HIV and AIDS Flashcards
HIV is a:
non transforming retrovirus of the lentivirus subfamily
what are the two main subtypes of HIV
HIV-1 and HIV-2
which type of HIV is more common and where are they both found
- HIV-1: sub-saharan Africa - more common
- HIV-2: West Africa
which type of HIV has a slower disease course
HIV-2
what percentage of eastern and southern africa are infected with HIV
54%
more than ______ people have been infected with HIV and ______ have died from AIDS
70,000,000; 35,000,000
an estimated ______ people across the globe are newly infected with HIV each year
2.7 million
the vast majority of people infected with HIV are in ______ countries
low and middle income
aprroximately ______ people in the US are living with HIV today
1.2 million
the CDC indicates there are ______ new HIV infections each year
38,000
the rate for males was ______ than the rate for females
5 times higher
new HIV diagnosis was highest among people aged:
25-44
what is the largest single risk factor for HIV
male to male sexual contact
what body fluids can HIV be transmitted through
blood, semen, breast milk and vaginal secretions are the main fluids that have shown to be associated with the transmission of the virus.
- can also be found in tears, saliva, CSF, amniotic fluid and urine
transmission of HIV is by:
exchange of infected bodily fluids predominantly through intimate sexual contact and by parenteral means
HIV infection can occur through:
oropharyngeal, cervical, vaginal and GI mucosal surfaces, even in the absence of mucosal disruption
infection with HIV is aided by the presence of other:
sexually transmitted diseases that can produce mucosal ulceration and inflammation
the most common method of sexual transmission in the US is:
anal intercourse in men who have sex with men in whom the risk of HIV infection is 40 times higher in other men and in women
_______ is the second most common form of transmission in the US
heterosexual transmission
transmission from _____ is the third largest group affected in the US
sharing needles
why is transmission by oral fluids rarely seen
saliva contains a number of HIV inhibitory factors which appear to reduce the ability of the virus to infect its target cells
what are the key antigenic components in HIV
- gag
- pol
- env
- p17
-p24
-p7
-p66/51
-p32
-p11
what are the regulatory proteins for viral replication in HIV and accessory proteins in HIV
- regulatory proteins: Tat and Rev
- accessory: Nef, Vif, Vpu,Vpr
what is the cell cycle in the pathophysiology of HIV
entry -> replication -> release
describe the entry phase in the pathophysiology of the HIV virus
- HIV mainly infects cells with CD4 cell-surface receptor molecules (CD4+ T helper lymphocytes mainly) at the site of HIV entry
- infected is aided by langerhans cells in mucosal epithelial surfaces which can become infected delivering HIV to underlying T cells resulting in dissemination to lymphoid organs
- the virus uses CD4+ cells to gain entry by fusion with a susceptible cell membrane or by endocytosis
- the probability of infection depends on the number of infective HIV virions in the body fluid which contacts the host and the number of cells with appropriate CD4 receptors available at the site of contact
describe the replication phase of the pathophysiology of HIV
- once in the cell the viral particle uncoats from its spherical envelope to release its RNA
- the enzyme product of the pol gene, a reverse transcriptase that is bound to HIV RNA, synthesizes linear double stranded cDNA that is the template for HIV integrase
- it is this HIV proviral DNA which is then inserted into the host cell genomic DNA by the integrase enzyme of the HIV
describe the release stage of the pathophysiology of HIV
- just before the budding process, HIV protease cleaves Gag proteins into their functional form which gets assembled at the inner part of the host cell membrane and virions then begin to bud off
- nucleocapsid (NC) protein interacts with the RNA within the capsid
- Capsid (Ca) protein surrounds the RNA of HIV
- Matrix (MA) protein surrounds the capsid and lies just beneath the viral envelope
- the cells HIV selects for replication are soon “swell and burst” by caspase-3-mediated apoptosis (5%), the remaining greater than 95% of quiescent lymphoid CD4 T cells die by caspase-1 mediated pyroptosis triggered by abortive viral infection
- the spectrum of HIV disease changes as CD4+ cell count declines
what is seroconversion
the transition from the point of viral infection to when antibodies of the virus become present in the blood (circulating antibodies)
what are the CDC stages of HIV infection in adults and adolescnts
- stage 1: immediately after HIV exposure and may last for years
- stage 2: progressive immunosuppresion and early symptomatic disease
- stage 3: AIDS, variety of immunosuppression related diseases
describe stage 1 of HIV
- lab confirmation of HIV infection
- no AIDS defining conditions and CD4+ T lymphocytes count greater than 500 cells/microL
- or CD4+ T lymphocyte percentage of total lymphocytes of greater than 29
describe stage 2 HIV infection
- laboratory confirmation of HIV infection
- no AIDS defining condition
- laboratory confirmation of HIV infection and CD4+ lymphocyte count of 200-499 cells/microL
- or CD4+ T lymphocyte percentage of total lymphocytes of 14-28
describe stage 3 HIV infection
- lab confirmation of HIV infection and CD4+ T lymphocyte count is less than 200 cells/microL
- or CD4+ T lymphocytes percentage of total lymphocytes is less than 14
- or documentation of an AIDS defining condition
- documentation of an AIDS defining condition supercedes a CD4+ T lymphocyte count of greater than 200 cells/microL and CD4+ T lymphocytes percentage of total lymphocytes of greater than 14
the average normal CD4 percentage for someone who is HIV negative is about: and the normal range is:
40%; 25-65%
during the first 2-6 weeks after initial infection with HIV:
70% of patients dvelop acute flulike sympotms marked by viremia
what are the symptoms of stage 1 HIV like
- mononucleosis like
- lymphadenopathy
- fever
- pharyngitis
- weakness
-diarrhea - nausea
-vomitting - myalgia
- headache
-weight loss - skin rash
a _____ in CD4+ cells occurs with high levels of plasma HIV
drop
how long does it take for the body to make antibodies against HIV
between 6 and 12 weeks
how long can the latent asymptomatic period last
8-10 years
what is happening in the latent period
virus disseminates throughout lymphoid tissue, incubates, replicates and alters many physiologic processes, resulting in hyperimmune activation, persistent inflammation and impaired gut function and flora
- progressive decline in immune function evident as progressive depletion of CD4+ cell count and increase in viral load
- silent clinically except for persistent lymphadenopathy
what is happening in the early symptomatic period/stage 2 and how long does it last
1-3 years
- viral load continues to increase
- CD4+ count drops below 500
- viral load increases more
-platelet decreases in 10% of pts
what are the symptoms in the early symptomatic period for HIV
- persistent generalized lymphadenopathy
- fungal infections
- vaginal yeast and trichomonal infections
- oral hairy leukoplakia
- HSV
- herpes zoster
- HIV related retinopathy
- constitutional symptoms: fever, night swets, fatigue, diarrhea, weight loss, weakness
what happens in stage 3 AIDS
- CD4+ count drops to below 200 cells or documentation of AIDS defining condition
- platelet counts low
- opportunistic infections
- neutrophil count may be low
- CD4+ cell count less than 50 and high risk for lymphoma and death
what are the malignancies associated with stage 3 HIV
- kaposi sarcoma
- burkitt lymphoma
- non hodgkin lymphoma
- primary CNS lymphoma
- invasive cervical cancer
-carcinoma of rectum - slim disease
what is a normal ratio of CD4 and CD8 cells
between 1 and 4
what are the 3 types of HIV tests available
- nucleic acid tests
- antigen/antibody tests
- antibody tests
CD4+ and CD8+ cell counts should be performed when
at the time of HIV diagnosis and every 3-4months after
HIV tests are performed on:
blood or oral fluid and sometimes urine
what do nucleic acid tests test
- viral load
- detect HIV sooner than other tests
when is the greatest viral load found in HIV
during the first 3 months after initial infection and during the late stages of the disease
what do antigen/antibody tests detect
both HIV antibodies and antigens in the blood
in HIV infected individuals _____ is produced even before antibodies begin to develop
p24
antibody tests detect:
antibodies to HIV in blood or oral fluid
more rapid tests and the only approved HIV self tests are:
antibody tests
what are the lab tests ordered in medical setting for HIV diagnosis
first ELISA
- second ELISA
- all positive results are then confirmed with western blot analysis
the combination of ELISA tests and western blot are accurate more than _____ of the time and the aptients are considered_______
99%; potentially infectious
what is the drug therapy recommended for HIV
antiretroviral medications
what is the ARV medication
three drug regiment
what is virologic failure defined as
a confirmed viral load greater than 200 copies/mL in the presence of ART
what is pre exposure prophylaxis
- a way for people who do not have HIV but who are at high risk of getting it to prevent it
- the pill (Truvada) contains two medicines
- when someone is exposed to HIV through sex or injection drug use, these medicines can work to keep the virus from establishing permanent infection
what is the management of infants born to women with HIV
all infants should receive postpartum ARVs to reduce the risk of perinatal transmission of HIV
the average dental practice is predicted to encounter _____ pts infected with HIV per year
at least 2
in the US _____ of individuals who have acquired HIV are unaware of their status, contributing to as high as ____ of continuous HIV spread
15%; 40%
what is the incidence of HIV transmission from infected patients to health care workers? and how
0.3% - through a needlestick or sharp instrument contaminated with the virus
the risk of infection from a needlestick is _____ for hep b and _____ for hep C
30%, 3%
the CDC recommends ___________ after exposure to HIV infected blood
postexposure prophylaxis (PEP) as soon as possible
when should tests for seroconversion be done after HIV exposure
3,6 and 12 months
what are standard precautions
a set of infection control practices used to prevent transmission of diseases that can be acquired by contact with blood, body fluids, non intact skin and mucous membranes
the CDC and ADA recommend the infected dentist:
inform their patients of their HIV serostatus and should receive consent or refrain from performing invasive procedures
what are the 2 major considerations in dental treatment for patients living with HIV/AIDS
- current CD4+ lymphocyte count
- level of viral load
patients with greater than 350 CD4+ count:
dental treatment in no different than any other pt if the HIV pt has no symptoms
patients who are symptomatic for the early stages of AIDS have increased suscpetibility to infection and may need:
AB prophylaxis
patients with AIDS can receive almost any dental care needed after the possibility of _________ has been ruled out
significant immunosuppression, neutropenia, thrombocytopenia
what is the prevalance of persistent generalzied lymphadenopathy
70%
PGL consists of:
lymphadenopathy that has been present for more than 3 months and involves two or more extralingual sites
what are the most commonly involved extralingual sites in PGL
posterior and anterior cervical, submandibular, occipital, and axillary nodes
nodal enlargement in PGL is:
usually larger than 1 cm and varies from 0.5-5cm
what is indicated with PGL
lymph node bioppsy
PGL _____ of progression to AIDS; _______ of untreated patients will have diangostic features of AIDS within 5 years
does warn; one third
what is the histo of PGL
florid follicular hyperplasia
what is the most common intraoral manifestation of HIV infection
candidiasis
what is the most common organism in oral candidiasis
candida albicans
about ______ of HIV infected individuals and more thaN _____ of patients with AIDS develope oral candidiasis at some point in their disease course
one third; 90%
what candidiasis appears when the CD4 count is less than 200
pseudomembranous candidiasis
what candidiasis appears when CD4+ is below 400
erythematous candidiasis
what are the types of candidiasis seen with HIV and AIDS
- pseudomembranous
- erythematous
- hyperplastic
- angular chelitis
oral candidiasis can cause:
pain, reduction in taste and smell which may lead to decreased food intake and further wasting
what is the tx for oral candidiasis with HIV
- nystatin is ineffective
- topical clotrimazole is effective but has high rate of recurrence
- systemic fluconazole and itraconazole are effective but have a lot of drug interactions and may result in drug resistant candidiasis
- if azoles fail, then IV amphotericin B can be administered
what is a SE of amphotericin B
nephrotoxicity
what is the most common EBV related lesion in patients with AIDS
oral hairy leukoplakia
EBV is associated with several forms of_____ in HIV infected patients
lymphoma
OHL in HIV infected patients is a sign of:
severe immunosuppression and advanced disease
OHL clinically presents as:
a white mucosal plaque that does not rub off.
- most cases occur on the lateral border of the tongue and range in appearance from faint, white vertical streaks to thickened, furrowed areas of leukoplakia with a shaggy surface
what is the histology for oral hairy leukoplakia
- thickened parakeratin
- epithelium is acanthotic and exhibits a bandlike zone of lightly stained cells with abundant cytoplasm (ballon cells) in the upper spinous layer
- characteristic pattern of peripheral margination of chromatin termed nuclear beading
- dysplasia is not noted
when definitive diagnosis is needed, demonstration of EBV can be achieved by:
in situ hybridization, PCR, immunohistochemistry, southern blotting or electron microscopy
mucosal, cutaneous and or nail hyperpigmentation may be induced by:
- a variety of drugs taken by HIV/AIDS patients such as zidovudine and emtricitabine based HIV regiments
- drugs used to control microbial infections in these patients such as ketoconazole, clofazimine, and pyrimethamine
- destruction of the adrenal cortex by disseminated infections in this immunocompromised population is another possible cause of the observed hyperpigmentation
- pigmentation with no apparent cause has arisen in HIV infected patients
what is the tx for hyperpigmentation
- usually no tx
- single lesions may have to be biopsied so that melanoma can be ruled out
- patients with adrenal insufficiency may require corticosteroids
where is linear gingivitis found
a distinctive linear band of erythema that involves the free gingival margin and extends 2-3mm apically
linear gingivitis dx should be reserved for:
gingivitis that does not respond to improved plaque control and exhibits a greater degree of erythema than would be expected for the amount of plaque present
linear gingivitis results from:
an abnormal host immune response to subgingival bacteria or may represent an unusual pattern of candidiasis
necrotizing ulcerative gingivitis appears as:
ulceration and necrosis of one or more interdental papillae with no periodontal attachment loss
patients with NUG have:
interproximal gingival necrosis, bleeding, pain and halitosis
necrotizing ulcerative periodontitits is characterized by:
gingival ulceration and necrosis associated with rapidly progressing loss of periodontal attachment
what is seen in NUP
- multiple isolated defects
- edema, severe pain, spontaneous hemorrhage
necrotizing stomatitis may be seen as:
an extension of NUP or may involve oral mucosa separate from the gingiva
necrotizing stomatitis involves mainly:
soft tissue or extends into the underlying bone resulting in extensive sequestration
how is linear gingivitis treated
debridement, povidone iodide irrigation, chlorhexidine mouth rinse, and/or antifungal medication
what is the tx for NUG and NUP
debridement, antimicrobial therapy, pain management, immediate follow up care, long term maintenance
how is NUG and NUP maintained long term
- chlorhexidine
- after initial debridement, removal of additional diseased tissue should be performed within 24 hours and again every 7-10 days for two to three appointments, depending on the patients response
- montly recalls are necessary until process stabilizes
- evaluations then are performed every 3 months
the prevalence of oral recurrent HSV infection among HIV individuals increases significantly once the CD4+ cell count is:
less than 50
within the setting of HIV infection, recurrent herpetic lesions may be:
widespread, occur in an atypical pattern and persist for months
herpes labialis may extend to:
the facial skin and exhibits extensive lateral spread
what is one accepted definition of AIDS with HSV
persistence of active HSV infection for more than one month in a patient infected with HIV
what is the tx for HSV
- systemic acyclovir, valacyclovir, or famciclovir for at least 5 days
- higher doses may be needed during immunosuppression
- an elixir or syrup of diphenhydramine of 1.25mg/5mL can be used for pain control
among patients with HIV infection, herpes zoster is often:
severe, with increased morbidity and mortality rates
how old are varicells zoster virus patients
younger than 40 years
in patients with well controlled HIV disease, herpes zoster usually is confined to:
a single dermatome but persists longer than usual
in full blown AIDS ______ of varicella zoster is not unusual
dissemination to multiple dermatomes
severe intraoral involvement of varicella zoster virus may lead to:
bone sequestration and loss of teeth, these sequelae may be delayed a month or more after the intitial onset of herpes zoster
what is the treatment for varicella zoster virus lesions
- valacyclovir 1g PO tid; famciclovir 500mg PO tid, acyclovir 800mg PO 5 times per day
- IV acyclovir may be needed for severe herpes zoster in patients with immunosuppression
- routine zoster vaccination for HIV infected patients is not recommended currently, however zoster vaccination may be considered for those with well controlled HIV disease with CD4+ counts greater than 200
HIV associated salivary gland disease can arise anytime during HIV infection and is considered:
a localized manifestation of diffuse infiltrative lymphocytosis syndrome
DILS is characterized by:
CD8+ lymphocytosis with diffuse lymphocytic infiltration of various sites such as the major or minor salivary glands, lacrimal glands, lungs, kidneys, muscles, nerve and liver
what is the main clinical sign of DILS
salivary gland enlargement, particularly affecting the parotid. bilateral involvement is seen in about 60% of cases and often is associated with cervical lymphadenopathy
what is a variable finding in DILS
xerostomia
what is the tx for DILS
oral prednisone and antiretroviral therapy
describe recurrent aphthous stomatitis
- most lesions are major and herpetiform
- with more severe reduction of CD4+ cells, major lesions are more common
- lesions that are chronic or atypical or dont respond to tx should be biopsied
- treatment invovles potent topical or intralesional corticosteroids. systemic steroids generally are avoided to prevent further immunosuppression
describe HIV related oral ulceration
a distinct entity not corresponding to any pattern of recurrent aphthous stomatitis nor caused by fungal, bacterial , or viral organisms
antiretroviral therapy can ____ oral ulceration
induce
most HPV lesions arise in:
the anogenital region
what are the benign HPV lesions
oral squamous papilloma, verruca vulgaris, condyloma acuminatum, and multifocal epithelial hyperplasia
what areas of the mouth are most commonly involved in HPV infections
labial mucosa, tongue, buccal mucosa, and gingiva
what do the lesions in HPV look like
a cluster of white, spikelike projections, pink cauliflower like growths or slightly elevated sessile papules
what is the histo for HPV infections
- can be sessile or papillary and covered by acanthotic or hyperplastic stratified squamous epithelium
- epithelium demonstrates vacuolization of numerous epithelial cells and occasionally may exhibit mild variation in size of nucleus
- dysplasia has been noted within HPV related lesions in patients with AIDS and mandates close observation for development of squamous cell carcinoma
- koilocytosis
what is the tx for HPV infections
- surgical excision is most common
- surgical methods are associated with frequent recurrence
- electrocautery and laser ablation may expose the surgical team and patient to a plume containing infectious HPV
what is the associated with lymphoma and reduction in CD4+ lymphocytes
lack of an effective immune response in patients with AIDS contributes to the increase in malignant disease that has been associated with AIDS including kaposi sarcoma, lymphoma, and carcinoma
what is the most common malignancy among the AIDS population in the US
non hodgkin lymphoma
most cases of NHL represent
high grade, aggressive B cell neoplasms
oral lesions in AIDS related NHL most frequently involve:
the gingiva, palate and tongue
what is the radiographic presentation of NHL
widening of the periodontal ligement and loss of lamina dura
Kaposi sarcoma most likely arises from:
endothelial cells which may express markers for both lymphatic and blood vessel differentiation and is caused by HHV-8
what are the 4 clinical presentations of kaposi sarcoma
- classic
- endemic
- iatrogenic
- epidemic (AIDS related)
what is the second most common malignancy with AIDS
kaposi sarcoma
in western countries kaposi sarcoma is related to
the sexual transmission of HHV8
in kaposi sarcoma high titer of _____ have been found in saliva
HHV8
what is required for dx of kaposi sarcoma
a biopsy
relative to the general population HIV infected individuals have an estimated twofold increased risk of developing ______
oral cavity and pharyngeal cancer
oral SCC tends to occur at a ______ among HIV infected individuals
a younger age
what is the tx for oral SCC
surgical resection, radiation therapy, and/or chemotherapy
most HIV patients with a dx of oral SCC have:
advanced disease and an unfavorable prognosis
what is the clincial dx for oral SCC
- SCC
- deep fungal infection
- TB
- atypical lymphoproliferative disorder