ABPN Child Neurology cheat sheet

Average term birth weight is 3.5 kg; weight doubles by 5 months, triples by 12 months; birth head circumference is about 35 cm.

Head circumference grows about 2 cm/month in the first 3 months, 1 cm/month from 4 to 6 months, and 0.5 cm/month from 6 to 12 months.

Motor milestones: head control at 4 months, sitting without support at 6–8 months, walking at 12–15 months.

Language milestones: cooing at 2 months, babbling at 6 months, first word at 12 months, two-word phrases at 18–24 months, three-word sentences at 3 years.

Primitive reflexes: Moro and grasp disappear by 4 months, asymmetric tonic neck reflex by 6 months; persistence suggests central or peripheral abnormality.

Fine motor milestones: pincer grasp at 9–12 months, tower of 2 cubes at 15 months, tower of 6 cubes at 2 years.

Red flags: no social smile at 2 months, no head control at 4 months, no sitting at 9 months, no walking at 18 months, no words at 16 months.

Loss of previously acquired milestones indicates developmental regression and requires metabolic, genetic, and neuroimaging evaluation.

Growth velocity is about 5 cm/year from ages 4 to 10 years; BMI rebound normally occurs at ages 5 to 7 years.

Lissencephaly: smooth cerebral surface; DCX mutations cause anterior-predominant pachygyria, while LIS1 deletions cause posterior-predominant lissencephaly with seizures and severe delay.

Joubert syndrome: cerebellar vermis hypoplasia with molar tooth sign on MRI, hypotonia, apnea, eye-movement abnormalities, and nephronophthisis in some ciliopathies.

Chiari II malformation: myelomeningocele, small posterior fossa, cerebellar tonsillar herniation, tectal beaking, and hydrocephalus; treatment is myelomeningocele closure and shunt as needed.

Dandy-Walker malformation: enlarged posterior fossa, vermian hypoplasia, cystic dilation of the fourth ventricle, and hydrocephalus.

Tuberous sclerosis complex: TSC1 or TSC2 mutations; cortical tubers, subependymal giant cell astrocytomas, cardiac rhabdomyomas, hypomelanotic macules, and infantile spasms.

NF1: six or more café-au-lait macules, axillary freckling, Lisch nodules, optic pathway glioma, plexiform neurofibromas, and risk of malignant peripheral nerve sheath tumor.

Sturge-Weber syndrome: GNAQ mutation, facial port-wine stain in V1, leptomeningeal angioma, glaucoma, seizures, and stroke-like episodes.

Fragile X syndrome: FMR1 CGG repeat expansion over 200 causes intellectual disability, macroorchidism, long face, and autism; premutation carriers may develop FXTAS.

Neonatal seizures are often subtle; EEG confirmation is required, and common causes are hypoxic-ischemic encephalopathy, hypoglycemia, hypocalcemia, infection, and intracranial hemorrhage.

Phenobarbital is first-line for neonatal seizures; levetiracetam or fosphenytoin may be used second-line.

Therapeutic hypothermia for moderate-to-severe HIE: 33.5°C for 72 hours, started within 6 hours of birth, in infants at 36 weeks or more gestation.

Sarnat stages of HIE: stage I mild with hyperalertness, stage II moderate with lethargy and seizures, stage III severe with coma and absent reflexes.

Intraventricular hemorrhage grades: I germinal matrix only, II intraventricular without dilation, III with ventricular dilation, IV with parenchymal involvement.

Neonatal stroke usually presents with seizures in the first days; most are arterial ischemic infarcts in the middle cerebral artery territory.

Kernicterus from severe hyperbilirubinemia damages the globus pallidus and auditory pathways, causing dystonia, hearing loss, and upward gaze palsy.

Apgar score: appearance, pulse, grimace, activity, respiration; each 0–2, total 0–10 at 1 and 5 minutes.

Focal seizures: start with carbamazepine, oxcarbazepine, or levetiracetam; generalized absence: ethosuximide; generalized tonic-clonic: valproate, avoiding valproate in females of childbearing potential.

Status epilepticus: benzodiazepine first, then fosphenytoin, levetiracetam, or valproate, then anesthetic agents for refractory cases.

Infantile spasms: hypsarrhythmia, clusters of flexor or extensor spasms, developmental regression; ACTH or vigabatrin, with vigabatrin first-line in tuberous sclerosis.

Absence epilepsy: 3-Hz generalized spike-and-wave, hyperventilation provocation, normal background, and remission in most; ethosuximide is first-line.

Lennox-Gastaut syndrome: multiple seizure types, tonic drop attacks, slow spike-and-wave, intellectual disability, and drug resistance; valproate, lamotrigine, or rufinamide are used.

Dravet syndrome: SCN1A mutation, prolonged febrile seizures in infancy, later multiple seizure types; sodium-channel blockers may worsen seizures.

Benign rolandic epilepsy: centrotemporal spikes, nocturnal focal motor seizures, normal development, and remission by adolescence.

Juvenile myoclonic epilepsy: morning myoclonic jerks, 4–6 Hz polyspike-wave, tonic-clonic seizures, and lifelong treatment usually with valproate or levetiracetam.

SUDEP risk is increased by uncontrolled generalized tonic-clonic seizures, nocturnal seizures, and poor medication adherence.

Duchenne muscular dystrophy: X-linked dystrophin deficiency, Gowers sign, calf pseudohypertrophy, elevated CK, dilated cardiomyopathy, and restrictive lung disease; corticosteroids slow progression.

Spinal muscular atrophy: SMN1 deletion, anterior horn cell degeneration, hypotonia, tongue fasciculations, and preserved cognition; treat with nusinersen, risdiplam, or onasemnogene abeparvovec.

Myasthenia gravis: fatigable ptosis and diplopia, anti-acetylcholine receptor antibodies, pyridostigmine, and immunotherapy; check for thymoma in adults.

Guillain-Barré syndrome: ascending symmetric weakness, areflexia, albuminocytologic dissociation, and respiratory monitoring; treat with IVIG or plasma exchange.

Charcot-Marie-Tooth disease: peroneal muscle atrophy, pes cavus, hammertoes, and sensory loss; CMT1A is caused by PMP22 duplication.

Botulism: descending flaccid weakness, ptosis, constipation, and pupillary dilation; antitoxin and supportive ventilation are used.

Myotonic dystrophy type 1: CTG repeat in DMPK, percussion myotonia, cataracts, cardiac conduction defects, and congenital form with hypotonia.

Bell palsy: lower motor neuron facial weakness, treated with corticosteroids and eye protection; MRI is not routine if examination is typical.

Sickle cell disease is a leading cause of pediatric stroke; acute stroke management includes exchange transfusion and hydration.

Moyamoya: progressive stenosis of distal internal carotid arteries with lenticulostriate collaterals giving a puff-of-smoke appearance; revascularization surgery reduces stroke risk.

Arterial ischemic stroke: MRI with diffusion-weighted imaging is most sensitive acutely; aspirin is used after hemorrhage is excluded.

Cerebral sinovenous thrombosis: headache, seizures, papilledema, and focal deficits; MR venography confirms and anticoagulation is generally started even with hemorrhagic infarction.

Cavernous malformation: popcorn-like lesion with hemosiderin rim on MRI; risk of hemorrhage and seizures, treated by resection if symptomatic.

Sturge-Weber syndrome: port-wine stain in V1, leptomeningeal angioma, seizures, glaucoma, and stroke-like episodes.

Pediatric stroke workup includes vascular imaging, echocardiography, thrombophilia testing, and lipid studies.

Hemorrhagic stroke in children is often due to arteriovenous malformation, aneurysm, or coagulopathy.

Medulloblastoma: midline cerebellar vermis tumor, headache, vomiting, ataxia, and drop metastases; treatment is surgery, craniospinal radiation, and chemotherapy.

Pilocytic astrocytoma: cerebellar cyst with mural nodule, BRAF-KIAA fusion, excellent prognosis, and complete resection may be curative.

Ependymoma: fourth ventricular floor tumor presenting with hydrocephalus; treatment is surgery and radiation, with cerebrospinal fluid dissemination risk.

Diffuse midline glioma: H3K27M mutation, pontine location, cranial nerve palsies, ataxia, and poor prognosis; radiation is palliative.

Craniopharyngioma: suprasellar calcified tumor causing visual field loss, growth failure, diabetes insipidus, and obesity; treatment is surgery and radiation.

NF1-associated optic pathway glioma: visual loss, proptosis, and chiasmatic involvement; chemotherapy is used for progressive lesions.

Posterior fossa tumor presentation: morning headache, vomiting, ataxia, papilledema, and head tilt from hydrocephalus or tonsillar herniation.

Tumor lysis syndrome: hyperkalemia, hyperphosphatemia, hyperuricemia, and hypocalcemia after chemotherapy; treat with hydration and rasburicase.

ADEM: post-infectious multifocal demyelination with encephalopathy; MRI shows poorly marginated white-matter lesions; treat with high-dose corticosteroids.

Multiple sclerosis: McDonald criteria use dissemination in space and time; oligoclonal bands in cerebrospinal fluid support diagnosis.

Neuromyelitis optica spectrum disorder: aquaporin-4 antibodies, longitudinally extensive transverse myelitis, optic neuritis, and area postrema syndrome.

MOG antibody disease: optic neuritis, ADEM-like presentation, and transverse myelitis; steroids are first-line and relapses may occur.

Anti-NMDA receptor encephalitis: psychiatric symptoms, seizures, dyskinesias, autonomic instability, and ovarian teratoma; treat with immunotherapy and tumor removal.

Bacterial meningitis: ceftriaxone plus vancomycin, with dexamethasone before or with first antibiotic dose in pneumococcal meningitis.

HSV encephalitis: temporal lobe involvement with fever, seizures, and confusion; start intravenous acyclovir before cerebrospinal fluid PCR results.

Lyme neuroborreliosis: facial palsy, meningitis, and radiculopathy; treat with doxycycline or ceftriaxone.

Phenylketonuria: phenylalanine hydroxylase deficiency, musty odor, eczema, intellectual disability, and seizures; treat with low-phenylalanine diet and sapropterin.

Galactosemia: galactose-1-phosphate uridyltransferase deficiency, jaundice, hepatomegaly, cataracts, and Escherichia coli sepsis; treat with lactose-free diet.

Maple syrup urine disease: branched-chain ketoacid dehydrogenase deficiency, sweet urine odor, encephalopathy, and increased leucine; treat with leucine-free formula and dialysis.

Urea cycle disorders: hyperammonemia, respiratory alkalosis, and encephalopathy; treat with sodium benzoate, arginine, and protein restriction.

Tay-Sachs disease: hexosaminidase A deficiency, cherry-red macula, regression, and seizures; no cure, with carrier screening available.

Krabbe disease: galactocerebrosidase deficiency, infantile irritability, hypertonia, and globoid cells; hematopoietic stem cell transplantation may slow early infantile disease.

Metachromatic leukodystrophy: arylsulfatase A deficiency, gait disturbance, regression, and demyelination; stem cell transplantation is used in early stages.

X-linked adrenoleukodystrophy: ABCD1 mutation, adrenal insufficiency, and progressive white-matter demyelination; Lorenzo oil may reduce onset in presymptomatic boys.

ADHD: at least six inattentive or hyperactive-impulsive symptoms for 6 months, present before age 12, in two or more settings, with impairment.

Autism spectrum disorder: social communication deficits and restricted repetitive behaviors; MCHAT screening at 18 and 24 months.

Tourette syndrome: multiple motor tics and at least one vocal tic for more than 1 year, onset before age 18; comorbid OCD and ADHD are common.

Intellectual disability: IQ below 70 with deficits in adaptive functioning and onset before age 18.

Dyslexia: reading difficulty despite normal intelligence and instruction; language-based learning disability with phonological processing deficits.

Disruptive mood dysregulation disorder: severe recurrent temper outbursts and persistent irritable mood for at least 12 months, starting before age 10.

Cerebral palsy: nonprogressive motor impairment from early brain injury; associated with epilepsy, intellectual disability, and visual or hearing deficits.

Stimulant treatment for ADHD: methylphenidate or amphetamine; monitor growth, blood pressure, and sleep.

Migraine without aura: at least five attacks lasting 4–72 hours with two of unilateral, pulsating, moderate-severe, or activity worsening, plus nausea or photophobia.

Tension-type headache: bilateral, pressing, mild-moderate, not worsened by activity, and without nausea.

Cluster headache: severe unilateral orbital pain with lacrimation, rhinorrhea, or ptosis, lasting 15–180 minutes; treat with oxygen and triptans.

Red flags for headache: thunderclap onset, fever, papilledema, morning vomiting, positional worsening, or focal neurologic deficit.

Concussion: graded return to learn before return to sport; avoid alcohol and driving until symptoms resolve.

Post-traumatic seizure prophylaxis: levetiracetam or phenytoin for 7 days after severe traumatic brain injury, but not for late seizure prevention.

Narcolepsy: cataplexy, sleep paralysis, hypnagogic hallucinations, and excessive daytime sleepiness; MSLT shows short sleep latency and REM sleep onset.

Obstructive sleep apnea in children: snoring, witnessed apneas, and daytime behavior problems; adenotonsillectomy is first-line for most.

Shunt malfunction: headache, vomiting, lethargy, and papilledema; obtain urgent neuroimaging and shunt series.