90 mm Hg when MAP is between 60 and 150 mm Hg. In children, the CPP is 50 to 70 mm Hg. From these relationships, to maintain constant CBF and ICP, constant CPP must be maintained.

Adhere to PALS and ATLS guidelines and mitigate any factors that may further compromise CPP. If ICP elevation is from trauma, immobilize the cervical spine and intubate trachea under rapid sequence protocol especially if Glasgow Coma Scale score is <8. Initiate mechanical ventilation and maintain normal ventilation (Paco2 between 35 and 40 mm Hg), optimize oxygenation by maintaining Pao2 > 110, and maintain normal acid-base status. Hyperventilation (Paco2 <35 mm Hg) and hypoventilation are to be avoided. Hypoventilation and hypoxemia cause vasodilation and lead to an increase in CBF, leading to increased ICP. Hyperventilation leads to vasoconstriction of the cerebral vasculature leading to ischemia from decreased blood flow. When maximizing oxygenation, minimize PEEP to avoid decreases in venous drainage, which increase ICP and reduces cerebral perfusion. Avoid hyperoxia (ie, Pao2 >110 mm Hg). Intubation raises ICP and negatively affects CPP. To minimize this, sedate the patient with fentanyl and etomidate and use lidocaine prior to intubation. Use short-acting drugs whenever possible to allow for accurate and frequent assessment of neurologic status. When a patient with increased ICP requires tracheal intubation, placement of an ICP monitor is recommended.

Maximization of CPP is dependent on augmenting MAP and minimizing ICP and requires that central venous volume be optimized. If CVP is decreased, resuscitate the patient. Crystalloid is superior for initial resuscitation. If the CVP is adequate and the MAP remains low to maintain adequate CPP, then initiate inotropes and vasotropes. Femoral vein cannulation is preferable for central access as placement of catheter in the superior circulation may retard cerebral venous drainage and decrease CPP. Consult neurosurgery immediately. Order noncontrast head CT to aid in diagnosis and management. Address factors that worsen ICP (see Table 3.3).

If herniation is suspected (unequal pupil size, irregular respiration, hypertension, altered respirations and bradycardia, abnormal CT), prompt attention is warranted. In this case, implement the above recommendations and administer mannitol unless renal failure, severe dehydration, cerebral hemorrhage, or pulmonary edema are present. If an intraventricular catheter is in place, diversion of CSF externally may decrease ICP. Hyperosmolar therapy with 3% normal saline can be initiated in the emergency department (ED); however, goals may not be achieved until much later.

Pearls

1. The Cushing triad (bradycardia, bradypnea, and hypertension) need not be present concomitantly in pediatric patients with increased ICP.

2. Goal of increased ICP management is to maintain adequate CPP.

3. Administer short-acting pharmaceuticals for sedation, analgesia, and paralysis whenever possible. Continuous propofol infusion is rarely indicated in children.

Clinical Summary

Alteration in the level of consciousness (LOC) is a common presentation in the ED and is a vague term that requires evaluation to be specified. Consciousness requires both cerebral hemispheres and the brainstem ascending reticular activating system to be functional. The spectrum of altered consciousness includes lethargy, confusion, delirium, obtundation, stupor, and coma, and causes of altered LOC include a wide spectrum of disorders.

Emergency Department Treatment and Disposition

Obtain a history and vital signs with attention to possible causes. Fever suggests infectious etiology (eg, encephalitis, meningitis). Hypothermia may indicate metabolic or toxic conditions. Tachypnea is seen in hypoxia, sepsis, acidosis, and toxins. Central nervous system (CNS) involvement with increased ICP and herniation will cause Cheyne-Stokes respiration. General examination may show signs of trauma and infection. A brief focused neurologic examination can reveal significant information. Use the Glasgow Coma Scale to measure LOC; using the parameter of motor response to pain helps to also determine any focal weakness. Obtain finger stick blood glucose, metabolic panel (electrolytes, blood urea nitrogen [BUN], creatinine, Ca, liver enzymes, Mg, PO4, etc), CBC, arterial blood gas analysis, and urinalysis. Monitor cardiorespiratory status and stabilize patient with evaluation and maintenance of ABCs (airway, breathing, and circulation). If trauma is suspected, immobilize cervical spine until cervical trauma is ruled out. Administer IV dextrose 25%, if finger stick glucose is not available to confirm hypoglycemia. Administer thiamine 100 mg IV to adolescents if alcohol intoxication or thiamine-deficient states are suspected. If clinically indicated, administer naloxone, for opioid intoxication. Order urgent head CT if symptoms and signs of raised ICP are present or if no metabolic cause is identified. Perform a lumbar puncture if infectious etiology is considered. Initiate specific therapy for various causes based on the assessment (eg, antibiotics for meningitis, anticonvulsants for seizures, correction of electrolyte and acid-base imbalance, antidote for toxic overdose). Obtain specific consultations depending on the etiology of the coma (eg, neurosurgery for intracranial bleed, poison control for toxic ingestion, neurology for stroke). After initial stabilization, admit to ICU for continuous monitoring and further management.

Pearls

1. Altered mental status has a very wide differential diagnosis; it is essential to treat the underlying cause.

2. Pupillary assessment helps differentiate metabolic and structural causes of coma; reactive pupils suggest metabolic causes, while asymmetric or absent pupillary responses suggest trauma.

3. Features of increased ICP and herniation include headache, vomiting, altered mental status, Cushing triad (systolic hypertension, bradycardia, bradypnea) and unequal pupils.

Clinical Summary

Febrile seizures are an age-related phenomenon in which a child between 6 months to 5 years of age has fever and a generalized seizure not associated with CNS infection or any other definable cause (eg, metabolic abnormality) or previous history of afebrile seizures. Types of febrile seizures are listed in Table 13.7.

Emergency Department Evaluation and Disposition

Strongly consider performing lumbar puncture in infants <12 months of age. Between ages 12 and 18 months, LP should be considered. After the age of 18 months, LP is not routinely warranted, but should be done if meningeal signs are present. Obtain laboratory studies (CBC, chemistry, etc) based on clinical evaluation. Treat ongoing seizure activity with benzodiazepine IV or rectally. The rectal preparation comes in a pre-dosed syringe (2.5, 5, 10, 15, and 20 mg), making it easy to deliver. Absorption is rapid and effective in interrupting seizure clusters or repetitive seizures. Give antipyretics to make the child more comfortable.

Neither continuous nor intermittent anticonvulsant therapy is recommended for children with 1 or more simple febrile seizures. When the risk of recurrence is high, intermittent oral diazepam at onset of febrile illness may be effective in preventing recurrence. Risk factors for recurrence include early age at first onset, epilepsy or febrile seizures in a first-degree relative, day nursery (increased frequency of febrile episodes), or a first complex febrile seizure. In the absence of risk factors and age >15 months, recurrence is 10% in 18 months. In the presence of 1 to 2 risk factors, recurrence is 25% to 50%; with 3 or more factors, risk is 50% to 100%. Neuroimaging and electroencephalogram (EEG) are not recommended routinely after the first febrile seizure.

Pearls

1. Febrile seizures are common in young children (2%–5%) and generally benign with an overall excellent prognosis in most cases.

2. Aim treatment at determining cause of fever and terminating seizure activity.

3. Strongly consider lumbar puncture in children <18 months of age, as meningitis may present with fever and seizures without meningeal signs in this age group.

Clinical Summary

Seizures result from abnormal and excessive synchronized neuronal firing, and are characterized by intermittent stereotypical, usually unprovoked, disturbances in consciousness, behavior, emotion, motor function, or sensation. Convulsion is a lay term used to describe excessive, abnormal muscle contractions, usually bilateral, which may be sustained or uninterrupted. Epilepsy is the occurrence of recurrent unprovoked seizures. Aura is the portion of the seizure experienced before consciousness is lost and for which memory is retained. When aura occurs alone, it constitutes a simple partial seizure. Automatism is a more or less coordinated, repetitive, motor activity that usually occurs during altered consciousness that is not usually remembered by the patient and may resemble a voluntary movement or inappropriate continuation of ongoing preictal motor activity. Generalized tonic-clonic seizures and partial seizures constitute 75% of all the seizure types in childhood followed by absence epilepsy (15%) and other generalized epilepsies including catastrophic syndromes (10%).

Symptomatic seizures follow a triggering event such as fever, head trauma, electrolyte imbalance, hypo- or hyperglycemia, meningitis, encephalitis, etc. Seizures must be differentiated from other paroxysmal disorders that occur commonly in children. Some examples include episodes without alteration in consciousness like tics, rhythmic motor habits or mannerisms, shuddering spells, rigors (with any febrile illness), jitteriness (newborn period), hypnagogic jerks (sleep myoclonus), benign myoclonus of infancy, benign paroxysmal vertigo, gastroesophageal reflux, cardiac dysrhythmias, Munchausen syndrome by proxy, and nonepileptic (pseudo) seizures. Episodes associated with change in consciousness may also be mistaken for complex partial seizures (eg, delirium with any febrile illness, syncope, cyanotic breath-holding attacks, pallid syncopal attacks, night terrors, migraine [the aura or confusional and basilar artery variants] or narcolepsy).

Emergency Department Evaluation and Disposition

Obtain a detailed history and neurologic examination, determine if a seizure has occurred or not and possible cause of the seizure. Order tests based on history or clinical findings (eg, vomiting, diarrhea, dehydration, or failure to return to baseline alertness) and toxicology screening (if possibility of drug exposure or substance abuse). Consider lumbar puncture if there is concern for meningitis or encephalitis. An EEG is recommended as part of the neurodiagnostic evaluation of the child with an apparent first unprovoked seizure; however, it is not required in the ED and may be performed nonemergently unless the child is in status epilepticus.

Children with new-onset unprovoked seizures do not require hospitalization and should be referred to their primary care physician for follow-up. The majority will have few or no recurrences (risk of recurrence is ˜40%, which rises to 80% after a second unprovoked seizure). About 75% of all recurrences occur within 6 months, and very few occur after 2 years. Treatment with anticonvulsants may be considered in circumstances where the benefits of reducing the risk of a second seizure outweigh the risks of pharmacologic and psychosocial side effects. Consult neurology to assist in such decisions.

Pearls

1. MRI is the preferred neuroimaging modality for unprovoked new-onset seizures.

2. Obtain emergent head CT in any child exhibiting a postictal focal deficit (Todd paresis) not quickly resolving, or who has not returned to baseline within several hours after the seizure.

3. Long-term anticonvulsant therapy is not routinely started in a child with the first unprovoked seizure.

Clinical Summary

Status epilepticus is defined as a seizure of >30 minutes’ duration or 2 or more sequential seizures without full recovery of consciousness between seizures. A more practical definition is a seizure of 5 to 10 minutes’ duration, because the vast majority of self-limiting generalized seizures stop 2 to 3 minutes after onset, and almost all cease within 5 minutes. Acute repetitive seizures are those that recur at frequent intervals, with full recovery between seizures. Seizure clusters may occur regularly at certain times in some patients (eg, around menstruation). Status epilepticus may be convulsive (partial or generalized tonic clonic) or nonconvulsive (including absence and complex partial).

Status epilepticus may be the initial manifestation in one-third of epilepsy cases. One-third of status cases occur in previously diagnosed epilepsy. One-third occur as a result of an acute isolated brain insult. Status epilepticus is more common in infants and young toddlers, and >50% of cases occur below the age of 3 years.

In patients with epilepsy, common causes of status include low anticonvulsant levels, sudden withdrawal of antiepileptic medications, failure to adhere to medication regimen, and drug interactions. Other causes include fever, toxic causes (alcohol, drugs, poisons), CNS infections (eg, herpes encephalitis), trauma, stroke, acute hydrocephalus, electrolyte imbalance (hypoglycemia, hyponatremia, hypocalcemia), and progressive degenerative disorders.

Emergency Department Evaluation and Disposition

The first step in management is the ABC of life support; monitor vital signs, pulse oximetry, and electrocardiography. Administer anticonvulsants to stop the seizure safely and quickly while minimizing treatment-related morbidity. Pay close attention to the systemic effects of status epilepticus and the side effects of treatment (sedation, cardiovascular, and respiratory compromise). Obtain a fingerstick glucose test as soon as possible to detect hypoglycemia and administer IV glucose if hypoglycemia is found or suspected. In adolescents, administer IV thiamine 100 mg first. Take blood for CBC, chemistries, toxicology screening, and anticonvulsant levels, if applicable. Watch for hyperthermia, which can occur in 28% to 79% of patients. If available, use continuous bedside EEG to monitor therapy. Admit patient to ICU for further management and monitoring.

Pearl

1. Identify the cause and precipitating factors and provide specific antidote if a cause is known (eg, pyridoxine for status epilepticus due to isoniazid overdose).

Clinical Summary

Stroke is the sudden occlusion or rupture of cerebral blood vessels resulting in focal cerebral damage causing clinical neurologic deficits. Strokes in children are relatively rare and diagnosis is frequently delayed. Stroke is either ischemic (either arterial embolic or thrombotic or venous sinus thrombosis) or hemorrhagic. Risk factors for stroke in children include cardiac abnormalities (eg, atrial septal defect, ventricular septal defect, cyanotic heart disease, myocarditis, endocarditis, arrhythmias), vascular abnormalities (eg, vasculitis, lupus, moyamoya, Ehler-Danlos syndrome, fibromuscular dysplasia, AV malformation, Sturge-Weber syndrome), hematologic disorders (eg, sickle cell disease, protein C or S deficiency, antithrombin III deficiency, thrombocytopenia), metabolic disorders (eg, homocystinuria, organic acidurias, mitochondrial disorders), trauma (eg, child abuse, arterial dissection, blunt cervical arterial trauma, intraoral trauma), or systemic disorders (eg, diabetes mellitus, hypertension). Typically, stroke is an acute neurologic event manifesting as hemiparesis with or without seizures, which are relatively frequent at stroke onset in children compared to adults. Seizures, fever, headache, lethargy occur more commonly in younger children. Dystonia is more common in children with basal ganglia infarction. Neonatal strokes manifest with persistent acute focal seizures.

Emergency Department Treatment and Disposition

Consult neurology emergently for a child with a sudden-onset focal neurologic deficit, as stroke in children may have many causes, is difficult to diagnose and may have therapeutic implications. Obtain an emergent head CT to look for fresh blood and subarachnoid hemorrhage. CT findings of ischemic stroke appear as low density fitting a vascular territory (findings similar to adults). Hemorrhagic infarcts have additional high density components. MRI is more sensitive than CT in detecting small and multiple infarcts. Diffusion weighted and perfusion weighted imaging have improved early detection and specificity of ischemic injury. Perform MR angiography (MRA) at the same time as MRI as it adds valuable information regarding the cerebral arteries and angiomatous malformations. MRA is noninvasive and correlates well with conventional angiography, with ischemic stroke MR venography the diagnostic study of choice in sinovenous thrombosis. CT angiography (helical CTA) can provide diagnostic information; however, exposure to excessive radiation in children is of concern. When dissection is suspected, conventional angiography is the criterion standard.

Thrombolytic agents (tissue plasminogen activator [tPA]) have been effective in adults when administered within 3 hours of onset of stroke symptoms. Use of thrombolytic agents in children with arterial ischemic stroke has been rare; however, accumulating experience with antithrombotic and anticoagulant treatment in children suggest that these agents can be safely used. Hospitalize patient to ICU for monitoring and ongoing care.

Pearls

1. Recognize STROKE means BRAIN ATTACK.

2. Differentiate ischemic from hemorrhagic stroke. In children, ischemic and hemorrhagic stroke are similar in frequency, unlike adults.

3. Quickly assess if patient is a candidate for thrombolytic therapy (time is of essence: within 3 hours).

4. Consider antithrombotic, anticoagulant, or anticonvulsant administration.

Clinical Summary

Neurocysticercosis is a CNS infestation by the larval stage of Taenia solium (tapeworm), resulting from ingestion of T solium eggs. Symptoms depend on the number, stage, and localization of parasites in the nervous system, and the severity of the host’s immune response to the parasite. Seizures are the most common presentation occurring in about 70% of the patients. Increased ICP may result from hydrocephalus (meningeal infestation results in arachnoiditis and adhesions leading to obstruction or from ventricular cysts), pseudotumor, giant cysts, or cysticercal encephalitis. Focal neurologic deficits may result from direct compression by the cysts or transiently secondary to seizures (Todd phenomenon). Spinal cord may also be involved, more commonly with leptomeningeal larval infestation, while intramedullary involvement is uncommon. Consider diagnosis of neurocysticercosis in any patient with new onset of partial or secondarily generalized seizures, especially if the patient has either recently migrated or recently traveled to one of the endemic regions.

Emergency Department Treatment and Disposition

Use noncontrast head CT to detect calcifications, which are present in 50% of the cases. Cysts appear as small, round, low-density lesions, with an eccentric hyperdense mural nodule (scolex). Edema around the lesion indicates a dying cyst. Use of contrast causes ring enhancement. The most common finding of neurocysticercosis in a patient with seizures is a single small enhancing lesion. Multiple cysts (“starry night”) may be seen in some patients. Extensive edema is seen with an encephalopathic presentation. Brain MRI is useful for assessing the degree of infection, location and evolutionary stage of the disease, and helps to identify lesions in the brainstem, cerebellum, base of the brain, eye and spinal cord; however, it will not pick up small calcifications. Differential diagnoses of the imaging findings include tuberculoma, brain abscess, fungal abscess, toxoplasmosis, brain tumor, and infectious vasculitis. Immunologic testing may be performed using serum or CSF. Enzyme-linked immunoelectrotransfer blot (EITB) is a very sensitive and specific test; however >30% of patients with a single brain lesion may test negative.

Admit patients with signs of increased ICP, hydrocephalus, or encephalitic presentation. Consult neurology for treatment, which depends on the lesion type. Antiparasitic medications (cysticidal drugs) include albendazole and praziquantel. Albendazole has been shown to be superior to praziquantel and a 1-week course of therapy is adequate. Treatment of a single solitary calcified lesion is controversial. Use corticosteroids in combination with cysticidal drugs in cases with arachnoid involvement, encephalitic presentation, multiple live cysts, spinal cysts, and ventricular cysts. Consult neurosurgery for shunt placement if hydrocephalus is present.

Pearls

1. Neurocysticercosis is a parasitic infestation of the CNS and the most common cause of acquired epilepsy worldwide.

2. Cysticercosis is endemic in various regions in the world including Latin America, India, Africa, and China.

3. Seizures are the most common presentation.

4. Neuroimaging is the main diagnostic investigation.

Clinical Summary

Bell palsy is an idiopathic condition characterized by a lower motor neuron (peripheral) facial neuropathy and is most often unilateral (98%–99%). The facial nerve has a long intracranial and extracranial course beginning in the pons at the facial nerve nucleus and ending in the parotid gland. Etiology of facial neuropathy is varied, and evidence of other neurologic symptoms and signs are often seen. Isolated facial nerve involvement is seen in Ramsay-Hunt syndrome secondary to herpes zoster infection. The typical presentation of Bell palsy is sudden-onset unilateral facial paresis that evolves rapidly and maximizes within 2 days. Associated symptoms include hyperacusis, decreased production of tears, and altered taste. Ear pain or fullness and mild facial pain may be present. Severe pain should raise the suspicion of Ramsay-Hunt syndrome. Neurologic examination reveals isolated lower motor neuron facial weakness with inability to wrinkle the forehead, impaired closure of the eye, drooping of the brow and corner of the mouth, and difficulty closing the mouth. Bell phenomenon (upward eye movement on attempted eye closure) is seen because of incomplete closing of the eye.

Emergency Department Treatment and Disposition

Examine the ear canal, palate, and tongue. Vesicles suggest Ramsay-Hunt syndrome and opacity of the tympanic membrane, granulations and polyposis suggest middle ear pathology. Check for skin lesions such as erythema migrans, which suggest Lyme disease as a cause. If there are no other findings besides unilateral facial paresis, a diagnosis of Bell palsy can be made clinically, and no further workup may be required in the ED. Provide treatment to hasten recovery and prevent corneal complications. Use lubricating eye drops, applied several times daily to protect the cornea from drying and abrasion due to impaired eye closure. Use a lubricant eye ointment and the eye taped shut at night. Do not use gauze as it can dry the eye further by a wicking effect of the gauze. Give oral prednisone of 1 mg/kg/day for 5 to 7 days, then taper over next 5 days and discontinue. Steroids should ideally be given within the first 72 hours of symptom onset. The role of antiviral agents in Bell palsy is not clear. Acyclovir may be administered orally. Most patients start to improve with or without treatment in 2 weeks, and complete recovery may occur in 2 to 3 months.

Pearls

1. Differentiate Bell palsy, which causes a complete unilateral involvement of the face from upper motor neuron (central) facial paresis, which spares the forehead.

2. Bilateral facial palsy is seen in Lyme disease, Miller Fisher syndrome and Guillain-Barré syndrome, HIV, meningitis, and pontine lesions.

Clinical Summary

Headache in children and adolescents is common and may be a primary disorder, such as migraine or tension type headache, or secondary to a systemic illness or a CNS disorder. Migraine is seen in about 10% of children aged 5 to 15 years and has a genetic component with history of migraine reported in at least one parent in 90% of cases. Headaches can present as acute generalized, acute localized, recurrent acute, chronic nonprogressive, and chronic progressive forms. Raised ICP is of major concern when a child presents to the ED with headaches. Signs and symptoms suggestive of intracranial pathology include morning headache on wakening, aggravation by sneezing/coughing, recurrent localized headache, persistent vomiting, progressive frequency or severity, diplopia, papilledema, strabismus, focal neurologic deficit, and macrocephaly.

Signs suggestive of increased ICP include new-onset sixth nerve palsy (unilateral or bilateral) which is a false localizing sign. Third nerve palsy is more ominous (ptosis, abduction, and dilated pupil), suggesting uncal herniation. Downward deviation of both eyes (sunsetting) indicates impaired upgaze due to pressure on the tectum of the midbrain, seen in central herniation. Central upward herniation due to pressure from the posterior fossa can cause reverse sunsetting, with impaired downgaze.

Uncal herniation causes declining consciousness, dilated and fixed ipsilateral pupil, decerebrate rigidity, increased blood pressure, bradycardia, and respiratory irregularity. Central transtentorial herniation causes declining consciousness, decerebrate or decorticate rigidity, impaired upward gaze, irregular respiration, papillary constriction or dilation. Cerebellar herniation will lead to decreased level of consciousness, impaired upgaze, irregular respiration, lower cranial nerve palsies, neck stiffness, or head tilt. Headaches due to ominous conditions leading to increased ICP almost always have abnormal findings on examination.

Emergency Department Treatment and Disposition

Take a detailed history with attention to the duration (days, weeks, months, years); location (frontal, occipital, hemicranial, bitemporal); timing (on awakening, morning, afternoon, evening, from sleep); quality (throbbing, pulsatile, pressure, tight band etc); frequency (daily, weekly, monthly); and severity (mild, moderate, severe, scale 1–10) of the headaches. Note any visual symptoms (flashing lights, double vision, scotomas, obscurations) or nausea/vomiting, photophobia/phonophobia, and relieving factors (analgesics, sleep etc). Perform a careful neurologic examination including mental status assessment and fundus exam, and check cranial and motor nerves, cerebellar, and gait evaluation.

Obtain a head CT for the first or “worst” headache, progressive symptoms, macrocephaly, any abnormality on neurologic examination, presence of ventriculoperitoneal shunt, age <3 years, pain in the occipital region, nuchal rigidity, or suspicion of hemorrhage. Neuroimaging is usually not necessary in a patient with typical migraine or tension-type headache. Use brain MRI in a nonemergent situation, as it provides better information about the posterior fossa, craniocervical junction, sellar region, etc. Use contrast when infection, inflammation, or mass lesion is suspected. Perform a lumbar puncture if infection is suspected, or pseudotumor is a consideration, and measure opening pressure of CSF to confirm the diagnosis.

Management depends on the underlying cause. Nonsteroidal anti-inflammatory agents (ibuprofen or naproxen) can help abort most migraine headaches, if acetaminophen does not help. Triptans are approved for abortive treatment of uncomplicated migraine in children over the age of 12 years.

Pearls

1. Majority of children with headaches DO NOT have intracranial structural lesions.

2. Neuroimaging is not indicated in all patients presenting with headache to the ED.

3. Increased ICP will manifest abnormalities on neurologic examination.

4. The American Academy of Neurology practice parameter for evaluating recurrent headaches in children states that presence of a space-occupying lesion is suggested by headache lasting <1 month, absence of family history of migraine, abnormal neurologic findings on examination, gait abnormality, and occurrence of seizures.

Clinical Summary

Brain tumors are the most common solid tumors in childhood, and the second most frequent malignancy (next to leukemia) in children. Posterior fossa tumors account for nearly 85% of tumors in children >1 to 2 years old and include medulloblastoma, cerebellar astrocytoma, ependymoma, and brainstem glioma. Supratentorial tumors are less common and include astrocytoma, oligodendroglioma, pineal tumors, ganglioglioma, and sellar and suprasellar tumors. Clinical manifestations depend on tumor location and whether it is slow growing or rapidly expanding. In rare instances, with tumors in infancy, enlarging head circumference may be the presenting feature. More commonly, symptoms of increased ICP including headache, vomiting, impaired vision and alteration in consciousness are seen. Signs of increased ICP are sixth nerve palsy (false localizing sign) and papilledema. Depending on the location, other neurologic signs may develop, such as cranial nerve deficits, spasticity, hyperreflexia, ataxia, and dysmetria. Seizures may be seen in tumors involving the cerebral hemispheres, but are not common (<1% of new-onset seizures result from a brain tumor).

Cerebellar astrocytomas are slow-growing tumors, characterized by a large cystic lesion with a mural nodule. Symptoms include insidious and intermittent headaches, unsteady gait, and vomiting. Papilledema, ataxia (mild or severe), and dysmetria may be present. Cranial nerve palsies, head tilt, and neck stiffness may be present in advanced tumors. Medulloblastomas are rapidly growing tumors in the vermis or fourth ventricle extending into cerebellar hemispheres and presenting with vomiting (most common initial symptom), headache, unsteady gait, and torticollis. Examination reveals papilledema, with truncal ataxia and dysmetria. Ependymomas are slow-growing tumors in the fourth ventricle presenting with increased ICP, hydrocephalus, unsteady gait, neck pain or stiffness, nystagmus, and cranial nerve dysfunction. Medulloblastomas and ependymomas tend to seed the subarachnoid space, leading to metastases in the spinal cord and ventricular system. Brainstem gliomas are diffuse infiltrating tumors predominantly involving the pons and present with bilateral cranial nerve palsies, with corticospinal involvement such as hemiplegia and ataxia, dysphagia, and hoarseness. Signs of increased ICP are not seen early in the course. Vomiting can be present because of irritation of the emetic center in the brainstem.

Tumors involving the cerebral hemispheres are less common and depending on the site of involvement, the presenting features vary. Midline tumors involving the pineal gland, midbrain, and thalami tend to obstruct the CSF pathways leading to hydrocephalus and increased ICP. Tumors involving the pituitary and hypothalamus present with endocrine disturbances and visual field defects.

Differential diagnosis includes other space-occupying lesions (eg, brain abscess, tuberculomas), postinfectious conditions (eg, acute disseminated encephalomyelitis with symptoms of encephalopathy and raised ICP), and idiopathic intracranial hypertension (pseudotumor cerebri) presenting with increased ICP with normal neuroimaging.

Emergency Department Treatment and Disposition

Obtain a head CT scan that helps to screen for large space-occupying lesions and hydrocephalus. For more optimal diagnosis, brain MRI, with and without contrast, is essential. Management in the ED includes stabilization of the patient, with symptomatic treatment. Consult neurology and neurosurgery and admit to ICU or a monitored bed for further management.

Pearls

1. The presenting symptoms of brain tumors can be nonspecific; thus a high index of suspicion is necessary.

2. Consider brain tumors in the differential for any child presenting with increased ICP of unclear etiology.

Clinical Summary

Hydrocephalus is accumulation of excess CSF in the intracranial space, and is classified as communicating (when CSF communicates through the ventricular system and subarachnoid space) or noncommunicating (when there is a block within the system). Causes of communicating hydrocephalus include meningeal fibrosis or obstruction (due to inflammatory or infectious conditions), posthemorrhagic or neoplastic infiltration, and less commonly excessive production of CSF (choroid plexus tumor). Noncommunicating or obstructive hydrocephalus can result from aqueductal stenosis (congenital or secondary to compression from mass lesions), congenital malformations (eg, Arnold-Chiari or Dandy-Walker malformation) or vein of Galen aneurysm. Presenting symptoms depend on the age and cause of hydrocephalus, which can be acute or longstanding. Enlarging head circumference is the most common presenting feature in young infants. Acute signs of increased ICP in infants can be very nonspecific, such as irritability, poor feeding, vomiting, and lethargy, with bulging fontanel on examination. When hydrocephalus develops gradually, enlarging head size may be the only symptom. On examination, besides increased head circumference, frontal or parietal bossing, wide or bulging anterior fontanel, separation of sutures, prominent scalp veins, sunsetting sign, head lag, spasticity, and brisk deep tendon reflexes may be present.

In older children, symptoms are those of increased ICP, such as headache and vomiting, with lethargy, if the presentation is acute. On examination, papilledema may be seen, with increased tone and brisk reflexes. If the hydrocephalus is secondary to a mass lesion/tumor, focal neurologic signs are present depending on the site of the lesion. Sixth nerve palsy is a common finding (a false localizing sign). Paralysis of upgaze or Parinaud syndrome is a relatively specific sign of compression of the tectum of the midbrain. This is equivalent to the sunsetting sign seen in young infants.

Emergency Department Treatment and Disposition

Obtain a noncontrast head CT to confirm the presence of hydrocephalus, and in acute presentations, identify conditions such as posthemorrhagic hydrocephalus (eg, following traumatic or spontaneous subarachnoid hemorrhage), and determine if surgical treatment is needed. Order brain MRI with and without contrast to determine etiology. Low-grade midbrain tumors (eg, tectal glioma) can cause aqueductal stenosis and are not readily identified on CT. Brain MRI will also show other mass lesions, such as posterior fossa tumors (eg, medulloblastoma, ependymoma, astrocytoma), not seen well on CT, which does not delineate structures well in the posterior fossa.

Management includes drainage of the CSF and treatment of the cause (eg, tumor resection). Surgical diversionary procedures help drain CSF from the intracranial region. Most commonly, a ventriculoperitoneal (VP) shunt is placed. Programmable shunts can be adjusted to the required pressure for optimal drainage using a magnetic programming device to set the appropriate pressure level. After placement, shunt infection and obstruction are of concern. Shunt infection usually presents in the first 2 months after the insertion of the shunt. Besides fever, there may be redness and swelling around the shunt tubing. An infected shunt can become obstructed, leading to features of increased ICP. The neurosurgeon may perform a shunt tap under strict aseptic conditions to draw CSF from the proximal tubing to determine presence of infection.

Shunt obstruction can occur without infection at any time after insertion and may be proximal or distal. Proximal obstruction may be due to entangled choroid, or the shunt end may have migrated out of the ventricles into the parenchyma. Distal obstruction in the peritoneal cavity can be secondary to fibrosis, formation of a pseudocyst or peritonitis. Breakage of shunt tubing is an uncommon cause of shunt malfunction and a shunt series can be performed to evaluate the shunt integrity when obstruction or malfunction is suspected by obtaining radiographs of the skull, chest, and abdomen. Head CT should be done to evaluate ventricular size compared to prior scans to determine the degree of obstruction. Sometimes, the size of the ventricles may not show any change, but the child is symptomatic. This can be due to poor compliance of the ventricular lining (“stiff ventricle syndrome”). Overdrainage of the CSF can lead to collapse of the ventricles with symptoms of increased ICP (“slit ventricle syndrome”).

Pearls

1. Hydrocephalus can present at any age and it is important to determine the cause.

2. Head CT is useful for emergent evaluation and management, but MR is the imaging of choice to determine the etiology.

3. A CT scan is NOT necessary every time a child with a VP shunt presents to the ER, unless obstruction or malfunction is strongly suspected.

Clinical Summary

Patients with spinal cord conditions present with paraparesis/quadriparesis, sensory disturbances, back pain, bladder and bowel dysfunction, autonomic dysfunction, and change in reflexes. Cranial nerves are typically not involved. In toddlers, the most common complaint is refusal to stand or walk, suggesting an acute process that results from weakness and/or pain. Older children present with difficulty walking, sensory complaints, and bladder distension. Typical neurologic findings include relatively symmetric weakness of lower extremities (upper extremities weakness also with cervical spine involvement), hyperreflexia, and a sensory level. In an acute presentation, areflexia due to spinal shock may be present.

Acute nontraumatic spinal cord lesions include transverse myelitis, infections like diskitis, epidural abscess, tuberculous osteomyelitis (Potts disease), and myelitis due to herpes zoster. Spinal cord tumors such as astrocytoma, ependymoma, or neuroblastoma can present with subacute or chronic course of pain and weakness, with bladder and bowel involvement. Congenital malformations (eg, syringomyelia, arachnoid cyst, Chiari malformation, tethered cord, or spinal dysraphism) have a more chronic indolent course. Vascular conditions (eg, arteriovenous malformation, angiomas) may present acutely or with a gradual onset.

Acute spinal cord lesions are a neurologic emergency. A complete history and pertinent neurologic evaluation can point to a diagnosis. Of concern is diagnosis of cord compression mandating emergent management, which is of utmost importance for neurologic recovery. Extramedullary lesions (either intradural or extradural) lead to cord compression. Extradural lesions include tumors like neuroblastomas, ganglioneuromas or sarcomas; epidural abscess, hematoma, or metastases. Intradural lesions include neurofibromas, lipomas, angiomas, or meningiomas. Tumors within the spinal cord (intramedullary) include astrocytomas and ependymomas. Tumors tend to progress slowly over weeks to months. Vascular conditions such as spinal cord infarction (though uncommon) have the most rapid course, progressing in <4 hours.

Idiopathic acute transverse myelitis is a demyelinating condition (diagnosis of exclusion). Spinal cord involvement typically is short (1-2 segments). Longitudinally extensive transverse myelitis (LETM), more common in younger children, refers to involvement extending beyond 3 segments. LETM is characteristic of neuromyelitis optica (NMO) in adolescents and adults. Multiple sclerosis can also cause a demyelinating lesion, and is seen more often in children >12 years of age. Acute disseminated encephalomyelitis presents with lesions both in the CNS and spinal cord. Demyelinating disorders tend to progress quickly and symptoms may be present for less than a week, usually 2 to 4 days. Conditions presenting similar to transverse myelitis include systemic autoimmune disorders (eg, lupus, mixed connective tissue disease) and postinfectious diseases (eg, Lyme disease, Epstein-Barr virus [EBV], mycoplasma, herpes simplex virus, cytomegalovirus). Guillan-Barré syndrome can be in the differential, but the presence of a sensory level rules this condition out.

Emergency Department Treatment and Disposition

Order spinal MRI with and without contrast to identify spinal pathology that is intra- or extramedullary. Extramedullary (intradural/extradural) lesions may require immediate neurosurgical intervention. Transverse myelitis typically reveals swelling of the cord, with high T2 signal intensity lesion within the spinal cord, with patchy enhancement following contrast. If the spinal cord reveals transverse myelitis, order MRI of the brain to exclude lesions in the brain and optic nerves. Perform a lumbar puncture if there are no structural lesions. Transverse myelitis is associated with mildly elevated protein, mild lymphocytic predominance and presence of myelin basic protein. If postinfectious etiology is suspected, order appropriate tests (eg, Lyme titers, EBV, mycoplasma, herpes simplex virus polymerase chain reaction).

Admit patient to ICU or a monitored bed because symptoms may continue to progress. Cord compression due to structural lesions requires urgent neurosurgical intervention. Catheterize patient with bladder distension. Transverse myelitis is treated with high-dose IV methylprednisolone and for severe cases, intravenous immune globulin (IVIG) and plasmapheresis are other options.

Pearls

1. Absent reflexes can be a sign of spinal shock.

2. Cord compression due to structural lesions requires urgent neurosurgical evaluation.

Clinical Summary

Guillain-Barré syndrome (GBS) is an immune-mediated disease directed against the peripheral nervous system myelin, with or without involvement of the axon. The main presenting feature is weakness, initially distal and symmetric that can rapidly progress within 24 hours to ascending weakness and bulbar involvement, requiring ventilatory assistance. Facial involvement is bilateral in 50% of cases and lower motor neuron facial weakness can be seen. Ptosis and extraocular weakness, unsteady gait, and areflexia are characteristics of a variant of GBS, called Miller-Fisher syndrome. The course consists of progressive weakness, which reaches a maximum in the first 2 weeks of the illness in more than 50% of the individuals. Recovery begins gradually 2 to 4 weeks after progression. Vague insidious sensory symptoms are often present at onset, with fleeting paresthesias and muscle tenderness. Younger children complain of pain. Recent history of viral illness may often be present. Neurologic examination reveals diffuse weakness (distal more than proximal), with prominent areflexia. Autonomic dysfunction is common, with tachycardia, blood pressure instability (hypo- or hypertension), abdominal pain, and bowel or bladder incontinence.

Emergency Department Treatment and Disposition

Ascending weakness and vague sensory complaints should raise the suspicion of GBS. Admit all patients with clinically suspected GBS to the ICU in case rapid progression of weakness and autonomic instability requires appropriate supportive care and treatment with IVIG. Measure and monitor vital capacity to check for bulbar involvement, which may require intubation and ventilation. Perform lumbar puncture if the illness has been present for >1 week. Elevated protein in CSF with normal (<10) cell count (albuminocytologic dissociation) is diagnostic after the first week of illness (earlier CSF tests may be normal). Order CBC, comprehensive metabolic panel and tests for postinfectious etiology (eg, EBV, mycoplasma, campylobacter jejuni, Lyme titers). Spine MRI with contrast may reveal enhancement of the nerve roots. Nerve conduction studies (performed after hospitalization) aid in confirmation of GBS.

Pearls

1. GBS is also known as acute inflammatory demyelinating polyneuropathy.

2. Rapid symmetric ascending weakness with areflexia is the hallmark of GBS.

3. Autonomic instability can be prominent.

Clinical Summary

Myasthenia gravis (MG) is a group of disorders of neuromuscular transmission, differing in age of onset and clinical features. Most commonly it is autoimmune in etiology and characterized by fluctuating asymmetric weakness and fatigue, involving extraocular, oropharyngeal, neck and/or skeletal muscles, with normal sensation and reflexes.

Ptosis or ophthalmoplegia (90% of patients) is the most prominent clinical feature, and ptosis is often asymmetric and variable. Extraocular muscle weakness is the only manifestation in 10% to 15% of patients. Over 50% of children presenting with ocular symptoms progress to systemic or bulbar weakness in 2 years. Bulbar weakness, seen in 75% of patients, presents with drooling, slow chewing and swallowing, nasal voice or poor cough. Facial weakness can be present. Diffuse muscle weakness (prominently proximal) presents as fatigability, inability to run, climb stairs and keep up with peers. Weakness of diaphragm and respiratory muscles may cause respiratory failure. Spontaneous remission of symptoms (often transient) can occur and symptoms can recur after a period of time. MG can be graded clinically by the Osserman scale as follows:

• Grade I – weakness restricted to extraocular muscles
• Grade II – generalized weakness (mild IIa, moderate IIb)
• Grade III – severe generalized weakness
• Grade IV – life-threatening weakness of respiratory musculature (‘myasthenic crisis’).

Diagnosis is essentially clinical and confirmatory tests include immunologic studies (acetylcholine receptor antibodies and muscle-specific kinase antibodies; a large proportion of pediatric patients may be seronegative), electrophysiological studies (EMG/nerve conduction) and pharmacological testing (eg, edrophonium).

Emergency Department Treatment and Disposition

Suspect MG if a child presents to the ED with generalized weakness or more acutely with respiratory distress. Take a careful clinical history for prior symptoms especially when neurologic examination reveals abnormalities only in the motor system, with normal mental status, normal pupillary response, normal deep tendon reflexes, sensation, coordination and a normal general examination. Assess vital signs including respiratory status and obtain vital capacity in cooperative patients, if possible. Provide respiratory support, either noninvasive (CPAP/BiPAP) or invasive (intubation) as needed in the ED.

Consult neurology for bedside edrophonium testing. Edrophonium is a short acting (5 minutes) inhibitor of acetylcholinesterase and improves neuromuscular transmission. After an initial test dose, give edrophonium via IV and monitor symptoms for improvement. Keep atropine available to counteract any adverse events such as bradycardia, abdominal cramps and worsening of oropharyngeal weakness. Alternatively, neostigmine can be given SQ or IM with effect lasting up to 4 hours. Side effects are similar to edrophonium.

Intubate patients with significant weakness and respiratory compromise. Admit to the ICU for ventilator management and further care, including IVIG or plasma exchange for very weak patients. Treat mildly affected patients with oral pyridostigmine (Mestinon). Long term therapy includes use of immunosuppressants (eg, prednisolone, azathioprine, cyclosporine). Thymectomy may help some of the patients.

Pearls

1. MG is characterized by weakness and easy fatigability with diurnal variation; symptoms are less on awakening and become more obvious as the day progresses.

2. Ptosis and extraocular muscle involvement may be the only manifestations.

3. Pupillary reaction is always normal.

4. Bulbar and respiratory muscle involvement can cause myasthenic crisis.

5. Edrophonium testing is a useful bedside diagnostic tool.