L8: viral infections pt 2

Question 1

what kind of cells does EBV affect

Answer 1

immortalises b cells and remains in host for life (latent)

Question 2

ebv is hhv what

Answer 2

hhv 4

Question 3

how does ebv spread?

Answer 3

via bodily fluids (saliva, blood, semen)

Question 4

what is known as the kissing disease?

Answer 4

infectious mononuleosis, which is brought about by ebv (hhv4)

Question 5

what are the symptoms of infectious mononucleosis?

Answer 5

person infected with ebv wil have infectious mononucleosis
- lymphadenopathy, hepatosplenomegaly, thrombocytopenia, aplstic anemia
- pharyngitis, rhinitis, cough, rash
- fatigue, malaise

Question 6

symptoms of infectious mononucleosis is more pronounced in who

Answer 6

older px

Question 7

associated conditions with ebv infection:

Answer 7

• OHL
• lymphoproliferative disroders eg burkitts lymphoma
• nasopharyngeal carcinoma
• salivary lymphoepithelial carcinoma
• sarcoma

Question 8

what is an eg of lymphoproliferative disorder?

Answer 8

burkitts lymphoma

Question 9

oral presentation of ebv

Answer 9

• necrotizing ulcerative gingivitis (NUG)
• mucosal petechiae

Question 10

how to dx ebv?

Answer 10

• full blood cell count - if got lymphocytosis (increase in absolute lymphocyte count)
• clinically
• serology (paul bunnell test to detect heterophil antibodies)
• serology (indirect immunofluorescent test for ebv specific AB - done if the PB test is negative)
• ELISA and recombinant DNA derived Ag test

Question 11

what is the paul bunnell test used to detect and what infection does it detect?

Answer 11

detects heterophil antibodies which are Ig that agglutinate sheep erythrocytes
used as a rapid test for ebv

Question 12

tx for ebv

Answer 12

supportive care via:
- antipyretics
- non aspirin nsaid
- not rec to use AB in cases with tonsilitis
- not rec to use corticosteroid unless there is life threatening symptoms like airway obstruction (due to enlarged tonsils and adenoids)
- antiviral agents (but only temporary resolution of OHL)

Question 13

primary cmv infection is mostly in what type of ppl

Answer 13

infancy – through placenta, breastfeeding

adolescence - sexual activity

Question 14

recurrent cmv infection is mostly in what types of ppl

Answer 14

immunocompromised

Question 15

cmv lies latent in what

Answer 15

endothelial cells mainly, also got lymphocytes, macrophages and salivary glands

Question 16

cmv spreads via what

Answer 16

body fluids like saliva and blood

Question 17

which virus is present in 40% of 30 year olds, and 80-100% of 60 year olds?

Answer 17

cmv

Question 18

tx of cmv

Answer 18

• most resolve spontaneously
• symptomatic relief can be provided by NSAIDs
• immunocompromised px: give anti virals like ganciclovir and valganciclovir
• in immunocompromised, can also give cART (combination antiretroviral therapy) to improve immune status

Question 19

histopatho findings of cmv

Answer 19

owl eye cells (swollen infected cells)
aka reed sternberg cells

Question 20

in what type of infection do we see owl eye cells

Answer 20

cmv

Question 21

what types of cells do hhv 6, 7, 8 target?

Answer 21

6 and 7 target t lymphocytes
8 targets b lymphocytes and endothelial cells

Question 22

which virus is a common cause of childhood acute febrile illness?

Answer 22

hhv 6

Question 23

what are the types of enteroviruses?

Answer 23

• coxsackie virus (type A and B)
• echo virus

Question 24

characteristics of enteroviruses:
- is it widespread and contagious?
- what kind of outbreak does it cause?
- what kind of diseases caused?

Answer 24

• widespread and highly contagious
• cause epidemic outbreaks
• wide spectrum of diseases but mostly self limiting

Question 25

where are the lesions of hfmd?

Answer 25

- hand and foot: around fingers toes and heel margins - oral lesions in labial and buccal mucosa, vestibules, tongue, palate

Question 26

which lesions are painless and which are painful in hfmd?

Answer 26

those on hands and feet are painless, those in oral cavity are mild to moderate pain

Question 27

what are the descriptions of lesions of hfmd on the skin and the oral lesions?

Answer 27

skin is firm raised NODULES, painless oral lesions are multiple small ULCERS, mild to moderate pain

Question 28

how to dx hfmd?

Answer 28

clinical presentation: will have prodromal flu like symptoms before lesions develop - immunofluorescence or culture

Question 29

mx of hfmd?

Answer 29

supportive and palliative **** (these are KEYWORDS) - give lots of fluids, can give anesthetics and analgesics - monitor for systemic complications/ systemic disease

Question 30

how long does hfmd last

Answer 30

usual course is 7-10 days

Question 31

hfmd caused by what kind of virus

Answer 31

enterovirus - coxsackie A16

Question 32

how does hfmd spred?

Answer 32

via faecal oral route

Question 33

herpangina caused by what virus?

Answer 33

enterovirus -- coxsackie A1-6, A8, A10, A22

Question 34

what are some systemic symptoms of herpangina?

Answer 34

sore throat, dysphagia, fever, malaise, headahce

Question 35

description of herpangina lesions

Answer 35

multiple small 2-3mm ulcers red macules -> fragile vesicles then rapidly ulcerate

Question 36

how long do herpangina lesions take to heal?

Answer 36

7-10 days

Question 37

location of herpangina lesions

Answer 37

posterior oral cavity/ oropharynx if we see some lesions elsewhere, it is unlikely herpangina

Question 38

how to dx herpangina?

Answer 38

- clinical presentation - viral culture, immunofluoresnce

Question 39

mx of herpangina?

Answer 39

- supportive and palliative for symptomatic cases - can give anesthetics and analgesics

Question 40

histo patho findings of herpangina - _____ and _______ oedema that form intraepithelial ______ - vesicle enlarges and ruptures through ________ layer to form _______ vesicle - epithelial ____ and ______ - inclusion bodies and multinucleated epithelial cells _______

Answer 40

- intracellular and intercellular oedema that form intraepithelial vesicle - vesicle enlarges and ruptures through epithelial basal cell layer to form subepithelial vesicle - epithelial necrosis and ulceration - inclusion bodies and multinucleated epithelial cells absent

Question 41

histopatho findings of herpangina - intracellular and intercellular _____ that form ______ - vesicle enlarges and _____ through epithelial basal cell layer to form _____ - _______ _____ and ulceration - ________ bodies and _______ epithelial cells absent

Answer 41

- intracellular and intercellular oedema that form intraepithelial vesicle - vesicle enlarges and ruptures through epithelial basal cell layer to form subepithelial vesicle - epithelial necrosis and ulceration - inclusion bodies and multinucleated epithelial cells absent

Question 42

ddx of herpangina?

Answer 42

hfmd (similar clinical findings) to differentiate, hfmd usually has more lesions and involve anterior oral cavity more, whereas herpangina is posterior oral cavity

Question 43

what type of virus got more than 100 strains identified but we only need to focus on a few?

Answer 43

hpv need to focus on hpv 6 and 11 (benign ) hpv 13, 32 (focal epithelial hyperplasia) and 16, 18, 31, 33 and 35 (squamous cell carcinoma)

Question 44

are the hpv oral lesions contagious?

Answer 44

mildly contagious, require direct mucosal contact

Question 45

hpv lies latent in what cells

Answer 45

epithelial cells

Question 46

hpv infect what type of cells? how?

Answer 46

infect keratinocytes via - viral DNA incorporation into host DNA - E6&7 genes induce transformation of cell

Question 47

what HPV associated with focal epithelail hyperplasia?

Answer 47

hpv 13, 32

Question 48

what HPV associated with SCC?

Answer 48

16, 18, 31, 33 and 35

Question 49

what HPV associated with proliferative verrucous leukoplakia (benign)?

Answer 49

6, 11

Question 50

verruca vulgaris is which hpv?

Answer 50

2,4

Question 51

mx of hpv?

Answer 51

- biopsy to identify virus is recommended before removal - removal of hpv lesions can be done by: conservative surgical excision, co2 laser (which vaporises lesion) cryotherapy (liquid nitrogen) electrosurgery chemical tx but there will be high rate of recurrence of lesions

Question 52

what are the chemical tx avail for hpv lesions? -

Answer 52

- podophyllotoxin 0.5% gel - interferon alpha (INF-a) * rmb this one, is an intra lesional injection - imiquimod cream/ soln

Question 53

histopatho findings of HPV - proliferation of _____ arranged in ____ like projections, with ________ CT cores - ______ (viral altered epithelial cells) present in spinous cell layer

Answer 53

- proliferation of keratinised squamous epithelium arranged in finger like projections, with fibrovascular CT cores - koilocytes (viral altered epithelial cells) present in spinous cell layer

Question 54

histopatho findings of HPV - proliferation of ______ squamous epithelium arranged in finger like projections, with __________ - koilocytes (_______ cells) present in ______ ___ layer

Answer 54

- proliferation of keratinised squamous epithelium arranged in finger like projections, with fibrovascular CT cores - koilocytes (viral altered epithelial cells) present in spinous cell layer