Infectious disease Flashcards
Acute HIV meningitis
seroconversion syndrome. alertness/cognition preserved. Normal LP
Lyme disease Dx/Rx
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
Mucormycosis
angioinvasive. zygomycosis. non-septated. cavernous/venous sinus thrombosis. Risk factors include immunosuppression, DM, DKA
HIV associated dementia
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
West Nile encephalitis
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
Cryptococcus meningitis
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
Toxoplasma gondii
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
primary CNS lymphoma
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
Progressive multifocal leukoencephalopathy (PML)
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
HIV neuropathy
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.
Nucleoside analog-associated neuropathy
occurs over weeks following the initiation of therapy
PML MRI findings?
multiple white matter nonenhancing lesions that tend to coalesce and predominate in the parieto-occipital regions
HIV myositis
induces major histocompatibility complex I expression with autoimmune muscle fiber injury
lepromatous variant
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
tuberculoid variant
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
Brain abscesses evolution
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,
cavernous sinus thrombosis
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.
tuberculous (TB) meningitis
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
Whipple disease
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
Treatment of neurosyphilis
CSF VDRL is very specific. penicillin G 4 million units every 4 hours for 14 days
CJD
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
HSV diagnosis and treatment?
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
fatal familial insomnia
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
Gerstmann–Straussler–Scheinker
inherited prion disease that progresses slowly over years. Presents with cerebellar ataxia and dysarthria, sometimes extrapyramidal features followed by dementia