NEUROLOGY Flashcards
Epilepsy – disorder of the brain characterized by an enduring predisposition to generate seizures and by the neurobiological, cognitive, psychological, and social consequences of this condition; ______ unprovoked seizures occurring in a time frame of ____
two or more
>24 hrs
disorder that manifests one or more specific seizure types and has a specific age of onset and prognosis
Epileptic syndrome
- Formerly known as partial seizure
- initial activation of a system of neurons limited to part of 1 cerebral hemisphere
- Subdivided into:
- Focal Seizures without impairment of consciousness (previously known as simple partial seizures)
- Focal Seizures with impairment of consciousness a.k.a. focal dyscognitive seizures (previously complex partial seizures)
Focal Seizures
Clinical and EEG changes indicate synchronous involvement of all or both hemispheres
Generalized Seizures
Most common type OF BENIGN EPILEPSY SYNDROMES WITH FOCAL SEIZURES
benign childhood epilepsy with centrotemporal spike
Benign Epilepsy with occipital spikes
-
Panayiotopoulos type
- Early childhood
- Complex partial seizures with ictal vomiting
-
Gastaut Type
- Later childhood
- Complex partial seizure, visual auras, migraine headache
Triad of West Syndrome
o Infantile epileptic spasms
o Developmental regression
o EEG = hypsarrhythmia (very chaotic and disorganized brain electrical activity with no recognizable pattern)
Lennox-Gastaut Syndrome Triad
- Developmental delay
- Multiple seizure type: absence, myoclonic, astatic and tonic
- EEG = 1-2hz spike and slow waves, polyspike bursts in sleep and slow background in wakefulness
starts during the 1 st 2 months of life with severe myoclonic seizures and burst suppression pattern on EEG o usually caused by inborn errors of metabolism
Early myoclonic infantile encephalopathy
similar age of onset and EEG but manifests tonic seizures and is usually caused by brain malformations or syntaxin binding protein 1 mutations.
Early infantile epileptic encephalopathy (Ohtahara syndrome)
starts as focal febrile status epilepticus or focal febrile seizures and later manifests myoclonic and other seizure types
Severe myoclonic epilepsy of infancy (Dravet syndrome)
formerly called ‘petit mal’, involve brief staring spells that usually last for less than 15 seconds; usually resolves 2-5 years after its onset, usually at puberty
Absence seizures
1st line of treatment in absence seizures
Ethosuximide
Alternative: Lamotrigine and Valproate
Lumbar puncture should be performed in all patients below _______ old for a first febrile seizure.
18 months
Local guidelines by Child Neurology Society of the Philippines on a first febrile seizure:
- Lumbar puncture should be performed in all patients below 18 months old for a first febrile seizure.
- For those equal or above 18 months old, LP should be done in the presence of clinical signs of meningitis.
- Neuroimaging studies should not be routinely done in children for a first simple febrile seizure.
- The use of continuous anticonvulsants is not recommended in children after a first febrile seizure.
- The use of intermittent anticonvulsants (whether Diazepam or Phenobarbital) is not recommended for the prevention of recurrent febrile seizures.
- EEG should not be routinely requested for in children with a first simple febrile seizure.
WHEN TO DO LUMBAR TAP?
- all infants younger than 6 mo of age who present with fever and seizure or if the child is ill-appearing or at any age if there are clinical signs or symptoms of concern
- Is an option in a child 6-12 mo of age who is deficient in Haemophilus influenzae type b and Streptococcus pneumoniae immunizations or for whom immunization status is unknown
Most common seizure disorder during childhood
SIMPLE FEBRILE SEIZURE
- usually associated with a core temperature that increases rapidly to ≥39°C.
- It is initially generalized and tonic-clonic in nature, lasts a few seconds and rarely up to 15 min, is followed by a brief postictal period of drowsiness, and occurs only once in 24 hr.
COMPLEX OR COMPLICATED FEBRILE SEIZURE`
- when the duration is >15 min
- when repeated convulsions occur within 24 hr
- when focal seizure activity or focal findings are present during the postictal period.
It is defined as continuous seizure activity or recurrent seizure activity without regaining of consciousness lasting for more than 5 min as part of an operational definition put forth within the past few years.
STATUS EPILEPTICUS
strongest evidence for initial and emergent therapy FOR STATUS EPILEPTICUS is
diazepam or lorazepam, followed by Phenytoin/Fosphenytoin and phenobarbital, then valproate and levetiracetam
In patients developing febrile status epilepticus, what viral infection is most commonly associated in one third of the cases?
HHV-6 and HHV7 (ROSEOLA)
Major and minor risk factors for recurrence of Febrile seizures
risk factor with the highest risk of occurence of subsequent epilepsy after a febrile seizure.
Neurodevelopmental abnormalities
Syntaxin binding protein
Ohtahara Syndrome
• MECP2, CDKL5 and protocadherin 19
Rett Syndrome
ARX gene; polymerase G
West Syndrome
SCN1A
Dravet Syndrome
Triad of Imaging Findings in TB Meningitis?
- Hydrocephalus
- Basal Enhancements
- Infarcts
Where is CSF produced?
o Choroid plexus epithelium within the cerebral ventricles
CSF Flow
Choroid Plexus
Lateral Ventricle
Foramen of Monro (Interventricular foramen)
Third Ventricle
Aqueduct of Sylvius (Cerebral aqueduct)
Fourth Ventricle
Foramina of Luschka
Foramen of Magendie
Superior Sagittal Sinus
Arachnoid Villi
How is CSF reabsorbed?
Arachnoid villus cells, which are located in the superior sagittal sinus, return CSF to the bloodstream within vacuoles (via a process called pinocytosis)
Absolute contraindications to a lumbar puncture are the following:
- Signs of elevated intracranial pressure (decreased or fluctuating level of consciousness, relative bradycardia and hypertension, focal neurological signs, abnormal posturing, unequal, dilated or poorly responsive pupils, papilledema, and abnormal Doll’s eye movement);
- Local infection at desired puncture site; and
- Radiological signs (in cranial scan or MRI) of obstructive hydrocephalus, cerebral edema or herniation and the presence of an intracranial mass lesion or midline shift
Relative contraindications to LP (lumbar puncture may be done but only after appropriate diagnostic and therapeutic interventions are done):
- Signs of shock, sepsis or hypotension
- Coagulation defects [disseminated intravascular coagulopathy (DIC), platelet count <50,000/mm 3 , and therapeutic use of warfarin]
- Focal neurological deficit (especially for suspected posterior fossa lesions)
- Glasgow coma score < 8
- Epileptic seizures
Patients presenting with CNS infections
Indications for surgery in brain abscess
- (+) gas in the abscess
- Multiloculated abscesses
- Posterior fossa location
- Fungal cause
- Assoc. infections like mastoiditis, periorbital abscess, sinusitis
absence of meningitis indicate a better prognosis of Meningococcemia. TRUE or FALSE.
FALSE
The presence of petechiae for <12 hr before admission, absence of meningitis, and low or normal erythrocyte sedimentation rate indicate rapid, fulminant progression and poorer prognosis.
- Asymptomatic colonization to fulminant sepsis
- Infections of the GUT, conjunctiva, pharynx, CNS, heart, skin, adrenals
- Diffuse adrenal hemorrhage without vasculitis, DIC, coma, and death - Waterhouse-Friderichsen syndrome (fulminant cases)
MENINGOCOCCEMIA
DRUG OF CHOICE for MENINGOCOCCEMIA
- Penicillin G 250,000-300,000 U/kg/day IV in 4-6 divided doses for at least 5-7 days (DOC)
- Ceftriaxone IM or IV (100 mg/kg/day once or twice a day) or Cefotaxime IM or IV (200-300 mg/kg/day every 6 or 8 hours) o * clinical improvement within 24-72 hrs
PATIENT PRESENTING WITH CNS INFECTIONS
What do you give to personnel exposed to Meningococcemia?
- Children: Rifampicin 10 mg/kg po every 12 hrs for a total of 4 doses (max 600 mg); 5 mg/kg/dose for <1 month old
- Or Ceftriaxone 125 mg single dose IM for < 12 yrs old
- > 18 yrs old: Ciprofloxacin 500 mg po as a single dose
The recommended dose of folate to prevent NTDs during the first pregnancy:
400 micrograms or 0.4 mg of folic acid
* succeeding pregnancies or recurrent cases of NTDs: 4000 micrograms or 4 mg of folic acid
the most severe form of neural tube defect (dysraphism)
MENINGOCELE
What parts are affected in MYELOMENINGOCELE?
o Dysfunction of the skeleton, skin, GUT, PNS, CNS
o May be located anywhere along the neuroaxis (lumbosacral 75%)
o flaccid paralysis of the LE
o absence of DTRs
o lack of response to pain & touch
o hip subluxation
o clubfeet
o bowel & bladder incontinence
o associated with hydrocephalus (type II Chiari)
MYELOMENINGOCELE
- failure of closure of the anterior neuropore
- 50% assoc with polyhydramnios
Anencephaly
Absence of cerebral convolutions; smooth brain on CT/MRI
Lissencephaly (Agyria)
What are the features of migraine?
Recurrent headache with symptom-free intervals & at least 3 of the ff: (F-R-U-A-N-T)
- (+) Family history
- Relief following sleep
- Unilateral location
- Associated aura
- Abdominal pain
- Nausea & vomiting
- Throbbing in character
How do you explain the aura in migraine?
Cortical spreading depression (CSD) – a phenomenon associated with high CNS hydrogen & potassium ions with the release of glutamate & nitrous oxide → leads to excitation of trigeminalvascular system → activates the release of VIP → vasodilation → extravasation of plasma proteins from the dural vessels → localized inflammation of dural vessels → excitation of pain sensitive receptor → pain
Arise from a defect in differentiation of the primitive ectoderm
NEUROCUTANEOUS SYNDROMES
- Tuberous sclerosis
- Neurofibromatosis
Genes mutated in TUBEROUS SCLEROSIS
Tuberous sclerosis complex gene 1 (TSC1) and gene 2 (TSC2)
*TSC1 encodes for the protein hamartin and TSC2 encodes for the protein tuberin.
These skin lesions are associated with what disease?
Tuberous Sclerosis
- Typical hypopigmented skin lesions: ash leaf
- shagreen patch – roughened, raised lesion with an orange-peel consistency located primarily in the lumbosacral region
- Adolescence: subungual or periungual fibromas from the fingers & toes
Von Recklinghausen disease
NEUROFIBROMATOSIS
- AD disorder; every system may be affected; complications may be delayed for decades
- Result of an abnormality of neural crest differentiation & migration during the early stages of embryogenesis
Von Recklinghausen disease is located on wat chromosome number
chromosome 17
NEUROFIBROMATOSIS 1
NF-1: most prevalent type: diagnosed when any 2/7 of the ff are present:
- 6 or more café au lait macules >5mm in diameter in prepubertals & >15mm in postpubertal individuals: present at birth & increase in size, number & pigmentation with predilection for the trunk & extremities with sparing of the face
- Axillary or inguinal freckling consists of multiple hyperpigmented areas 2-3 mm in diameter
- 2 or more iris Lisch nodules (hamartomas located within the iris)
- 2 or more neurofibromas (along the skin, PNS, blood vessels & within viscera) or one plexiform neurofibroma
- Distinctive osseous lesion
- Optic glioma
- 1 st -degree relative with NF-1 whose diagnosis was based on the aforementioned criteria
NEUROFIBROMATOSIS 2
NF-2 is diagnosed when 1 of the ff is present:
- Bilateral 8 th nerve masses (acoustic neuroma)
- Parent, sibling, or child with NF-2 & either unilateral 8 th nerve masses or any 2 of the ff: neurofibroma, meningioma, glioma, schwannoma
SUMMARY OF NEUROCUTANEOUS SYNDROMES
Increased protein, normal glucose, normal cells
Cytoalbuminocytologic dissociation found in GBS
- Postinfectious polyneuropathy involving mainly motor
- Not hereditary; affects all ages
- Paralysis usually follows a nonspecific viral infection (GIT or RT) by 10 days (Campylobacter jejuni and herpesvirus)
- Weakness begins in the lower extremities & progressively involves the trunk, upper limbs & bulbar muscles (Landry ascending paralysis)
Guillain-Barre syndrome (GBS) or acute demyelinating polyradiculo-neuropathy (symmetric ascending muscle weakness or paralysis)
Miller-Fisher syndrome is associated with what disease?
GBS
* acute ophthalmoplegia, ataxia, areflexia
last function to recover & lower extremity weakness last to resolve in GBS
Tendon reflexes
MANAGEMENT OF GBS
- Acute stage: admit for observation because ascending paralysis may occur within 24 hrs
- Rapidly progressive ascending paralysis: IVIG (0.4 gms/kg/day for 5 consecutive days)
- Supportive care; prevention of ulcers
- High-dose pulse methylprednisolone IV for relapses
most common malignant brain tumor in children
medulloblastoma
* It accounts for about 20% of primary CNS neoplasms and approximately 40% of all posterior fossa tumors.
Homer-Wright rosettes are seen in what brain tumor?
MEDULLOBLASTOMA
INFRATENTORIAL TUMORS
- Cerebellar astrocytoma – most common & with the best prognosis; cystic; causes hydrocephalus; resection with 90% 5yr survival rate
- Medulloblastoma – < 7 year old; can spread to extracranial sites; surgery + irradiation; 80-90% 5-yr survival rate
- Brain stem glioma
• Ependymoma
SUPRATENTORIAL TUMORS
- Craniopharyngioma – solid & cystic areas that tend to calcify; short stature; pressure to optic chiasm produces bitemporal visual field defects
- Optic nerve glioma – decreased visual acuity & pallor of the discs; 25% have neurofibromatosis; hyperalert & euphoric despite being emaciated; invasion of the hypothalamus leads to obesity or DI
• Astrocytoma
• Choroid plexus papilloma
The most common cause of arterial ischemic stroke in pediatric population is:
Arteriopathy - disorders of cerebral arteries
This type of intracranial hemorrhage is almost always associated with trauma:
Epidural
MCC of childhood subarachnoid and intraparenchymal hemorrhagic stroke
AV malformation
REsults from defective cleavage of the procencephalon ; associated with midline facial abnormalities - cyclopia
Holoprosencephaly
