4th Exam - Viral Diseases Flashcards
Viral affinity for one cell type:
tropism
Consequences of viral infection:
no injury, tissue destruction, inflammation, weaken host defense, cell proliferation, neoplasia
Virus that causes tissue destruction:
Hep B
What causes tissue destruction in Hep B infection?
immune-mediated, not the virus
Infiltration type with viral infections:
lymphocytic
Viral infection often leads to:
bacterial infection
Case: pregnancy, illness at 7wks gestation, small head, cataracts, heart murmer:
Rubella infection during pregnancy
Define teratogenic:
induce birth defects
Developing fetus, most vulnerable to intrauterine infection during this period:
1st trimester
Is the fetus primarily or secondarily infected in congenital rubella syndrome?
secondarily
Evidence of active congenital rubella syndrome infection at birth:
none, no inclusion bodies, no inflammation
Main symptoms of baby born with congenital rubella syndrome (CRS):
microcephaly, ventricular septal defects, cataracts, microencephaly, deafness
Part of brain most commonly affected in CRS:
cerebrum
Hep B transmission:
Parental route (any body fluids) or as STD
Hep B virus is found here:
blood, body fluids
6 forms of Hep B infection:
subclinical, acute, fulminant (wide spread necrosis of liver), persistent infection, hepatocelllular carcinoma, AI vasculitits (pts w history of Hep B, like pts w PAN)
AI vasculitis connected to Hep B infection is related to this disease:
PAN
Pre-icteric phase (HBV)
Anorexia, fever, fatigue
Icteric phase:
jaundice, hepatomegaly, 90% recovery
TF? HBV is cytolytic.
F. body’s immune system goes against its hepatocytes (immune-mediated)
How do a person’s cytotoxic T cells kill hepatocytes in HBV?
T cell rec binds cell w both HBcAg (Hep B core antigen: usually indicates person is infectious) and Class 1 MHC, T cell releases perforins, punctures cell membrane, cell dies
Infection type assoc w PMN’s:
bacterial
Indicative of viral lymphocytosis:
Lymphocytic inflammation, Antibody producing B cells, T cells
Smoldering HBV infection with lymphocytic inflammation:
piecemeal necrosis, edges of portal zones chewed up – cirrhosis –> hepatoma
Arterial lesions of a person w AI vasculitis contain:
HBV, complement, and Ig
What induces the AI response in AI vasculitis?
virus in lesion
Red, generalized, maculopapular rash is assoc w:
Measles
Multiple white lesions are assoc w:
Measles, Koplik spots (pathogneumonic finding)
What cell type is assoc w measles:
PMN
What precedes measles by 2-3d?
rash, Koplik spots, often on buccal mucosa
Pathoognomic for measles:
Koplik spots
What virus causes Hand Foot Mouth Disease?
Coxsackievirus, A16 most often
TF? There is a vaccine for Hand Foot Mouth Disease.
F
Itchy, maculopapular rash that becomes a vesicular, water-filled, lesion later
Hand Foot Mouth Disease
This disease presents similarly to syphilis:
Hand Foot Mouth Disease
Fever is assoc w:
Hand Foot Mouth Disease, Acute Hep, Mumps, Varicella Zoster, Mono
How is the cell killed in acute Hep?
liver cell membranes are altered
TF? The basement membrane is stimulated to make more PMNs in acute Hep.
F. more lymphos
Cause of lymphocytic inflammation in tissue:
Antibody producing b cells, T cells
Smoldering infection is assoc with:
lymphocytic inflammation, piecemeal necrosis, edges of portal zones chewed up
30% of pts w AI vasculitis/ PAN have this in their blood:
HBAg
Arterial lesions of AI vasculitis/ PAN contain:
HBV, complement and Ig
enlargement of the parotid gland, tender, painful to palpation is assoc w:
mumps, usually unilateral
TF? Herpes labialis is assoc w fever.
F
Herpes labialis lays dormant here:
trigeminal neuron