USMLE Neuro and ID Flashcards
Treatment of myoclonic seizures
Valproic acid
The radial nerve passes through which anatomical region, which may be affected by repetitive pronation/supination of the forearm?
Supinator canal
Methylmalonic acidemia
AR organic acidemia due to complete/partial deficiency of methylmalonyl CoA mutase
Increased propionic acid, decreased serum glucose, increased urine ketones, increased ammonia
Parinaud syndrome affects which part of the brain?
Dorsal midbrain
Germinomas are the most common pineal gland tumor that is associated with this
Characteristics of Parinaud syndrome
Limitation of upward gaze, BL eyelid retraction (Collier sign) and light-near dissociation
What type of hemorrhage is a common complication of prematurity?
Intraventricular hemorrhage that originates from the germinal matrix
Occurs within the first 5 postnatal days
Can present with hypotonia
Vitamin A excess
Acute toxicity = nausea, vomiting, vertigo and blurred vision
Chronic = alopecia, dry skin, hepatic toxicity and enlargement; pseudotumor cerebri, hyperlipidemia and papilledema
Teratogenic (cleft palate, cardiac abnormalities)
Difference between Chiari I and Chiari II
Chiari I = ectopia of cerebellar tonsils; affects adults; headaches and cerebellar symptoms; associated with syringomyelia
Chiari II = herniation of vermis and tonsils through foramen magnum with aqueductal stenosis (leading to non-communicating hydrocephalus); associated with lumbosacral meningomyelocele
Agenesis of cerebellar vermis and cystic enlargement of 4th ventricle
Dandy-Walker
Which cranial nerve is most likely to be compressed with bleeding in temporal lobe and compression of anterior medial temporal lobe against free margin of the tentorium? TRANSTENTORIAL HERNIATION
CN III
Intranuclear eosinophilic inclusions and intracytoplasmic basophilic inclusions
Cytomegalovirus
First line tx = ganciclovir (guanine nucleoside anlogue that interferes with viral replication by competitively inhibiting incorporation of guanosine triphosphate into CMV DNA strands by CMV DNA polymerase)
AEs of ganciclovir
BM suppression, renal toxicity
Type of HS for rheumatic fever?
Type II immune mediated
Symptoms of rheumatic fever
Mitral regurg (early), mitral stenosis (late)
Joint (migratory polyarthritis) O (carditis) N (subQ nodules) Erythema marginatum Sydenham chorea
Tx of rheumatic fever
Penicillin
How do immunizations protect against hepatitis viruses?
Immunization uses recombinant HBsAg to generate anti-HBs antibodies, which prevent infection by binding to the envelope of circulating virus and inhibiting viral entry
gp120 and gp41 in HIV
gp120 = attachment to host CD4+ T cell
gp41 = fusion and entry
Protease inhibitors in HIV
-navir
Prevent maturation of new viruses
AE: hyperglycemia, nausea, diarrhea, lipodystrophy
Which NRTI is CI if pt has HLA-B*5701 mutation due to increased risk of hypersensitivity?
Abacavir
HIV therapy - NRTI
Competitive inhibit NT binding to reverse transcriptase and terminate the DNA chain
Tenofovir is a NT; all others are nucleosides
All need to be phosphorylated to be active
Which HIV NRTI can be used for general prophylaxis and during pregnancy?
Zidovudine
HIV attaches to host cells using what viral surface glycoprotein?
gp120
gp120 binds to CD4 molecule as the primary receptor and chemokine receptor CCR5 or CXCR4 as a coreceptor
Which transmembrane glycoprotein mediates viral fusion in HIV?
gp41
CCR5 and CXCR4 are coreceptors of HIV that bind to what type of cells?
Macrophages (early infection)
T cells (late infection)
