Term
| Of the 25 known herpesviruses, name the 8 that cause human infection: |
|
Definition
| Herpes simplex 1 + 2, Varicella zoster, cytomegalovirus, epstein-barr virus, Kaposi sarcoma-related virus, exanthema subitem virus (HHV 6 + 7) |
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Term
| True or false: HHV (human herpesviruses) are all single-stranded DNA viruses |
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Definition
| False, HHV are double stranded, eveloped DNA viruses |
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Term
| Which class of HHV characteristically cause enlargements of infected cells? |
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Definition
| The beta group, including CMV and HHV6-7 |
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Term
| The alpha group of HHV establish latency in which part of the human body? |
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Definition
| Dorsal sensory ganglia of the central nervous system, includes varicella zoster, HSV1 & 2. |
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Term
| Epstein-Barr virus and Kaposi's Sarcoma-related virus of this group of HHV, establish latency in B and T lymphocytes, respectively |
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Definition
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Term
| True or false: HSV 1 and 2 are almost always spread by sexual contact |
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Definition
| True, HSV1 can be spread by skin-skin contact but mostly sexual contact |
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Term
| True or false: half of people with HSV1 antibodies have no clinical disease |
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Definition
|
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Term
| True or false: Infection with one type of HSV confers little cross-protection to the other type. |
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Definition
| False, there is some evidence of cross-reactivity in antibodies to two with infection by HSV1 |
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Term
The annual incidence of HSV-2 infection is:
A. 10,000 cases
B. 100,000 cases
C. 1 million cases
D. 10 million cases |
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Definition
| C, rare before puberty except in cases of child abuse and higher in women |
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Term
| True or false: asymptomatic shedding is the most common way HSV-2 is spread |
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Definition
| True, 90% of infected persons (genital) are asymptomatic |
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Term
Over the last 4 decades, genital herpes prevalence has:
A. increased
B. decreased |
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Definition
|
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Term
| True or false, HSV-1 can only cause oral herpes and HSV-2 can cause only genital herpes |
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Definition
| False, though most commonly HSV-1causes oral herpes, it can cause genital lesions and vice versa |
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Term
| True or false: asymptomatic shedding is more common in men than women |
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Definition
| False, women are more likely to asymptomatically shed HSV-2 than men |
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Term
| What are some correlates of asymptomatic shedding in women with HSV-2? |
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Definition
| Pregnancy, young age, co-infection with HIV, more recent infection |
|
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Term
| True or false: HSV-2 can be spread via fomites, like a toilet seat |
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Definition
| False, though HSV-2 can live on a toilet seat for up to four hours, but without microabrasions HSV-2 cannot enter the epidermis |
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Term
| Between HSV1 and HSV2, which is more likely to be shed asymptomatically |
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Definition
| HSV2 is more likely to spread asymptomatically |
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Term
| Briefly describe the life cycle of HSV infection |
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Definition
| 1) enters through breaks in the mucoepithelium of the genitalia or mouth 2) moves retrograde along sensory nerve axons to the DRG to establish latency 3) can then move anterograde back to site of initial infection and cause painful blisters or be shed asymptomatically in secretions |
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Term
| This gene in the HSV genome is responsible for establishing latency by preventing apoptosis of the infected cell |
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Definition
| the latency associated transcription gene (LAT) |
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Term
| Of all the immune responses, this arm of the immune response is most responsible for combating HSV and preventing recurrence? |
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Definition
|
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Term
| Following primary infection, what three things usually occur in persons infected with HSV? |
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Definition
| 1) Primary disease following primary infection 2) asymptomatic 3) recurrent disease |
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Term
Choose the correct order of lesion progression in HSV infection:
1) vesicle, papule, pustule, ulcer, healed, crust
2) ulcer, crust, vesicle, papule, healed, pustule
3)vesicle, papule, pustule, ulcer, crust, healed
4) papule, vesicle, pustule, ulcer, crust, healed |
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Definition
|
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Term
| Systemic disease (fever, myalgia etc.) appears only with this type of disease |
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Definition
| Primary infection, primary disease |
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Term
Match each type of infection with its clinical appearance:
- First episode, primary a)lesions/mild
- First episode, non primary b)lesions/mild, one side
- First episode, recurrence c) none
- Symptomatic, recurrence d) lesions/severe, 2 side
- Asymptomatic, infection e)lesions/moderate
|
|
Definition
| 1. d, 2. e, 3. a, 4. b, 5. c |
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Term
| At what point of HSV-2 infection do type-specific antibodies become present in serum? |
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Definition
| During the first episode of recurrence is when most seroconvert, antibodies are absent during primary infection or the first episode of non-primary disease |
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Term
| Though both HSV1 and HSV2 can cause genital infection, which type is 8-10 times more frequently recurring and 2x as likely to reactivate? |
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Definition
|
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Term
| Which HSV type is the most common non-vector borne cause of encephalitis? |
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Definition
| HSV1, always suspect if no evidence of vector borne disease in encephalitis, the virus infects neural cells causing necrosis |
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Term
| Why is HSV infection a cause for concern in immunocompromised patients? |
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Definition
| The lesions can become disseminated and life threatening, spreading to organs like the lungs, liver etc. |
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Term
| In reactivation, lesions are typically (more/less) widespread and severe |
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Definition
| Less, recurrent disease of both types is less severe and fewer lesions are present |
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Term
| What is considered the "gold standard" of HSV diagnosis? |
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Definition
| Viral culture from lesions is considered the most sensitive/specific, but clinical evidence of disease with antibody detection in recurrent disease is acceptable as well, antigen detection better for healing lesions, cytology is not recommended, PCR is preferred for CSF detection of HSV |
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Term
| Acyclovir, famiciclovir, and valacyclovir are all effective in blocking viral DNA replication in different ways, thus limiting recurrences. What class of anti-viral drugs to these belong to? |
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Definition
| Nucleic-acid analogs, can directly block replication by joining viral DNA and stopping replication or blocking enzymes (thymidine kinase) necessary for replication |
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Term
| True or false: anti-virals prevent recurrence but cannot eliminate latency for HSV |
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Definition
| True, drugs should be taken when symptomatic to shorten course as well as to prevent recurrence |
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Term
| What steps can be taken to prevent transmission of HSV? |
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Definition
| Condoms work, no sex when symptomatic, partners should be informed, take acyclovir continuously to limit second infections, though asymptomatic shedding CAN occur while on acyclovir |
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Term
| True or false: population-wide screening for HSV is recommended |
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Definition
| False, only HIV+ persons, patients with a partner who has dx HSV, and pregnant women |
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Term
| HPV belongs to this family of viruses |
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Definition
| Papovavirus, enveloped double-stranded DNA virus |
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Term
| These genes in the HPV genome are involved in DNA replication and regulation of transcription. |
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Definition
| The early genes, E1, E2, E4-E7 |
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Term
| When the viral DNA is encoded into the host genome (gene) is disrupted, leaving (gene) and (gene) unregulated, resulting in cervical neoplasia |
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Definition
|
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Term
| Like HSV1 and HSV2 infection, the most common manifestation of HPV infection is: |
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Definition
|
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Term
| True or False: There are ~60 different types of HPV, and once you have been infected with one you have immunity to all |
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Definition
| False, each type confers its own unique immune response |
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Term
| Which four types of mucosal/genital HPV are considered "high risk" for causing cervical and anogenital cancers? |
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Definition
|
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Term
| "Low risk" HPV may not cause cervical and anogenital cancers, but is responsible for what clinical symptoms? |
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Definition
| Genital warts, laryngeal papillomas (from oral-genital contact), low grade cervical abnormalities |
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Term
| True or false: HPV replicates by inserting its viral DNA into the host genome and using the cell's DNA replication apparatus to reproduce. |
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Definition
| False, after entering the basal keratinocytes in the epidermis, HPV forms an episome (circular DNA in cell's cytoplasm), and as they replicate they spill out into other cells. |
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Term
| True or false: HPV is the most common STI in the United States |
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Definition
| True, by age 50 80% of women will be infected with at least one type of HPV |
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Term
| These two continents have the highest incidence of cervical cancer |
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Definition
|
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Term
| Apart from cervical and genital cancers, what other type of cancer can be caused in men, both hetero and homosexual? |
|
Definition
| Anal cancer, in perhaps 1 in 4 heterosexual men an oncogenic HPV is present |
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Term
| Describe four important points about HPV and HIV |
|
Definition
- Co-infection is common, 58% of HIV+ women have HPV infection
- HIV viral load >100,000 associated with increased risk of HPV infection
- Given HIV+, an abnormal pap occurs more commonly than in HIV-
- The course of HPV disease is more severe in HIV+ women
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Term
| True or false: humans are the only reservoir of HPV |
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Definition
|
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Term
| True or false: HPV cannot be transmitted vertically |
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Definition
| False, it is possible for pregnant women to pass the virus to their babies during childbirth |
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Term
| Why is it difficult to establish the degree of communicability of HPV? |
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Definition
| Since most carriage is asymptomatic, it is difficult to ascertain how the disease is transmitted |
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Term
| This aspect of cervical cancer makes it an attractive target for screening |
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Definition
| It is a long, slow growing cancer |
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Term
| How is HPV infection typically diagnosed? |
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Definition
| Usually visual inspection of warts with a bright light, confirmation is required when dx is unclear, immunocompromised, warts are pigmented, indurated or fixed, the lesions don't respond to tx and persistent ulceration or bleeding |
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Term
| If clinical dx or a pap is inconclusive, what is the diagnostic test for HPV? |
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Definition
|
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Term
This tx for genital warts acts by poisoning the mitotic spindle and causing intense local vasospasm.
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Definition
| Podofilox, though there are concerns around toxicity and carcinogenesis |
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Term
This tx for genital warts stimulates a local immune response at the site of application, resulting in wart regression and resolution of infection.
|
|
Definition
|
|
Term
| Apart from topical tx, what other type of tx can be done in a doctor's office to remove warts? |
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Definition
|
|
Term
| True or false: Condoms are effective in preventing HPV transmission |
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Definition
|
|
Term
| Which antigen does the quadrivalent HPV vaccine target, and what strains is it effective against? |
|
Definition
| L1 capsid antigen, 6, 11, 16, 18 |
|
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Term
| True or false, men should receive the HPV vaccine as well as women 9-26 |
|
Definition
| False, it is not approved for use in men |
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Term
|
Definition
| This is the mite that causes scabies |
|
|
Term
| True or false: only male mites infect the skin in scabies |
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Definition
| False, females only infect the skin, though they do complete their life cycle completely on the human host |
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Term
Scabies infections, approximately 300 million a year, occur most commonly in the:
1) Spring
2) Summer
3) Fall
4) Winter
5) No seasonality |
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Definition
| Winter, thought to be due to crowding |
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|
Term
| What two routes of transmission can the S. scabeii mite use to find a new host? |
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Definition
| Skin to skin contact or contact with fomites like bedding or clothing. Mites can survive up to 36 hours at room temperature |
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Term
| Characterized by hyperkeratosis and pustular lesions, crusted scabies mostly occurs in these populations |
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Definition
| Immunocompromised, either via HIV, autoimmune disease, or prolonged glucocorticoid and cancer therapy |
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Term
| What is the tx for scabies? |
|
Definition
| Permethrin 5% cream, applied topically to the whole body and washed off after 8h |
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Term
| In what settings should strict preventive measures, including mass tx with permethrin be implemented? |
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Definition
| Institutional settings, esp. nursing homes and the like since crusted scabies is more likely to occur and its highly transmissible. |
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|
Term
How long can the pruritis and rash of scabies last after tx is completed?
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|
Definition
|
|
Term
Match each condition with its definition:
1) Urethritis a)dysuria, frequent, hematuria, pyuria, fever, flank pain
2) Prostatitis b) dysuria, discharge
3) Cystitis c)dysuria, frequency, pyuria, fever, perineal pain
4) Pyelonephritis d) dysuria, frequent, hematuris, pyuria
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Definition
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|
Term
| Which micro-organism is the most common cause of UTI in outpatients and inpatients alike? |
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Definition
| Escherichia coli, followed by klebsiella, coag- staph, enterococcus, Proteus and Morganella, Candida is common in inpatients |
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Term
| True or false: UTI is the most common bacterial infectious disease in women |
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Definition
| True, accounts for 7 million office visits, 1 million ER visits and 100K hospitalizations at 1-2 billion dollars in cost anually in the US |
|
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Term
| True or false: In addition to females, UTI is common in older males and young children |
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Definition
|
|
Term
| What two epidemiologic classifications of UTI are important for distinguishing the etiology of the infection? |
|
Definition
| Community-acquired vs. nosocomial/hospital acquired |
|
|
Term
| True or false: Recurrent UTI is most common in females of child-bearing age |
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Definition
| False, 30-50% of children with one UTI will have a recurrence, especially boys <6 months of age |
|
|
Term
| Name seven host factors that increase the risk of a UTI |
|
Definition
- High intercourse frequency
- Oral contraceptive/spermicide use
- Pregnancy
- Diabetes
- Voiding dysfxn
- Anatomical abnormality (vesicoureteral reflux)
- Spinal cord injury
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|
|
Term
| What are some genetic risk factors that increase the risk of UTI? |
|
Definition
| Non-secretors of the ABH blood group antigens, CXCR1 receptor mutations, TL4 (lipopolysaccharide) polymorphism, absence of THP, which binds pili of e. coli |
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|
Term
| What are some virulence factors employed by E. coli? |
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Definition
| FimH protein at tip of Type 1 fimbriae assists in adherence to mucosal epithelium, P fimbria, Pod formation in bladder, urease+ bacteria can cause renal stones which increase risk of UTI |
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|
Term
| Name two risk factors for contracting a UTI in the hospital |
|
Definition
| Indwelling catheter and GU instrumentation contamination, urosepsis occurs in 16% of ICU patients |
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Term
| What are some natural host defenses against UTI? |
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Definition
| Urine, prostatic secretions (men), phagocytic cells, urinary oligosaccharides, THP anti-pili protein, mucopolysaccharide lining of the bladder, urinary Ig, micturition, spontaneous exfoliation of uroepithelial cells detaches bacteria |
|
|
Term
| What are three complications of UTI |
|
Definition
| sepsis (urosepsis), osteomyelitis of the spine, renal stones |
|
|
Term
| True or false: Dx of UTI can be made based on clinical findings |
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Definition
| False, urine culture is diagnostic of UTI, CFU/ml>100k is diagnostic in anyone, if sx are present that >100cfu/ml is likely UTI. Urinalysis can be used rapidly to count leukocytes and dx UTI |
|
|
Term
| What are some preventive measures one can take against UTI? |
|
Definition
| Postcoital voiding, cranberry juice |
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|
Term
| True or false: Bacterial vaginosis results from some disruption of vaginal microflora. |
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Definition
| True, though mechanisms are often unclear |
|
|
Term
| True or false: Candida vaginitis results from overgrowth of Candida albicans, which is rarely found in the normal flora of the vagina |
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Definition
| False, 30% of asymptomatic women are colonized with C. albicans |
|
|
Term
| The etiologic agent of trichomoniasis |
|
Definition
|
|
Term
| True or false: Candidiasis is a difficult disease to study epidemiologically because it is not a reportable disease |
|
Definition
| True, it is not an STD but is responsible for most vaginosis, age is a risk factor |
|
|
Term
| What is the most common NONVIRAL STI in the world, accounting for half of all curable STI's worldwide, according to the WHO |
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Definition
| Trichomoniasis, common in both men and women but higher in women |
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Term
| Along with poorer birth outcomes, cervical cancer, PID and infertility, what is perhaps the most grave consequence of trichomoniasis in women? |
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Definition
| It appears to increase susceptibility to HIV-1 infection |
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|
Term
| Though trichomoniasis can cause non-gonococcal urethritis in men, its most common manifestation is |
|
Definition
| asymptomatic, it is also associated with chronic prostatitis |
|
|
Term
| If left untreated, how long can trichomoniasis persist in an individual? |
|
Definition
|
|
Term
| Unlike trichomoniasis, which increases in prevalence with age, BV is significantly associated with |
|
Definition
| multiple sexual contacts with new partners and having unprotected sex, it is the most common cause of vaginitis in women of childbearing age, other risk factors include IUD and prior pregnancy |
|
|
Term
| BV shares many complications with trichomoniasis, in addition it can cause this non-reproductive system infection |
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Definition
|
|
Term
| The potassium hydroxide Whiff test is useful in distinguishing this type of vaginitis |
|
Definition
| It is negative in candidiasis |
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|
Term
| Commonly, increases in vaginal pH result in increased risk of vaginitis, but a decrease in pH can also result in this type of infection |
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Definition
| Candidiasis, occurs in more acidic environments than bacterial vaginosis and trichomonas infection |
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Term
| Dyspareunia, or pain during intercourse, can occur in vaginitis, but is absent in which type of infection? |
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Definition
| BV, otherwise all three can present with a whitish discharge with a malodorous quality, though the smell isn't present with candidiasis. Candidiasis and trichomonas present more commonly with vulvar erythema than does BV |
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Term
| Metronidazole is typically the first line treatment against all types of vaginitis, but BV and trichomoniasis differ with regards to treating the sexual partner(s) |
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Definition
| Partner tx is not recommended with BV, but is with trichomoniasis, even if the partner is asymptomatic, some candida species are resistante to the -azole antifungal drugs |
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Term
| Probiotics, like lactobacilli in yogurt, are posited to be beneficial in a number of ways, but have demonstrated efficacy in only these two clinical occurrences |
|
Definition
| Abx associated diarrhea (c. diff) and childhood diarrhea due to rotavirus infection |
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Term
| A member of the hepadnavirus family, Hepatitis B, has this type of genetic material. |
|
Definition
| Double stranded DNA virus |
|
|
Term
| Describe the four open reading frames of the HBV |
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Definition
| One codes the E antigen HBeAg and the core antigen, one codes for the envelope glycoproteins (surface antigen), one, Pol, codes the polymerases (DNA and RNA) necessary for viral replication, and the HBX gene plays an important role in hepatocellular carcinoma pathogenesis |
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Term
| This form of the HBV genome is resistant to tx, allowing the infection to stay active in hepatocytes for a long time |
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Definition
| cccDNA, covalently closed circular DNA, can either be transcribed to viral RNA and new copies made from the RNA in the nucleus of the hepatocyte, or go on to make new virions (Dane particles) |
|
|
Term
| True or false: hepatic symptoms of HBV infection are a result of CD8+ T cell response, HBV is not in itself cytopathic |
|
Definition
|
|
Term
| What percent of acutely infected persons with HBV will develop chronic HBV infection? |
|
Definition
|
|
Term
| Which populations are most susceptible to developing chronic HBV infectin? |
|
Definition
|
|
Term
| Other than progressing to cirrhosis and cancer, what are two important extrahepatic sequelae of chronic HBV infection? |
|
Definition
| Glomerulonephritis and polyarteritis nodosa |
|
|
Term
| True or false: HIV positive individuals have an increased risk of contracting HBV when exposed and a 3-fold risk of developing chronic HBV infection |
|
Definition
|
|
Term
| Hepatitis B(D) and C can spread sexually or via serum transfer only, what makes HAV and HEV different in this regard |
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Definition
| Primarily fecal-oral transmission, most common acute hepatitis in US is A, most prevalent is C due to chronic infxn, the vaccines for HAV and HBV have drastically reduced their transmission, HCV has been increasing steadily over the past decades |
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|
Term
| True or false: Antibodies for the HBcAg grant immunity from further infection |
|
Definition
| False, the surface antigen-antibody produces immunity, the core does not but is a marker of past infection, it is the only marker present in the serologic gap where surface antigen is no longer detectable but neither are abx to the surface antigen |
|
|
Term
| In addition to the surface antigen, what other serologic marker indicates HIGH infectivity in an HBV+ person |
|
Definition
|
|
Term
True or false: HBeAg appears after HBsAg and disappears
before HBsAg |
|
Definition
|
|
Term
| How can past infection and immunity be distinguished from vaccination and immunity to HBV? |
|
Definition
| The presence of IgG anti-core antibody indicates past infection, not immunization |
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