Neurology Flashcards
account for the largest proportion of congenital anomalies of the CNS
Neural tube defect
- result from failure of neural tube to close spontaneously between the 3rd and 4th wk of in utero development
What is an atypical dimple that warrants imaging?
deep, > 5 mm , >25 mm from anal verge
Which part of the brain is CSF formed?
ventricular system by the choroid plexus
Hydrocephalus resulting from obliteration of the subarachnoid cisterns or malfunction of the arachnoid villi
non-obstructive/communicating hydrocephalus
— most commonly follows a subarachoid hemorrhage
hydrocephalus resulting from obstruction within the ventricular system
obstructive or noncommunicating
— most commonly associated with an abnormality of the aqueduct of Sylvius or lesion in the 4th ventricle
most prominent sign in infants with hydrocephalus
accelerated rate of enlargement of the head
most important imaging modality in identifying the specific cause and severity of hydrocephalus
CT scan and/or MRI + Cranial UTZ
Most common megalencephalic syndrome
Sotos Syndrome (Cerebral gigantism)
Type of NTD: cerebral hemispheres are absent or represented by membranous sacs with remnants of frontal, temporal or occipital cortex dispersed over the membrane
Hydranencephaly
major complications of shunting
occlusion
bacterial infection
represents the most severe form of dysraphism
Myelomeningocele
Folic acid supplementation is proven to reduce the incidence of NTDs in pregnancy at risk by at least 50%, thereby, it should be taken when?
before conception and continued until at least 12th wk of gestation
what dose of folic acid should be taken during pregnancy
0.4 mg OD
but if high risk pregnancy, 4 mg OD
most frequent type of recurrent headache
Migraine
definition of chronic migraine
if it occurs more than 15 days per month
most common form of migraine in both children and adults
Migraine without aura
Define status migrainosus
migraine that persists beyond 72 hours
Major risk factor for bacterial meningitis
lack of preexisting immunity to specific pathogens and serotypes
Most important step/procedure in the diagnosis of Meningitis
Lumbar puncture
contraindications of lumbar puncture
- evidence of increased ICP
- severe cardiopulmonary compromise (eg shock)
- infection of the skin overlying the site of LP
initial emperic treatment for children suspected with meningitis
3rd generation cephalosporin (usually Ceftriaxone) + Vancomycin
enumerate the most common neurologic sequelae from meningitis
hearing loss (sensorineural hearing loss - most common)
cognitive impairment
recurrent seizures
delay in acquisition of language
visual impairment
behavioral problems
Chemoprophylaxis given for close contacts with meningococcal meningitis
Rifampicin (10 mkdose) q12 for 2 days or
Ceftriaxone 125 mg IM x 1 for <15 yr old
Ceftriaxone 250 mg IM x 1 for >15 yr old
or
Ciprofloxacin 500 mg PO x 1
Prophylaxis given to all household contacts of patients with invasive disease caused by H. influenza type B
Rifampin (20 mkday) OD for 4 days
Predominant organisms that cause brain abscesses
Streptococci sp.
risk of developing epilepsy who have first afebrile seizure
30%
if normal neuro PE and other tests, 20%
this test should be performed in all cases of a first unprovoked nonfebrile seizure to help predict the risk of seizure recurrence
routine EEG
febrile seizures usually occur during this age group
6 and 60 months
— peak 12-18 months
difference between simple febrile seizure and complex febrile seizure
SFS: generalized, lasting for 15 min (max), not recurrent within a 24 hr period
CFS: prolonged (>15 min), focal, recurs within 24 hours
duration of Febrile status epilepticus
30 minutes
percentage of neurologically healthy infants who experience at least 1 simple febrile seizure
between 2% and 5%
major risk factors for recurrence of febrile seizures
Age < 1 yr
Duration of fever <24 hr
Fever 38-39 C
recurrence risk of children with febrile sezure who have no risk factors
12%
mutation in this gene is the most common cause of Dravet Syndrome
SCN1A gene
this micronutrient deficiency is associated with an increased risk of febrile seizures
Iron deficiency
most common hereditary neuromuscular disease affecting all races and ethnic groups
Duchenne muscular dystrophy
clinical features of Duchenne Muscular Dystrophy
Progressive weakness
Intellectual impairment
Hypertrophy of the calves, with proliferation of connective tissue and progressive fibrosis in muscle
what test is greatly elevated in DMD
Serum CK level
— usually at 15K to 35K
(normal <160)
what is the type of muscle affected in autoimmune myasthenia gravis?
striated muscles
— particularly extraocular, palpebral muscles and swallowing
characteristic feature of MG that distinguishes it from most other neuromuscular diseases
Rapid fatigue of muscles
Primary therapeutic agent for MG
Cholinesterase-inhibiting drugs such as Pyridostigmine bromide (0.5-1 mg/kg/dose every 4-6, max dose 7 mkday)
Medications that can potentiate myasthenia
Aminoglycosides
Beta blocking agents
Procainamide
Chloroquine
Fluoroquinolones
autoimmune disorder thought to be a postinfectious polyneuropathy, involving mainly motor nerves
Guillan-Barré Syndrome
initial symptoms of Guillan-Barre Syndrome
weakness usually begins in the LE, progressively involves the trunk, upper limbs and finally bulbar muscles
diagnostic of GBS based on CSF studies
High CSF protein and a lack of cellular response (cytoalbuminologic dissociation)
Treatment for severe or rapidly progressive muscle weakness in GBS
IVIG (0.4 g/kg/day) for 5 consecutive doses or (1g/kg/day) for 2 days
last function in GBS to recover
Tendon reflexes
function to recover first in GBS
bulbar function
most common long-term residuum of GBS
Fatigue
features needed for diagnosis of GBS
-progressive weakness in legs and arms
- areflexia in weak limbs
acute-onset peripheral facial nerve palsy not associated with any other cranial nerve neuropathies or brainstem dysfunction
Bell palsy
most common causes of Bell palsy
Active/reactivation of herpes simplex or Varicella-zoster virus
primitive reflex which remains throughout life
Parachute reflex
Drugs that antagonize Folic acid hence these should not be given ideally to pregnant women
Trimethoprim
Anticonvulsants such as Carbamazepine, Phenytoin, Phenobarbital and Primidone
uncommon GBS variant associated with acute external ophthalmoplegia, ataxia and areflexia
Miller-Fisher Syndrome (MFS)
Most often involved nerve in MFS
6th cranial nerve
How to diagnose migraine without aura
A. At least 5 attacks fulfilling criteria B to D
B. HA attacks lasting 4-72 hr (untreated or unsuccessfully treated)
C. HA has at least 2 of the ff 4 characteristics:
1. Unilateral location
2. Pulsating quality
3. Moderate to severe pain intensity
4. Aggravation by or causing avoidance of routine physical activity (walking/climbing stairs)
D. During headache at least 1 of the ff:
> Nausea and/or vomiting
> Photophobia and phonophobia
E. Not better accounted for by another ICHD-3 diagnosis
Triggers for migraine
Skipping meals
Inadequate or irregular sleep
Dehydration
Weather changes
Potential cause of headache with papilledema in children with normal standard findings in brain MRI
Idiopathic intracranial hypertension// Pseudotumor cerebri
percentage of children who experience at least 1 seizure (febrile/afebrile) in the first 16 years of life
4-10%
4 obligatory criteria in distinguishing Muscular dystrophies from all other neuromuscular disease
- It is a primary myopathy
- It has a genetic basis
- Course is progressive
- Degeneration and death of muscle fibers occur at some stage in the disease
GBS may follow administration of vaccine against?
Rabies
Influenza
Conjugated Meningococcal
features needed for diagnosis of GBS
Progressive weakness in legs and arms
Areflexia in weak limbs
most common long-term residuum of GBS
Fatigue
