ID: viruses Flashcards

Question

Varicella Zoster (HHV-3): - what dz does it cause - transmission--how long is someone contagious--start to end - prodrome? - classic evolution of the rash? - PE... hallmark? - diagnosis--- best one? - tx: immunocompetent vs immunocomp - prevention

Answer 1

Primary: varicella --->chicken pox Reactivation: herpes zoster-->shingles CHICKEN POX: * transmission=aerosol droplets or direct contact * *contagious 48 hours prior to the onset of the rash up until ALL the lesions have crusted over*** Prodrome: * fever * malaise * anorexia and/or pharyngitis followed by------>generalized vesicular rash usually w/in 24 hours RASH: evolution * *start as erythematous macules-->papules-->vesicular (crops)-->crust over * *starts on face-->trunk-->spreads to extremities * ***pruritic **** DEW DROPS ON A ROSE PETAL PE: **HALLMARK= maculopapules, vesicles, and scabs in various stages of evolution Diagnosis: * ***clinical * *but can do a 1. Tznack smear= take scraping from the vesicle and will see MULTI NUCLEATED GIANT CELLS 2. VZV DNA via PCR 3. Immunofluorescent detection of viral antigen in lesions or culture 4. serologic tests * **BEST TEST IS PCR *** TX: 1. health children <12 YO= supportive and sympto tx--tylenol and calamine lotion--NO NO NO NSAIDS it can cause superinfection 2. Adults/adolescents >12, and immunocomp: Acylovir to help prevent complications--- win 72 hrs of onset * avoid contact with pregnant women PREVENTION: 1. Varicella (VAR) vaccine: live attenuated * 1st dose=12-15MO * 2nd dose=4-6 YO

Answer 2

ASA because it can lead to Reye Syndrome

Answer 3

NSAIDS--- can risk superinfection

Answer 4

1. bacterial superinfection MC in kids due to itching - ->staph aureus - ->staph pyogenes 2. Varicella pneumonia leading cause of mortality and morbidity in adults (3-7 days after rash)

Answer 5

after primary infection with Varicella zoster-- virus remains latent in the DRG or cranial nerve ganglia---- where it can reactivate RF: 1. normal aging.. >50 YO 2. poor nutrition 3. immunocompromised status * **can occur in younger PT too CM 1. prodrome of fever, malaise, sensory changes (PAIN, burning, paresthesias) 2. followeed by painful eruption of vesicles on erythematous base 3. unilateral rash within a single dermatome---does not cross the midline--MC thorax * *Zoster ophthalmicus: opthalmic branch of trigeminal nerve (CNV) is involved---- can cause blindness in absence of tx ********HUTCHINSON's SIGN******* * *Ramsay Hunt Syndrome: facial nerve (CN-VII) pain and vesicles appear in external auditory canal--lose sense of taste in anterior two thirds of tongue + ipsilateral facial palsy Diagnosis: 1. clinical 2. if need to confirm: best test is PCR 3. Tzanck smear does NOT differentiate b/w chicken pox and shingles... not best choice TX 1. Acyclovir, Valacyclovir, famicilovir * **Valacyclovir used MC bc of the dosing 2. Analgesics for pain--narcotics for serious cases 3. can be transmited until all the lesions crust over PRevention: the following are both good for 5 years 1. recombinant vaccine (RVZ): adults >50 YO, 2 doses * **second dose is given 2-6 MO after first 2. Zostavax: live attenuated vaccine--no longer in US

Answer 6

CN VII-- facial nerve

Answer 7

trigeminal nerve...CN V-- the opthalmic branch

Answer 8

1. post-herpetic neuralgia= persistent pain/sensory symps >90 days-----MC 2. cranial neuropathies/CNS involvement

Answer 9

Infectious Mononucleosis---HHV-4 MC early childhood---second peak late adolescence by adulthood--- more than 90% have been infected and have antibodies also assoc with Hodginks disease, t cell lymphoma and other tumors infects B cells--causes them to proliferate----CA transmission: "kissing disease" * close contact of infected secretions--saliva CM: 4-6 week incubation pd 1. young children may be asympto or can have mild pharyngitis +/- tonsillitis 3. adolescents: 75% present as infectious mono--TRIAD **Lymphadenopathy--MC is posterior cervical **Splenomegaly (wk 2-3) **exudative pharyngitis PRODROME before triad: extreme fatigue, fever, HA, ***if PTs get ampicillin + mono= RASH* diagnosis: * Lab work: lymphocytosis with >10% atypical lymphocytes--Downey cells - elevated LFTs - elevated billi *heterophile antibody test (monospot) --done week 3 is the TOC TX: 1. supportive measures--rest, analgesia 2. increased risk of splenic rupture-->avoid contact sports*******

Answer 10

MC congenital viral infection assoc with developmental defects and hearing loss transmission: close contact or sexual transimssion, body fluids, blood, organ transplantation, placenta, breastmilk CM: 1. primary infection: most are asympto * if symptom: similar to EBV w/o sore throat or lymphadenopathy 2. reactivation: immunocompromised patients * colitis: diarrhea, fever, abd pain, bloody stools--MC * Retinitis: decreased vsual acuity and floaters (imp cause of blindness in AIDS) * esophagitis: odynophagia with large superficial ulcers on upper endoscopy diagnosis: * atypical lymphocytosis, heterophile antibody NEGATIVE * negative monospot test * pathology: intracellular inclusions surrounded by a clear halo--- "owl eye cells" TX: 1. primary dz for immunocompetnet= supportive 2. tx for reactivation * Ganciclovir is first line and TOC * others: Foscarnet, Cidofovir, Valacyclovir 3. HIV PT w/ CD4< 50 cell/uL-->Valganciclovir is given prophylactically

Answer 11

Valganciclovir if CD4<50

Answer 12

HHV-6 * common childhood disease * trans via resp droplets MC in 9-12MO CM: **HIGH fever, over 104 sometimes--lasting 3-5 days **other than fever--- child appears fine **fever will resolve abruptly before onset of rash RASH: rose pink, maculopapular, blanchable rash, begins on the trunk and neck-->moves to face--lasts up to 2 days Diagnosis: clinical TX: - supp - self limitng

Answer 13

Parovirus B19 Fifths dz trans: respiratory droplets, percutanous exp to blood, crosses placenta Pregnancy: cytotoxic effect on fetal RBCs--severe anemia and CHF, spontanous abortions, hydrops fetalis CM: 1. begins with flu like symp 2. then a rash--- "slapped cheeck" 3. then: erythematous maculopapular rash on proximal extremities (usually arms and extensor surfaces) and trunk--- fades into classic lacelike reticular pattern rash * *rash can return from overheating in the sun, hot baths or stress Diagnosis: -clinical TX: * Symptomatic * self limiting

Answer 14

Rubeola Paramyxovirus ***one of the most contagious directly transmitted pathogens transmission: resp droplets CM: 1. prodrome (3 C's) * *Cough * *coryza--nasal discharge * *Conjunctivitis 2. Koplik spots--bluish grey grain of salt with red halo 3. followed by a macular rash and fever--starting on the HEAD/HAIRLINE and spreading downwards--palms and soles diagnosis: * Clinical * confirmatory: serology MC: either one is a + test 1. + measles virus-specific IgM in a single specimen of serum or oral fluid 2. fourfold or greater increase in measles virus-specific IGG antibody levels 3. PCR***** tx: 1. supportive care 2. superinfection preventions * Vit A high doses * ribavirin--in cases of pneumonia * Mealses immune globulin (if high risk PT) ``` Prevention MMR vaccine-- live attenuated 2 doses 1st: 12-15 MO 2nd: 4-6YO ```

Answer 15

encephalitis ---rare pneumonia--mc of mortality

Answer 16

Togavirus respiratory transmission CM: 1. prodrome: low grade fever, cough, anorexia, lymphadenopathy (posterior cervical, posterior auricular) 2. RASH: pink or light pink nonconfluent maculopapular rash starting on the FACE and spreads to the trunnk and extremities----rash is usually first symptom * **rash lasts 3 days 3. Forchheimer spots: petechia on soft palate Diagnosis: * diff to diagnose clinically bc the rash looks similar to other dz 1. Serologic testing--rubella specific IgM OR a 4-fold increase in rubella-specific IGG antibody titer 2. viral culture TX: * supportive * Prognosis: not assoc with complications in children (compared to rubeola) * BUT it is teratogenic in first trimester Prevention: MMR 1st: 12-15MO 2nd: 4-6 YO

Answer 17

Rubeola-- measles

Answer 18

Rubeola or measles

Answer 19

Rubella or german measles

Answer 20

Paramyxovirus transmission= respiratory droplets, fomites, saliva *was MC in 5-9... now MC in college students ``` CM *low grade fever *malaise *HA *myalgias *anorxia +parotid gland swelling + pain--usuually bilateral in 48 hours ``` diagnosis: clinical Labs: incr amylase complications: 1. Orchitis--inflamm of testicle(s)-- usually unilateral 2. encephalitis 3. meningitis 4. pancreatitis--MC infectious cause of pancreatitis in kids Prevention: MMR--two doses 1st=12-15MO 2nd=4-6YO

Answer 21

Rhabdoviridae infection of the CNS--- encephalitis of the gray matter is 80% * paralytic dz is 20% trans from infected saliva of rapid animal bites--ZOONOTIC DZ *dogs, cats, bats, raccoons, skunks, foxes, coyotes, groundhogs (only rodent) CM PRODROME: *Pain *parathesia *itching at bite site--hallmark CNS phase: encephalitis, hydrophobia (painful laryngospasm after drinking---seeing or hearing water is bad), numbness, paralysis "rapid rage" and hypersalivation respiratory phase= paralysis of resp muscles--DEATH diagnosis: NEGRI BODIES in the brain--- seen on autopsy negri bodies=eosinophilic cytoplasmic inclusions composed of rabies virus proteins and viral RNA *diagnostic TOC= direct fluorescent antibody testing from bisy of specimen of skin from the nape of the neck TX: *no effective management once symptoms start--- pts rarely survive EXPOSURE: 1. first episode: Rabies vaccine AND rabies Immune Globulin (RIG) * vaccine---if healthy: days 0, 3, 7, 14, (add 5th dose, day 28 if immunocomp* * RIG----half direclty into the wound and surrounding areas... other 1/2 IM distal frm wound 2. second exposure or more: vaccine alone on days 0 and 3--NO immunoglobulin

Answer 22

1. measles/rubeola 2. mumps 3. Rubella/german measles

Answer 23

worldwide epidemics--pandemics

Answer 24

major outbreak of influenza

Answer 25

mild respiratory

Answer 26

<5 and >64

Answer 27

pregnant elderly children

Answer 28

A >>>B for more severe outbreaks transmission= resp secretions--sneezing, couhgin, talking, breathing, or fomite CM: * *ABRUPT ONSET of the following 1. fever/chills 2. muscle/body aches--MC legs and lumbosacral 3. HA 4. sore throat 5. cough * s/s usually spontaneously resolve 4-7 days Diagnosis: * rapid influenza nasal swab--high specificity and fast * clinical * gold standard=viral culture (takes 3-7 days) or RT-PCR * if secondary infection is present-- order CXR TX: given w/in 48 hours of onset of s/s **mostly supportive but can give antivirals THREE DRUGS FDA APPROVED FOR A and B: 1. Oseltamivir (tamiflu) PO **** DOC for anyone even pregnant/elderly/hospitallized/complicated infections 2. Zanamivir--inhaled nose 3. Peramivir--IV M2 inhibitors: given within 48 hours of onset of s/s 1. Amantadine*** 2. Rimantadine * **act only against influenza A * *high resistance to these drugs---not recc for tx or prophylaxis

Answer 29

* pneumonia * resp failure * meningitis * myocarditis * encephalitis * rhabdo * Kidney failure * death

Answer 30

antivirals and tx influenza A and B Oseltamivir (tamiflu) PO **** DOC for anyone even pregnant/elderly/hospitallized/complicated infections 2. Zanamivir--inhaled nose 3. Peramivir--IV

Answer 31

tx influenza A only 1. Amantadine **** 2. Rimantadine * **act only against influenza A * *high resistance to these drugs---not recc for tx or prophylaxis

Answer 32

Prevention 1. chemoprophylaxis-->antivirals if contact with infected 2. Influenza vaccine--ANNUALLY for everyone >6MO who dont have contraindications **contains both A and B strains **two types avail in US: A) inactivated vaccine--70% efficiacy B) A live, attenuated vaccine--recc for kids with 90% efficacy, 85% in adults, given intranasally--NEVER GIVE TO PREGNANT OR IMMUNOCOMP

Answer 33

HSV-2 | the other 10-20% is HSV-1

Answer 34

RF: 1. female > male 2. AA > caucasians 3. new sexual partner 4. infrequent condom use 5. MSM CM: * PRIMARY INFECTION 1. prodrome of systemic features--Fever, HA, malaise, localized pain and itching, dysuria, or tender lymphadenopathy 2. then painful genital ulcers: starts as erythematous lesions then develops into groups of vesicles and pustules * RECURRENT INFECTION * MC with HSV-2 and immunodeficient PT * presentation LESS SEVERE, with fewer lesions and shorter duration (7-10days) * but can occur very frequently up to 10X/yr * recurrence usually decrs over time PE: * multiple, shallow, tender ulcers * grouped vesicles on an erythematous base * inguinal lymphadenopathy Diagnosis: * *TOC is PCR-- msot sensitive and specific * direct microscopy--Tzank smear-->multinucleated giant cells and +/- eosinophilic intracellular inclusions * direct fluorescent antibody or type-specific serologic tests (Gold stand)---but not as sensitive/specific as PCR TX: 1. antivirals: Acyclovir**, valacyclovir** or famciclovir 2. first episode: PO acyclovir (5x/day) or valacyclovir (BID) 3. recurrent: PO acyclovir (TID) and valacyclovir (BID) * *can also give the antivirals daily for suppression

Answer 35

*****16 *****18 31 33

Answer 36

benign tumors of squamous cells--- warts

Answer 37

trans=skin to skin contact, including genital contact infects squamous epithelial cells CM: * *serotypes 1-4** 1. skin warts--hands, fingers, soles of feet **serotypes 6, 11, 16, 18** 1. condylomata acuminata--soft, fleshy, cauliflower like lesions, most are asympto but can be: +itching +burning +pain and +tenderness ***6 and 11: koilocytes aka gential warts ]**16 and 18: preneoplastic and can progress to squamous cell carcinoma diagnosis: * clinical * Can do PCR or biospy of lesion TX: 1. wart removal--cryoablation with liquid nitrogen, topical Imiquimod and Podofilox are PT applied at home vs Podophyllin, Bichloroacetic acid and Trichloroacetic acid are clinical applied 2. prevention: *Gardasil 9--> first dose age 10--12 and 2nd dose 6-12 MO later *if starting after age 15: then 3 doses is reccomended DO NOT GIVE TO PREGNANT OR BF MOMS

Answer 38

6, 11, 16, 18

Answer 39

``` 6 11 16 18 31 33 45 52 58 ```

Answer 40

1. two doses six mo apart 2. three doses: 0, 1-2 MO, and 6 mo 3. three doses: 0, 1-2MO and 6 MO

Answer 41

HIV-1 is found wordwilde HIV-2 is found mainly in western africa both cause AIDS

Answer 42

trans= MC person-person via sex, mother to child during delivery, contact with blood IVDU, needle sticks ***takes a very high dose of HIV to cause infection---why very few HC workers have become sick thru needle sticks*** CM: acute, middle/latent, late/immunodeficiency 1. Acute phase: acute seroconvertion * 2-4 weeks after infection * flu-like or mononcleosis-like illness: * fever * lethargy * sore throat * gen lymphadenopathy * Maculopapular rash on trunk, arms, and legs * ****readily transmissible bc high viral load**** 2. middle/latent phase (chronic phase) * usually measured in years * if untx-->latent period lasts for 7-11 yrs * pateints usually asympto----but large amt of HIV is being produced * AIDS-related complx (ARC)-->fever, fatige, wt loss and lymphadenopathy 3. Late/immunodeficient *AIDS* *CD4 count below 200 u/uL or a CD4+ T cell percent of total lymphocytes of <14% AND/OR at least 1 AIDS-defining condition-->opportunistic infections two MC infections are: 1. Kaposi's sarcoma 2. Pneumocystis pneumonia

Answer 43

uncircumcised

Answer 44

10-14 days after infections (during the acute phase)

Answer 45

3-4 weeks after infection | this means they have seroconverted

Answer 46

``` Candidiasis *** Crptyococcal meningitis Cryptosporidium Coccidiodomycosis PCP Cerebral toxoplasmosis Histoplasmosis ```

Answer 47

Mycobacterium avium-intracellulare TB Salmonella septicemia Nocardia

Answer 48

Herpes zoster CMV HSV encephalitis

Answer 49

Lymphoma--Burkitt's immunoblastic | Kaposi sarcoma

Answer 50

pre-test counseling: 1. discuss inds for HIV testing 2. risk assessment 3. implications of positive test results 4. discuss confidentiality and F/U Indications for testing 1. screening: test all adolescents and adults at incr risk for HIV and ALL PREGNANT WOMEN 2. any PT with features of chronic HIV infection TESTS: - -->4th generation enzyme immunoassay (EIA) for HIV 1 an 2 * *detects antibodies (3-12 weeks psot infection) and p24 antigen of HIV * *negative result=no further testing * *pos result= --->test HIV-1 and HIV-2 antibody differentiation immunoassay ---> indeterminate results: test with FDA approed HIV-1 nucleic acid test OTHER TESTS 1. Western blot: 2 bands present= positive 2. Reverse transcriptase-polymerase chain reaction (RT-PCR)-->tells you the viral load 3. HBV and HCV serologies--can affect choice of therapy 4. . other sexual transmitted dz 5. CBC, BMP, LFTs, fasting lipid profile, A1c, UA 6. Pregnancy test * antivirlas can afffect liver funct and dyslipidemia and glucoe tolerance, * **basically: - combination of antigen/antibody immunoassay (screening) + HIV viral load testing (RT-PCR)

Answer 51

early HIV | *getting a second postiive virologic test will suggest HIV infection

Answer 52

early or established infection **confirm this with a second test: repeat HIV RNA or serologic test weeks later

Answer 53

1. HIV-1 and HIV-2 antibodies that appear 3-12 weeks after infection 2. p24 antigen of HIV

Answer 54

immune function of HIV PT

Answer 55

viral core protein that appears in the blood as the viral RNA level rises following HIV infection

Answer 56

viremia | *pronostic marker in long-term management

Answer 57

1. Viral RNA load--indicator of antiretrovirl therapy response: decr viral load indicates effective tx 2. CD4+ T cell count: increases with antiretroviral tx

Answer 58

Antiretroviral therapy for ALL patients * *highly active retroviral therapy (HAART) is mainstay in US * *over 26 drugs * *6 major classes MC ones are: 1. Nucleoside Reverse Transcriptase Inhibitor (NRTI) 2. Non-nucleoside reverse transcriptase inhibitor (NNRTI) 3. Integrase strand transfer inhibitor (INSTI) 4. Protease inhibitor Regimens for newly diagnose PT: *2 different NRTIs + INSTI POST-EXP Prophylaxis: 1. within 72 hours of exposure--3 drug regimen x28 days PRE-EXP Prophylaxis: 1. reduce the risk in uninfected high-risk individuals * 2 drug regimen

Answer 59

PCP | Bactrim DS

Answer 60

Histoplasmosis if endemic area | Itraconazole

Answer 61

Toxoplasmosis Bactrim DS and Cryptococcus Fluconazole

Answer 62

MAC Azithro or Clarithro and CMV Retinitis Valganciclovir

Answer 63

CD4 count <200 cells/uL | recurrent and life threatening opportunistic infectinos or malginancies occur

Answer 64

CD4 count <200 OR AIDS-defining illness like Pneumocystis pneumonia