Viruses - DNA - Herpes Family Flashcards
TORCHeS Infections
TORCHeS Infections:
Toxoplasmosis
Other (HIV, VZV, Parvovirus B19, enteroviruses, others)
Rubella
Cytomegalovirus
Herpes
Syphilis
Herpes Virus Family
Viruses in the Herpes family
Herpes Virus Family
- Herpes Simplex Virus 1 (HSV1) aka HHV1
- Herpes Simplex Virus 2 (HSV2) aka HHV2
- Varicella Zoster Virus (VZV) aka HHV3
- Epstein–Barr Virus (EBV) aka HHV4
- Cytomegalovirus (CMV) aka HHV5
- Roseola aka HHV6
- Kaposi’s sarcoma-associated herpesvirus (KSHV) aka HHV8
Herpes Virus Family
Are all enveloped or nonenveloped?
Herpes Virus Family
All of the Herpes Virus Family are:
*** Enveloped ***
Herpes Virus Family
The members of the Herpes Virus Family can be found latent in?
(ALL CAN GO LATENT!!!)
Herpes Virus Family
- Herpes Simplex Virus 1 (HSV1) in trigeminal ganglia
- Herpes Simplex Virus 2 (HSV2) in sacral ganglia
- Varicella Zoster Virus (VZV) in dorsal root ganglia
- Epstein–Barr Virus (EBV) in B-cells
- Cytomegalovirus (CMV) in mononuclear** cells** (lymphocytes and macrophages)
- Roseola in monocytes
- Kaposi’s sarcoma-associated herpesvirus (KSHV) in B-cells
Herpes Simplex Virus 1 & 2 (aka HHV1 & 2)
lab tests
Hermes, the god of herpes
- Linear DS DNA
- Enveloped virus
- Replicates in nucleus (like most DNA viruses)
- Cowdry bodies (intranuclear inclusions that look like targets; Large red and eosinophilic)
- Tzanc smear (older test, scrape ulcer base) to look for multinucleated giant cells
- PCR for herpes
Herpes Simplex Virus 1 & 2 (aka HHV1 & 2)
ddx HSV vs. Pox virus inclusion bodies
Hermes, the god of herpes
- HSV:
Cowdry bodies (intranuclear inclusions that look like targets; Large red and eosinophilic)
- ddx vs. Pox virus:
Has similar inclusion bodies but located in the cytoplasm (Guarneri inclusion bodies)
Herpes Simplex Virus 1 & 2 (aka HHV1 & 2)
Source
Hermes, the god of herpes
Transmitted by Sex, saliva, and vertically (TORCHeS infection!)
- HSV 1:
Usually confined to the upper half of the body
- HSV 2:
Usually confined to the genital regions
Herpes Simplex Virus 1 & 2 (aka HHV1 & 2)
HSV 1 (aka HHV1)
(Usually confined to the upper half of the body)
*** 1st infects as gingivostomatitis (AKA Orolabial herpes; inflammation of the oral mucosa and gingiva) ***
Hermes, the god of herpes
- Snake like ulcers
- Herpes rash (rose petal & dew drops; clear vesicles on a erythema base)
- Lip herpes; Cold sores!!!
- Ocular herpes; Keratoconjuctivitis (* fluorescent stained slit lamp exam of cornea)
- Temporal lobe encephalitis*w/bizarre behavior; Hemmorages and necrosis!
- Herpetic whitlow; Herpes on finger (dentists!!!)
- 1-2 weeks after infection can cause an erythema multiforme rash.
* (#1 cause of sporadic encephalitis)
Herpes Simplex Virus 1 & 2 (aka HHV1 & 2)
HSV 2 (aka HHV2)
(Usually confined to the genital regions)
Hermes, the god of herpes
- Painful vesicular lesions w/ inguinal lymphadenopathy
- Can cause aseptic meningitides (mostly in adolescents and adults
- Herpetic whitlow; Herpes on finger (dentists!!!)
- 1-2 weeks after infection can cause an erythema multiforme rash.
Herpes Simplex Virus 1 & 2 (aka HHV1 & 2)
HSV erythema multiforme rash
Hermes, the god of herpes
- 1-2 weeks after infection with HSV 1 or 2 (mostly 1)
- looks like targets!
- Starts on hands and feet and moves inwardly / centrally
- Due to a hypersensitivity rxn.
Herpes Simplex Virus 1 & 2 (aka HHV1 & 2)
Treatment
Hermes, the god of herpes
- NO CURE
- Prevent breakouts with Acyclovir and / or valcyclovir
Epstein-Barr Virus (aka HHV4)
lab tests
Ye Olde Epstein Bar
- DS DNA
- Enveloped virus
- Cytotoxic (CD8+) T-cell reactive* lymphocytes
* (Downy cells** AKA **atypical cells; Very large, lots of cytoplasm, have oval, indented, or folded nucleus)
- Monospot Ig* test to diagnose during acute infections → activates B cells to secrete heterophile sheep antibodies that agglutinate sheep or horse RBC’s.
* (IgM for current or recent infection, IgG for prior infections)
Epstein-Barr Virus (aka HHV4)
MOA
Ye Olde Epstein Bar
- EBV envelope (glycoprotein) binds to CD21 receptor (Complement receptor type 2 aka CR2; on the surface of B cells) to infect B cells.
- T-cells proliferate → causing splenomegaly*
- Most are reactive cytotoxic CD8+ T cells (reactive lymphocytosis) aka downy cells or atypical cells but can also be NK cells.
* (Must avoid contact sports due to risk of splenic rupture)
Epstein-Barr Virus (aka HHV4)
Source
Ye Olde Epstein Bar
- Spread through mouth secretions
- “KISSING DISEASE!!!”
- Causes infectious mononucleosis (“mono”)
Epstein-Barr Virus (aka HHV4)
signs and symptoms
Ye Olde Epstein Bar
- Triad of symptoms:
- fever
- pharyngitis (mono pharyngitis often in teens and adults, vs. strep pharyngitis more often in children)
- lymphadenopathy (often tender lymphadenopathy in posterior cervical region)
- Can also see Splenomegaly**
Epstein-Barr Virus (aka HHV4)
EBV ↑ the risk factor for 3 cancers!
Ye Olde Epstein Bar
- Hodgkin’s lymphoma (HL); mixed cellularity
- Non-Hodgkin’s lymphoma (NHL); Burkett lymphoma
- Nasopharyngeal carcinoma (NPC)
- Also ↑ risk of Oral Hairy leukoplakia (but its NOT a precancerous lesion)
Epstein-Barr Virus (aka HHV4)
EBV ↑ the risk factor for 3 cancers!
1) Hodgkin’s lymphoma (HL); mixed cellularity
Ye Olde Epstein Bar
- Weakend immune systems develop B cell lymphoma.
- The cancerous B cells are an abnormal type called Reed-Sternberg cells (giant cells that resemble “owl eyes”).
- Mixed cellularity is the second most common type of HL and is seen mostly in older adults (although it can occur at any age).
- It can start in any lymph node but most often occurs in the upper half of the body.
Epstein-Barr Virus (aka HHV4)
EBV ↑ the risk factor for 3 cancers!
2) Non-Hodgkin’s lymphoma (NHL); Burkett lymphoma*
* (The fastest growing human tumor, associated with impaired immunity and is rapidly fatal if left untreated.)
Ye Olde Epstein Bar
- Burkitt lymphoma is a form of non-Hodgkin’s lymphoma in which cancer starts in B-cells.
- Especially likely to develop in people infected with HIV.
- Common translocation is t8:14
- Endemic (African) Burkitt lymphoma is common in young children who have both malaria and EBV. It usually starts as tumors of the jaw or other facial bones. It also can affect the GI tract, ovaries, and breasts and can spread to the CNS
- The types more common in the U.S. (sporadic and immunodeficiency-associated) usually start in the bowel and form a bulky tumor mass in the abdomen, often with massive involvement of the liver, spleen, and bone marrow.