Infectious disease

Question 1

Acute HIV meningitis

Answer 1

seroconversion syndrome. alertness/cognition preserved. Normal LP

Question 2

Lyme disease Dx/Rx

Answer 2

CNS sxs? IV rocephin or Penicillin B x 2-4 weeks.
-B/l facial nerve palsy.  
-Cardiac conduction block in stage II
-Encephalitis, dementia stage III
No CNS sxs? doxycycline

Question 3

Mucormycosis

Answer 3

angioinvasive. zygomycosis. non-septated. cavernous/venous sinus thrombosis. Risk factors include immunosuppression, DM, DKA

Question 4

HIV associated dementia

Answer 4

etiology of this condition is the retrovirus itself rather than an opportunistic infection. Progressive cognitive decline and prominent psychomotor dysfunction are the main clinical manifestations. CSF analysis is nonspecific. Late stage of HIV. Rx HAART therapy/adherence

Question 5

West Nile encephalitis

Answer 5

asymptomatic sxs include fever. 20% can progress to encephalitis or WNV can also invade the anterior horn cells leading to flaccid weakness with arreflexia, similar to poliomyelitis

Question 6

Cryptococcus meningitis

Answer 6

CD4 counts fall below 100 cells/μL. LP w/increased opening pressure, mononuclear lymphocytosis with increased protein, low glucose levels. India ink smear is not very sensitive; Cryptococcal antigen detection in the CSF is rapid, sensitive and specific.
Rx amphotericin plus flucytosine for 2 to 3 weeks followed by PO fluconazole

Question 7

Toxoplasma gondii

Answer 7

intracellular protozoan, encysted bradyzoite.CD4 < 100/μL. Dx brain bx, typically treated empirically. sulfadiazine plus pyrimethamine w/folate supplementation. Alternative agent is clindamyin. Trimethoprim-sulfamethoxazole is used for prophylaxis less than 100/μL with positive IgG antibodies to toxoplasma

Question 8

primary CNS lymphoma

Answer 8

subacute focal neurologic manifestations, Associated with Epstein–Barr virus, positive CSF PCR to help make dx. Flow cytometry showing monoclonal B lymphocytes. MRI showing periventricular and deep regions of the brain with contrast enhancement, surrounding edema, and produce a mass effect.
Rx Corticosteroids, however s/p brain bx

Question 9

Progressive multifocal leukoencephalopathy (PML)

Answer 9

Polyomavirus. demyelinating. presents with a gradually progressive course of multiple focal neurologic manifestations, with visual field deficits and hemiparesis, sensory deficits.
Dx MRI findings and CSF JC virus DNA PCR

Question 10

HIV neuropathy

Answer 10

distal sensory neuropathy more frequently as the CD4 count drops 2/2 direct effects of the virus and cytokine upregulation. sensory, axonal length-dependent symmetric polyneuropathy.

Question 11

Nucleoside analog-associated neuropathy

Answer 11

occurs over weeks following the initiation of therapy

Question 12

PML MRI findings?

Answer 12

multiple white matter nonenhancing lesions that tend to coalesce and predominate in the parieto-occipital regions

Question 13

HIV myositis

Answer 13

induces major histocompatibility complex I expression with autoimmune muscle fiber injury

Question 14

lepromatous variant

Answer 14

occurs in patients with impaired cell-mediated immunity, making it possible for the organism to spread to the skin and peripheral nerves. sensory loss predominantly in the coolest regions of the body

Question 15

tuberculoid variant

Answer 15

occurs in patients with good cellular immunity, in which the disease is less disseminated. ulnar nerve is commonly affected, and the syndrome may resemble mononeuritis multiplex.

Dx inflammatory granulomas with epithelioid and mononuclear infiltrates and acid-fast organisms.
Rx rifampin, dapsone, and clofazimine

Question 16

Brain abscesses evolution

Answer 16

initial cerebritis in the first few days, then the formation of central necrosis with surrounding vasogenic edema, and the subsequent formation of a capsule
Rx third-generation cephalosporin (for streptococci and gram-negative bacilli), metronidazole (for anaerobes), and vancomycin (for staphylococci). The IV antibiotic regimen is continued for 6 to 8 weeks,

Question 17

cavernous sinus thrombosis

Answer 17

proptosis, compromise of the cranial nerves (CNs) traveling within the sinus (CNs V1 and V2, III, IV, and VI), retinal vein engorgement with retinal hemorrhages, and papilledema. Superior sagittal or the transverse sinuse thrombosis.

Question 18

tuberculous (TB) meningitis

Answer 18

granulomatous inflammatory response with multinucleated giant cells and caseating necrosis
Dx CSF demonstrates elevated protein level, low glucose level, and lymphocytic pleocytosis. AFB/cultures are poor tests, use PCR

Question 19

Whipple disease

Answer 19

Tropheryma whippelii. Presents with dementia, supranuclear ophthalmoplegia, ataxia, oculomasticatory myorhythmia and neuropathy, myopathy.
Dx duodenal bx showing PAF + macrophages
Rx IV ceftriaxone for 2 weeks, followed by a prolonged course of trimethoprim-sulfamethoxazole

Question 20

Treatment of neurosyphilis

Answer 20

CSF VDRL is very specific. penicillin G 4 million units every 4 hours for 14 days

Question 21

CJD

Answer 21

cellular prion protein (PrPC) to scrapie prion protein (PrPSc), which has an increased β-sheet content. PrPSc has the ability to bind to PrPC and induce its conformational change, therefore making this agent infective.
EEG repetitive sharp and wave periodic pattern.
MRI hockey-stick and pulvinar signs

Question 22

HSV diagnosis and treatment?

Answer 22

intravenous acyclovir 10 mg/kg every 8 hours x 2 weeks. FLAIR T2 hyperintensities and restricted diffusion in the temporal regions and PLEDs on EEG

Question 23

fatal familial insomnia

Answer 23

prion disorder characterized by progressive intractable insomnia and symptoms of sympathetic hyperactivity such as hypertension, tachycardia, hyperthermia, and hyperhidrosis. Patients may also have cognitive impairment, tremor, ataxia, hyperreflexia, and myoclonus.
Dx neuron loss/gliosis of the thalamus

Question 24

Gerstmann–Straussler–Scheinker

Answer 24

inherited prion disease that progresses slowly over years. Presents with cerebellar ataxia and dysarthria, sometimes extrapyramidal features followed by dementia

Question 25

Subacute sclerosing panencephalitis (SSPE)

Answer 25

late complication of measles: Acute encephalitis. Postviral encephalomyelitis. Measles inclusion body encephalitis and SSPE.
first 2 years of life are the ones at the greatest risk for SSPE

Question 26

SSPE symptoms

Answer 26

behavioral and personality changes, later causing seizures, myoclonus, spasticity, ataxia, choreoathetoid movements, optic atrophy, quadriparesis, autonomic instability, akinetic mutism, and eventually coma.

Question 27

Arbovirus

Answer 27

transmitted RNA viruses exist, including Saint Louis encephalitis virus, West Nile virus, La Crosse encephalitis virus, Japanese encephalitis virus, and Eastern and Western Equine encephalitis viruses.

Question 28

Aspergillus fumigatus

Answer 28

neutropenic patients, immunocompromised patients. invading blood vessels, causing stroke-like syndromes, infarcts, and hemorrhagic transformation. A vasculitis-type phenomenon. Forms granulomas in brain. septate hyphae that branch at acute angle

Question 29

Cryptococcus vs aspergillus vs histoplasmosis?

Answer 29

Cryptococcus causes meningitis and not typically a vasculitis-type syndrome. Histoplasmosis causes basilar meningitis, focal cerebritis, or granulomas

Question 30

Amebic meningoencephalitis

Answer 30

free-living amebae, such as Naegleria fowleri, Acanthamoeba, and Balamuthia mandrillaris

Question 31

Ramsay–Hunt syndrome

Answer 31

facial palsy combined with herpetic rash in the external auditory meatus, sometimes with vertigo, tinnitus, and deafness. This syndrome is secondary to geniculate ganglion involvement.

Question 32

VZV vasculopathy

Answer 32

Small and large intracranial vessels are involved, leading to ischemic strokes, TIAs, and sometimes aneurysmal dilatations with resulting subarachnoid or intracranial hemorrhages.
Dx Angio- showing multifocal segmental narrowing with poststenotic dilatation and anti-VZV IgG in the CSF has been demonstrated to be superior to the detection of VZV DNA

Question 33

VZV vasculopathy treatment?

Answer 33

should be treated with acyclovir 10 to 15 mg/kg IV three times a day for at least 2 weeks. Steroids may be required

Question 34

mycotic aneurysms

Answer 34

usually very distal in the arterial tree, and commonly seen in distal bifurcations. secondary to septic emboli involving distal vessels, affecting their vasa vasorum, with destruction and weakening of the arterial wall and subsequent aneurysmal dilatation. SAH is cortical and superficial, and is not generally associated with vasospasm.

Question 35

Rabies

Answer 35

cytoplasmic eosinophilic inclusions known as Negri bodies, which are found mainly in Purkinje cells and pyramidal cells of the hippocampus.
Rx s/p exposure HDCV (human diploid cell vaccine) and human rabies immunoglobulin (20 IU/kg) a