Flashcards in Micro - Virology (Herpesviruses) Deck (34)
Name 7 major Herpesviruses.
(1) HSV-1 (2) HSV-2 (3) VZV (4) EBV (5) CMV (6) HHV-6 (Note: HHV-7 is less common cause of same condition as HHV-6) (7) HHV-8
What are the 2 routes of transmission for HSV-1?
Respiratory secretions, saliva
What 4 diseases result from HSV-1 infection?
(1) Gingivostomatitis (2) Keratoconjuctivitis (3) Temporal lobe encephalitis (4) Herpes labialis
What is the most common cause of sporadic encephalitis in the US, and what virus causes it?
Temporal lobe encephalitis; HSV-1
Where are the following herpesviruses latent: (1) HSV-1 (2) HSV-2 (3) VZV (4) EBV?
(1) Trigeminal ganglia (2) Sacral ganglia (3) Dorsal root or trigeminal ganglia (4) B cells
What 2 diseases result form HSV-2 infection?
(1) Herpes genitalis (2) Neonatal herpes
What 3 diseases result from VZV infection?
(1) Varicella-zoster (chickenpox, shingles) (2) Encephalitis (3) Pneumonia
Where is latent HSV-1 found?
Latent in trigeminal ganglia
Where is latent HSV-2 found?
Latent in sacral ganglia
Where is latent VZV found?
Latent in dorsal root or trigeminal ganglia
What are the 2 routes of transmission for HSV-2?
Sexual contact, perinatal
What is the route of transmission for VZV?
What are the 2 routes of transmission for EBV?
Respiratory secretions, saliva
What infectious disease is caused by EBV? What 4 symptoms characterize it?
Mononucleosis. Characterized by fever, hepatosplenomegaly, pharyngitis, and lymphadenopathy (especially posterior cervical nodes).
How is EBV transmitted? What is another name for this infection, and why?
Transmitted by respiratory secretions and saliva; also called "kissing disease" since commonly seen in teens, young adults.
What 2 herpesviruses share the same 2 routes of transmission? What are those 2 routes of transmission?
(1) HSV-1 (2) EBV; Respiratory secretions, saliva
What are the 6 routes of transmission for CMV?
(1) Congenital (2) Transfusion (3) Sexual contact (4) Saliva (5) Urine (6) Transplant
What 4 diseases result from CMV?
(1) Congenital infection (2) Mononucleosis (negative Monospot) (3) Pneumonia (4) Retinitis
What is the characteristic histologic finding associated with CMV infection?
Infected cells have characteristic "owl's eye" inclusions
Where is latent CMV found?
Latent in mononuclear cells
What is characteristic of mononucleosis due to CMV infection?
Negative Monospot (unlike EBV, which is positive Monospot)
What is the route of transmission for HHV-6?
Transmitted by saliva
What is the route of transmission for HHV-8?
What disease does HHV-6 cause? How does it present?
Roseola: high fevers for several days that can cause seizures, followed by a diffuse macular rash
What disease does HHV-8 cause, and in what patient population is it seen?
Kaposi's sarcoma, a neoplasm of endothelial cells. Seen in HIV/AIDS and transplant patients.
What is the test of choice for identification of HSV in the following contexts: (1) Skin/genitalia (2) Herpes encephalitis?
(1) Viral culture for skin/genitalia. (2) CSF PCR for herpes encephalitis.
What sample is taken for a Tzanck test? What does it detect? What virus is it used to identify?
A smear of an opened skin vesicle to detect multinucleated giant cells; HSV Identification; Think: "Tzanck heavens I do not have herpes"
Again what finding does the Tzank test detect, and in what conditions is this finding seen? What is another finding seen in these conditions but not detected by Tzanck test?
Tzanck test - a smear of an opened skin vesicle to detect multinucleated giant cells, HSV identification; Infected cells also have intranuclear Cowdry A inclusions
Aside from mononucleosis, with what other diseases/conditions is EBV associated?
Also associated with development of Hodgkin's and endemic Burkitt's lymphomas as well as nasopharyngeal carcinoma
What is the most common complication of shingles?
Most common complication of shingles is post-herpetic neuralgia
What cell type does EBV infect? Along those lines, what are the cell findings of EBV infection on peripheral blood smear?
Infects B cells. Atypical lymphocytes seen on peripheral blood smear are not infected B cells but rather reactive cytotoxic T cells
What kind of test is used for EBV infection? More specifically, what is detected by this test, and how?
Positive Monospot test; Heterophile antibodies detected by agglutination of sheep or horse RBCS.
Besides mononucleosis, what are 3 other conditions associated with EBV infection?
Associated with (1) Hodgkin lymphoma, (2) Endemic Burkitt lymphoma, (3) Nasopharyngeal carcinoma.