Infectious Flashcards
Constituents of herpesviridae
HSV1/2 (HHV1/2)
VZV (HHV3)
EBV (HHV4)
CMV (HHV5)
HHV8
After HSV, reverse alphabetical order
Name prion diseases
CJD
Gerstmann-Staussler-Scheinker syndrome
Fatal familial insomnia
Kuru
Variant CJD
Define prion
Infectious agents composed of misfolded proteins that cause transmissible neurdegenerative disorders
Pathogenesis of prion disease
Normal protein undergoes conformational change to abnormal form (now resistant to protease digestion)
Infectious/misfolded prion protein binds to normal conformation protein, catalyzing misfolding into prion protein
Prion protein buildup causes spongiform encephalopathy
Methods by which prion disease arise in humans
Acquired
Familial
Sporadic
Differentiate classic and variant CJD
Classic CJD: “Florid plaques” absent, protease resistance prion proteins variable accumulation, infective agent NOT seen in lymphoid tissue
Variant CJD: “florid plaques” present, protease resistance prion proteins significant accumulation, infective agent seen in lymphoid tissue
CJD classification
Classic
Sporadic
Iatrogenic
Familial
Variant
Prion disease IHC
Proteinase K-resistant PrP(Sc)
Baltimore classification of viruses with example of each
dsDNA - herpesviruses
ssDNA - parvovirus B19
dsRNA - reovirus
(+)ssRNA - West Nile Virus
(-)ssRNA - rabies
ssRNA-RT - HIV
dsDNA-RT - HepB
Oncogenic viruses with associated malignancies
HBV - HCC
HCV - HCC
Human T-lymphotrophic virus - Adult T-cell
EBV - Burkitt, Hodgkin, PTLD, NPC, Gastric CA
HHV-8 - Kaposi sarcoma, multicentric Castleman, primary effusion lymphoma
HPV - cervical CA, anal CA, penile CA, vulvar/vaginal CA, oropharyngeal SCC
Types of low risk HPV
6, 11, 42, 43, 44, 54, 60, 61, 72
Types of high risk HPV
16, 18, 31, 33, 39, 45, 51, 52, 56, 58, 59, 66, 68, 73
HPV carcinogensis
E6 protein binds p53 preventing its function (cell cycle arrest and apoptosis)
E7 protein binds RB leading to p16 overexpression
Histologic findings of acute viral hepatitis
Hepatocyte ballooning and apoptosis with resulting ceroid-laden macrophages
Cholestasis
Zone 3 lymphocytic infiltrate
Mixed portal inflammation
Specific histologic features of chronic HBV and HCV
HBV - ground-glass hepatocytes
HCV - lymphoid aggregates and reactive bile ducts, focal macrovesicular steatosis
Define fulminant hepatic failure
Hepatic insufficiency progressing from symptom onset to encephalopathy within 2-3w outside the setting of chronic liver disease
Routes of transmission for HepA-E
HepA: fecal-oral
HepB: parenteral, vertical
HepC: parenteral
HepD: nonparenteral or parenteral (needs HepB infxn)
HepE: Fecal-oral
Protocol for needle-stick injury during an autopsy
Follow facilities policies and procedures
Wash wound with soap and warm water
Allow wound to bleed, do not squeeze
Apply antiseptic if necessary
Contact occupational heath or ED ASAP
Clinical presentation for infectious mononucleosis
Fever
Fatigue
Lymphadenopathy
Splenomegaly
Sore throat
Maculopapular rash
Splenic findings in infectious mononucleosis
Enlarged spleen
Soft/fleshy with hyperemic cut surface
Red pulp congestion and hyperplastic white pulp
Blurred red/white pulp border
Complications/symptoms of HIV with decreasing CD4 counts (cells/mm^3)
<500: B symptoms, mucocutaneous lesions (oral hairy leukoplakia, Kaposi, VZV/HSV), lymphoma, candidiasis, TB
<200: PJP PNA, Toxo, Bartonella, Visceral Kaposi, disseminated fungal infection (Crypto, Coccidioides, Histo)
<100: PML 2’ JC virus, CNS toxo
<50: MAC, CMV, Invasive aspergillosis, bacillary angiomatosis (Bartonella), CNS lymphoma
Pathogen and stain for: Erythema chronicum migrans
Borrelia burgdorferi
Gram neg, WS, Dieterle stain
Helicobacter heilmanii vs pylori
Heilmanii: acquired from domestic animals/pets, larger size, corkscrew morphology, sit freely in gastric foveolar lumen, less associated inflammation
Pylori: Acquired from humans, smaller with seagull morphology, adherent to epithelium, more inflammation/activity
Pathogen and stain for: Bacillary angiomatosis
Bartonella family
Gram neg, WS
