HIV/AIDs
AIDS is the end stage of HIV infection. Certain events establish the conversion of HIV infection to AIDS what are they
(1) A markedly decrease T4-cell count from a normal level of 800 to 1200/mm3 and (2) The development of certain cancers and opportunistic infections. In 1993, the CDC devised a classification system involving 2 categories that constitute an AIDS diagnosis. (1)Category 1, 2 or 3 and (2)Category A, B, or C
the decline of AIDS is attributed to
(1) a change in estimating methods used to calculate statistical data (2) educational efforts to decrease behaviors that contribute to HIV infection (3) improved antiretroviral drug therapy
Health teaching
-HIV prevention strategies: sexual abstinence and safer sex practices -Diagnostic screening and counseling -Antiretroviral drug: •drug teaching - compliance! •side effect teaching -Support group and resource referrals Encourage diagnostic screening for those whole behaviors place them at risk for HIV infection.
HIV 2
-Less transmittable; longer interval between virus and AIDS - Western Africa is the primary site of infection.
HIV 1
-Mutates easily and frequently - More prevalent in the United States Most of the time when someone speaks about HIV they are referring to HIV-1.
•High risk factors
-Unprotected sexual intercourse -Multiple sex partners -Sharing IV needles -Nonautologous transfusion Infected mother to infant transmission Certain behaviors increase the risk of acquiring HIV from infectious body fluids (listed on slide). Using a condom, is one of the most effective ways to reduce the risk of HIV infection. Before 1984, blood and blood products were a major source of HIV transmission. HIV screening is done on donated blood.
AIDs
-infectious and fatal disorder that weakens the immune system
Integrase inhibitors
-raltegravir (Isentress) prevent the incorporation of viral DNA into the host cell's DNA by blocking the activity of the integrase enzyme. also may be beneficial for people in salvage therapy
CMV treatment
.Foscarnet (Foscavir), cidofovir (Vistide), and ganciclovir (Cytovene) are used in combination aggressively to treat acute CMV infections. Maintenance drug therapy follows to reduce the potential for future viral activation . Foscarnet is used to treat CMV retinitis and is given by controlled IV infusion. Alterations in renal function, fever, nausea, anemia, numbness in the extremities, and diarrhea are the most common adverse effects.
Progression of HIV infection and development of AIDS
1. HIV 2. HIV particles target helper T cells Immune system responds; virus multiplication is kept in check but helper T cells are still invaded 3. virus particles overcome helper T cells 4. Progression varies according to viral load 5. Killer T cells eventually destroy infected helper T cells 6. Immune system is depressed 7. AIDS
The CDC recommends routine testing for the following populations
All persons aged 13 to 24 years All persons seeking treatment for an STI on each visit All persons initiating treatment for tuberculosis All persons with signs and symptoms or illnesses consistent with HIV infection
treatment of cryptospodium
Azithromycin (Zithromax) or Paromomycin (Humatin) is used.
•Pneumocystis pneumonia: Treatment
Bactrim/Septra
Candidiasis is a yeast infection caused by
Candida albicans. Candidiasis may develop in the oral, pharyngeal, esophageal, or vaginal cavities or in the folds of skin. It is often called thrush when located in the mouth.
Immunosuppressed clients may develop serious diarrhea as a result of infection with a protozoan called
Cryptosporidium . This organism is spread by the fecal-oral route from contamined water, food, or human or animal wastes.
NNRTIs
Delavirdine Efavirenz Nevirapine bind directly to the reverse transcriptase enzyme, thus preventing transcription. They are effective only against HIV-1.
ELISA (enzyme-linked immunosorbent assay)
Detect only HIV antibodies an initial HIV screening test, is positive when there are sufficient HIV antibodies; it also is positive when there are antibodies from other infectious diseases. •The test is repeated if results are positive. •If results of a second ELISA test are positive, the Western blot is performed.
Entry inhibitors
Enfuvirtide (Fuzeon) Maraviroc (Selzentry) stops HIV from attaching to a CD4 T-cell by blocking a coreceptor on the cell's surface. Entry and fusion inhibitors are reserved for HIV-infected people who are resistant or developing resistance to NRTIs, NNRTIs, and PIs. People with less advanced HIV/AIDS may also benefit from the inclusion of maraviroc or enfuvirtide in their drug regimen.
To replicate, which means to produce more copies
HIV becomes a parasite of helper T cells (AKA CD4 cells) . HIV alters the helper T cell's genetic code to make more viral particles
Category B symptoms
HIV positive with conditions attributed to or complicated by HIV infection such as Bacillary angiomatosis Candidiasis (oral, vulvovaginal) persistent, frequent, or poorly responsive to therapy Cervical dysplasia or carcinoma Fever or diarrhea for more than 1 month Hairy leukoplakia Herpes zoster (at least two episodes) Idiopathic thrombocytopenic purpura Listeriosis Pelvic inflammatory disease/tubo-ovarian abscess Peripheral neuropathy
Category A symptoms
HIV positive with one or more of the following: Asymptomatic Persistent generalized lymphadenopathy (swollen lymph nodes) Acute (primary) HIV infection with accompanying illness or history of acute HIV infection
Category C symptoms
HIV positive with one or more of the following: Candidiasis (bronchial, tracheal, lungs, or esophagus) Cervical cancer (invasive) Coccidioidomycosis (disseminated or extrapulmonary) Cryptococcosis (extrapulmonary) Cryptosporidiosis for more than 1 month Cytomegalovirus (other than liver, spleen, or nodes) Encephalopathy (HIV related) Herpes simplex (for more than 1 month) or bronchitis, pneumonitis, esophagitis Histoplasmosis (disseminated or extrapulmonary) Isosporiasis (for more than 1 month) Kaposi's sarcoma Lymphoma, Burkitt's (or equivalent), immunoblastic (or equivalent), brain (primary) Mycobacterium avium complex or Mycobacterium kansasii, disseminated or extrapulmonary Mycobacterium tuberculosis, any site, pulmonary or extrapulmonary Mycobacterium, other species Pneumocystis carinii pneumonia Pneumonia, recurrent Progressive multifocal leukoencephalopathy Salmonella septicemia, recurrent Toxoplasmosis of brain Wasting syndrome
Helper T cells function
Helper T cells recognize antigens and Stimulate B cells to produce antibodies.
Repeated HIV testing should be performed yearly among individuals at high risk for HIV infection such as:
IV drug users and their sex partners Persons who exchange sex for money or drugs Partner of an HIV-infected person Person or partner who has more than one sexual partner since their last HIV test Persons starting a new sexual relationship regardless of a previous negative test result
treatment of candiddasis
Inspection of the mouth, throat, or vagina reveals areas of white plaque that my bleed may mobilized with a cotton-tipped swab. When candidiasis affects structures in the mouth and throat, it can lead to problems with eating and subsequent weight loss. Topical antifungals such as nystatin (Myostatin) are useful for treating oral candidiasis. Clients can swish around mouth and then swallow or available as a lozenger. Vaginal tablets or suppositories are used to treat vaginitis. Example, monistat. Sometimes systemic antifungals such as fluconazole (Diflucan) are required to control candidiasis.
Eventually, individuals infected with HIV present with an opportunistic infection or a form of cancer that is atypical for the person's age and health history such as
Kaposi's sarcoma, a type of connective tissue cancer common among those with AIDS may be noted. Pneumocystis pneumonia - nonproductive cough and SOB Females - abnormal gynecologic problems (abnormal Pap smears, Pelvic Inflammatory Disease, gential warts, persistent vaginitis)
cost of meds
Medications cost as much as $10,000 to $30,000 or more a year
Vaccines that may prevent HIV infection are in clinical trails
Research is progressing on the development of preventive vaccines for HIV-negative people and therapeutic vaccine for HIV-positive people to improve their immune system. In 2012, the FDA approved a clinical trial with a protective vaccine developed by Canadian researchers that uses a modified killed whole virus rather than a live virus. In early testing, the Canadian vaccine stimulated a strong immune response and no adverse effects.
Category 1, 2, or 3 is based on
T4-cell count
S/s cryptospordium
Those infected lose from 10 to 20 L of fluid per day. Diarrhea leads to dehydration and electrolyte imbalance Definitive diagnosis is made by stool testing for ova and parasites
Combination antiretroviral therapy (cART)
Using different mechanisms, the combination of drugs suppresses replication of the virus. The drugs lower the viral load more quickly—sometimes to undetectable levels. Doing so ultimately slows the rate of disease progression, prevents opportunistic infections, and, in turn, lengthens survival. Combination therapy diminishes the rate of viral mutations and prolongs drug effectiveness. Using two or more drugs simultaneously reduces the chance that the virus will develop resistance or cross-resistance. Combination of drugs increases the numbers of healthy helper T-cell lymphocytes because it protects many from becoming infected
Some explanations for long-term survival include the following (rate of progression)
Weak strain of HIV Amount of virus is kept low with stronger-than-normal killer T8 cells Atypical CCR5 or CXCR4 co-receptors hinder conversion of HIV to AIDS Effective drug treatment (using a combination of drugs)
Pathophysiology and Etiology
When HIV enters the body, it gradually impairs the ability of the infected T4 cells to recognize foreign antigens and stimulate B-cell lymphocytes. The rate of progression from HIV infection to AIDS is related to the concentration of virus in the blood, the subtype and strain of infecting HIV, and the status of co-receptors on the CD4 cells.
salvage therapy
a treatment option for infected people with significant HIV drug resistance in whom possibilities for effective antiretroviral drug management are limited.
if a needle stick occurs
antiretroviral medications can reduce the risk of HIV infection if initiated within 72 hours after a possible exposure. Prophylaxis requires self-administration of medications once or twice daily for 28 days. nurses will not engage in any activity that there is a chance blood to blood transmission is possible with a patient
oppurtunistic infections
are infections that usually do not occur in individuals with healthy immune systems.
Distal sensory polyneuropathy (DSP) s/s
burning and numbness in the feet and later the hands. Because neuropathy is a side effect of several antiretroviral drugs, it is difficult to determine if the cause is actually destruction of the sensory peripheral nerves or drug therapy. To preserve and promote nerve function, vitamin B12 and thiamine supplementation is recommended.
NRTIs
by binding to viral DNA, NRTIs abort the terminal completion of gene copying.
CMV (cytomegalovirus)
can infect the choroid and retinal layers of the eye, leading to blindess. It can also cause ulcers in esophagus, colitis and diarrhea, pneumonia, and encephalitis.
Immunosuppression tends to facilitate the development of
cancer and speeds up the progression
When drug therapy is begun
clients are generally started on a combination of three antiretroviral drugs: Two reverse transcriptase inhibitors, drugs that interfere with the virus's ability to make a general blueprint One protease inhibitor, a drug that inhibits the ability of virus particles to leave the host cell.
Reverse transcriptase
copies viral RNA to viral DNA
Viremia
develop acute retroviral syndrome (viremia), also called acute HIV syndrome, which often is mistaken for flu or some other common illness.
2003, a new category of AIDS drugs called
entry inhibitors, which interfere with the ability of the virus to fuse with and enter the CD4 cell More recently, integrase inhibitors, a class of drugs that prevent the incorporation of viral DNA into the host cell's DNA
s/s
fever, swollen and tender lymph nodes, pharyngitis, rash about the face, trunk, palms, and soles; muscle and joint pain; headache; NVD; enlargement of the liver and spleen, weight loss, and neurologic symptoms such as visual changes or cognitive and motor involvement. However, admission of risk behaviors for HIV narrows the differential diagnosis. Although viral replication is rapid at this time, antibody tests cannot detect the infection.
AIDS dementia complex (ADC) s/s
forgetfulness, limited attention span, decreased ability to concentrate, and delusional thinking. Moods range from irritability to euphoria. Possible motor dysfunction is manifested by staggering gain and muscle incoordination, slowing of all movements, or paraplegia, which may be accompanied by incontinence
Protease
freeing the replicated viral particles into the cytoplasm of the cell
Occurence
homosexual men, IV drug users, heterosexual women, healthcare workers
What causes AIDS
human immunodeficiency virus (HIV) •People can remain well, sometimes up to 10 years or longer, despite being infected with HIV, before the initial infection develops into AIDS. During the asymptomatic period, the infected person can infect others
A T4-cell count of less than 500/mm3 indicates
immune suppression
protease inhibitor
indinavir (Crixivan), saquinavir (Invirase) interfere with the maturation of the viral copies
It is speculated that HIV
is an altered genetic form of simian (monkey) immunodeficiency virus (SIV). It is believed that the transformation allowed the virus to "jump" from chimpanzees to humans in Africa when humans slaughtered and consumed the meat of the chimpanzees.
Only one drug should never be prescribed
more effective to have multiple. Some clients take as many as all types. Combination medications are multiple medicines in one pill. Truvada is preexposure prohylaxis (PrEP) or prevention pill. It lowers an HIV negative person risk of acquiring the virus by 90%. For example, monogamous couple where one has HIV and the other does not.
what is the difference between nucleotide analogues and NRTIs /NNRTIs
nucleotides activate immediately when they enter the CD4 cell. They become incorporated within the viral DNA and cause premature termination of viral DNA synthesis.
•Adjunct Drug Therapy
other drugs used with antiretroviral drug therapy to help halt the progression of AIDS Hydroxyurea (Hydrea) — typically used to treat cancer - when combined with antiretroviral drugs it interferes with viral replication, increasing anti-HIV effect Cytokines—interferons (Roferon-A); increase blood levels of antiretroviral drugs; interleukin-2 (IL-2); stimulates the production of lymphocytes (boosts the body's immune defense against HIV)
early treatment promotes
restores normal CD4/CD8 cell counts improves immune function reduces viremia, the presence of viruses in the blood delays disease progression improves overall quality of life diminishes drug resistance lessens AIDS-defining illnesses and serious non-AIDS conditions decreases transmission of HIV to sex partners and prevalence in a community reduces perinatal transmission prolongs life
Category A, B, or C is based on
symptoms
category 2
t4 cell count 200-499
category 1
t4 cell count greater than 500
category 3
t4 cell count less than 200
The biggest disadvantage of enfuvirtide is
the medication requires self-injection twice daily, and nearly all users experience some type of reaction at the injection site.
what 3 tests confirm HIV
western blot test Indirect fluorescent antibody (IFA) test is used when the Western Blot test is not definitively positive. It mixes cells that are likely infected with HIV with immunoglobins and viewed using a fluorescent microscope Polymerase chain reaction (PCR) test, also called an RNA test, is used to detect the HIV virus itself. The PCR test is quite expensive and generally reserved for diagnosing infants with HIV born to mothers with HIV
HIV/AIDS is a pandemic
•34 million infected per World Health Organization •In the early history of HIV/AIDS, HIV occurred more often among homosexual men and IV drug users, but that exclusivity is no longer the case. Increasing number of heterosexual women are being infected, which in turn, leads to transmission of HIV to newborns. •In 2010, globally 1.8 million people died from AIDS. This is a decline from previous years. •The rate of HIV infection is 6.5 times higher in African Americans than in whites.
Western blot test
•A positive result on the Western blot confirms diagnosis; however, false-positive and false-negative results on both test are possible. It determines antibodies to specific HIV antigens such as p24, gp41, and gp120. A reaction to at least two antigens indicates a positive result. •Written consent must be obtained before an ELISA or Western blot test is performed. •The results of the tests require strict confidentiality.
AIDS-related complications
•AIDS dementia complex (ADC): degeneration of brain; affects mood, cognition, and motor functions Treatment: memantine (Namenda •Distal sensory polyneuropathy (DSP): abnormal sensations—burning and numbness -Treatment: tricyclic antidepressants—amitriptyline (Elavil), anticonvulsants—gabapentin (Neurontin)
Prevention strategies
•Abstain from sexual intercourse. •Avoid casual sex with multiple partners. •Use a condom or spermicide; nonoxynol-9. •Abstain from using IV drugs that contribute to disinhibition and hypersexuality. •Bank autologous blood (self-donated) or directed donor blood. •Nursing practice—standard precautions; report needlestick or sharp injury directed donor blood = specific blood donors among relatives and friends.
Transmission
•Body fluids: -Blood -Semen -Vaginal secretions -Breast milk HIV is not found in urine, stool, vomit, or sweat
Explain the concept of antiretroviral drug resistance and cross-resistance and techniques for reducing its potential
•Drug resistance occurs when strains of HIV develop mechanisms that promote their survival. •When drug resistance develops, it can also affect the response to similar prescribed drugs. •Drug resistance limits the ability to contain HIV and makes a person more susceptible to opportunistic infections. •The best advice for people who must take antiretrovirals is to take them exactly as prescribed, never omit or delay any doses or stop taking any of the drugs in the prescribed regimen without consulting the physician, and keep appointments for blood tests.
•Medical Management -Drug therapy goals
•Keep CD4 cell count above 350/mm3, undetectable viral load level
Reverse transcriptase inhibitor
•NRTIs - zidovudine (AZT) •NNRTIs - nevirapine (Viramune)
Reducing occupational risks
•Standard precautions •Safe handling of needles and sharp instruments •Transport specimens of body fluids in leak-proof containers •Clean and disinfect utility gloves •Remove barrier garments Recommendations by OSHA: Transport specimens of body fluids in leak-proof containers Clean and disinfect utility gloves Remove barrier garments (face shields, glasses) as soon as possible after leaving the client's room.
client teaching
•Understanding antiviral drugs do not cure AIDS but may slow its progression •Follow the medication schedule religiously; do not omit or increase the dose without physician approval •Comply with the timing of antiviral medications around meals •Eat small, frequent, well-balanced meals; try to maintain or gain weight •Drink plenty of fluids •Check weight weekly. Report progressive weight loss or loss of appetite to the physician •Avoid exposure to people with infections; avoid crowds •Notify the physician if signs of infection appear •Wear gloves and a mask when disposing of animal excreta, such as kitty litter •Wash all foods before cooking •Wash bedding with hot water separate from other laundry •Avoid smoking •Bathe daily, wash hands often - personal cleanliness is a must •Avoid dry dusty areas, excessive humidity, and extreme heat or cold. •Frequent rest periods, space activities to prevent fatigue •Do not share IV needles or donate blood •Inform healthcare professionals of HIV-positive status
People with HIV and AIDS are treated with
•antiretroviral drugs, adjunct drug therapy to boost the immune response, and supportive care during opportunistic infections.
Drug cross-resistance
•diminished drug response to similar HIV drugs
Integrase
•incorporates viral DNA into host cell's DNA
drug resistance
•ineffective response to a prescribed drug because of the survival and replication of exceptionally virulent mutations and noncompliance with drug therapy regimens.
When to start treatment
•is debatable. Some physicians recommend waiting to start to decrease the chance of drug resistance. Current guidelines based on research trials is to initiate treatment if the client has CD4 T-cell count less than 350 cells/mm3. Others believe start between 350 - 500 cells/mm3. Always start with co-founding factors like pregnancy, HIV-associated renal disease or hepatitis B. •Regardless of when antiretroviral therapy begins, it is critical that the clients with HIV comply with regular appointments for laboratory blood tests. •Physicians determines when to begin therapy based on client's CD4 T cell and viral load counts, potential compliance, medication side effects, and drug interactions.
A total T-cell count, T4 and T8 counts, and T4/T8 ratio determine
•the status of T lymphocytes. •It is now possible to measure a person's viral load, the number of viral particles in the blood.
The p24 antigen test and polymerase chain reaction test measure
•viral loads. They are used to guide drug therapy and follow the progression of the disease. •Viral load tests and T4-cell counts may be performed every 2 to 3 months once it is determined that a person is HIV positive. •Other labs and diagnostics are r/t opportunistic infections and cancers
a T4-cell count of 200/mm3 or less is an indicator of
AIDS
What classification would be assigned to an HIV-positive person with a T4 cell count of 350/mm3 who develops pneumocysitis pnumonia?
2C
Like all viruses, HIV is genetically incomplete.
A double layer of lipid material surrounds the incomplete HIV, referred to as a capsid. Surface-binding proteins, called gp120, project in all directions from the lipid bilayer. Another binding protein, called gp41, which resembles a stalk, attaches the gp120 to the capsid. Inside the capsid are three important enzymes—reverse transcriptase, integrase, protease and strands of RNA. When HIV encounters a helper T-cell lymphocyte, the binding protein gp120 fuses with the T cell's receptor, called a CD4 receptor. The fusion provides a means by which the capsid can insert its contents into the helper T cell. The discovery of co-receptors has led to the development of a new category or antiretroviral drugs called entry inhibitors.
ethical issues
Financial and insurance implications: fear of disclosure of HIV status will affect employment, health insurance coverage, housing Viatical settlements: name a person as beneficiary to life insurance in exchange for immediate cash Attorney or licensed insurance broker
Pneumonia caused by the organism
Pneumocysitis jiroveci. Rare among people with a healthy, intact immune system. Can become so severe it causes respiratory failure. Mechanical ventilation may be necessary to sustain adequate pulmonary function. Aerosol therapy and deep suctioning often are necessary to clear the lungs of thick sputum.
