DD Common viral pathogens Flashcards
List what type of virus they are: DNA vs RNA Herpes simplex type 1 (HSV1) Herpes simplex type 2 (HSV2) Varicella zoster virus (VZV) Cytomegalovirus (CMV)
All are DS DNA!
Which virus targets Mucosal epithelium and
Est. latency in sensory ganglia?
Herpes simplex type 1 (HSV1)
Herpes simplex type 2 (HSV2)
Varicella zoster virus (VZV)
CMV cellular target for primary infection and latency
Epithelia, monocytes, lymphocytes, others
EBV cellular target for primary infection and latency
B lymphocyte, epithelia
Transmission of:
CMV
Contact, blood transfusions, transplantation, congenital
Transmission of:
EBV
Saliva
Clinical presentation of HSV1 and 2
Orofacial lesions and Genital lesions, Encephalitis, Herpes Whitlow, Herpes keratitis, Neonatal herpes
For immunocompromised indiv with CMV what treatment would you use?
ganciclovir
When virus enters host, it brings with it Immediate Early (IE) genes, which are required for expression of Early (E) and Late (L) genes.
What are the functions of E and L genes?
□ E genes encode proteins involved in DNA replication, such as viral DNA polymerase, thymidine kinase (TK), helicase, etc.
□ L genes encode structural proteins, such as capsid and glycoproteins.
Describe the differences in disease manifestation for HSV-1 vs HSV-2 when you know that they both result in the development of painful mucocutaneous ulcers
® HSV-1 is primarily responsible for orofacial and ocular lesions
® HSV-2 generally is transmitted sexually and causes genital disease
Assume skin vesicles in neonate less than 1 month of age is due to?
HSV
Chickenpox aka _______________
Shingles aka __________________
What do they have in common?
• Chickenpox, which is called varicella.
§ Chickenpox is the result of a primary infection with VZV.
• Shingles, which is sometimes called herpes zoster or “zoster”.
§ Shingles is caused by reactivation of VZV.
serious complications of chickenpox
- Secondary infection or cellulitis
- Pneumonia
- Necrotizing fasciitis
- Encephalitis or encephalomyelitis
- Hepatitis
- Congenital varicella syndrome
- Typically in immunocompromised indivs.
Which chicken pox complication is most common? Second most common?
- Secondary infection or cellulitis
2. Pneumonia
What bacteria is associated with:
- Secondary infection or cellulitis
- Pneumonia
- Necrotizing fasciitis
- Secondary infection or cellulitis
- Group A Strep - Pneumonia
- GAP
- Staph aureus - Necrotizing fasciitis
- Group A Strep
Chance that preggo Mom can pass CMV to her baby
Via reactivation or primary infection (more common)
She develops primary infection → gets viremia → baby is infected ⅓ of the time, of those, 10-15% will have symptoms at birth = 3-5% (Math is hard) have congenital CMV
how can CMV can be diagnosed histologically in infected tissue?
□ CMV-infected cells will have a characteristic “owl’s eye” appearance
® The owl’s eye is a dense, dark nuclear body surrounded by a halo. These represent intranuclear inclusions (accumulation of viral proteins or virions). There may also be smaller intracytoplasmic inclusions noted.
Importance of serology in diagnosing CMV
In primary CMV disease, serology can establish the diagnosis.
AND
can distinguish between primary and recurrent infection.
Interpret Serology:
Negative IgG
Negative IgM
Never had CMV
IgM indicates recent disease
(IgG remains for life)
Interpret Serology:
Positive IgG
Negative IgM
Had previous infxn of cmv
IgM indicates recent disease
(IgG remains for life)
Interpret Serology:
Positive IgG
Positive IgM
Recent reactivation of cmv
IgM indicates recent disease
(IgG remains for life)
Interpret Serology:
Negative IgG
Positive IgM
Primary CMV
IgM indicates recent disease
(IgG remains for life)
