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HIV/AIDS

Viral Particle features

Outer envelope with special docking proteinso gp41 and gp120

assists in finding a host

inside the virus has protein coatings and enzymes

reverse transcription (RT)integraseo HIV particle gets inside a host cell and the CD+4 helper T-cell is

hijacked (this cell directs immune system defenses and regulates

the activities of all immune system cells)

More virus particles are created

Virus-Host Interactions

gp120 and gp41 proteins recognize receptors on the CD4+ T-cells

The gp120 first binds to the primary CD4 receptor, which changesits shape and allows for the gp41 to bind to one of the co-

receptors, this allow the virus to then enter the CD+4 T-cell

Retrovirus replicates cells DNAo HIV protease

Effects of HIV infection

CD4+ T-cells new job is to be an HIV factoryThe most important cell is removed from circulationo Over time the number of HIV particles overwhelms the immune

system

o The number of CD4+ Tcells decreases and the viral load (viral

numbers) increases

HIV leads to these immune system abnormalities:o Lymphocytopenia

o Increased production fo incomplete and nonfunctional

antibodies

o Abnormally functioning macrophages

As the CD4+ T-cells number drops the patient is at risk forbacterial, fungal, and viral infections, as well as some

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opportunistic cancers

10 billion new HIV particles can per produced per dayAIDS=HIV / HIV does not = AIDS

Diagnosis of AIDS = CD4+ T-cell count of < 200 cells/mm3Opportunistic infectionAIDS diagnosis remains and the patient never reverts to being just

HIV positive

HIV Classification

Clinical Category A:o HIV positive

o May be asymptomatic

o Person may have persistently enlarged lymph nodes

(lymphadenopathy)

Clinical Category B:o HIV infection plus

Deficiency in cell-mediated immunity

Disease complicated by HIV infection

Clinical Category C:o HIV + opportunistic disease= AIDS

On top of one of the three categories the patient also has aclassification based on the CD4+ T-cell count

o A,B,C either 1,2,3

o 1: when the count is at least 500/mL3

o 2: when the count is between 200 and 499 mL3

o 3: when the count is less than 200mL3

HIV Progression

From infection to AIDSo Can take form months to years

LTNP-long-term non-progressors

1% of the population10 or more years of infection with normal CD4+ Tcells countDefective co-receptors called delta32o Dependent upon

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How acquired- HIV acquired thru blood transfusion, AIDS

progresses quickly

Personal factors-frequency of re-exposure, presence of other

STDs, nutritional status, stress

Interventions

Incidence/Prevalence

Almost 1 million HIV/AIDS cases diagnosed with over 550kdeaths

1.1 to 1.8 million estimated infected with HIV21-44 year olds hardest hitOlder population is susceptibleo Sex/drug history

o Age-related immune system decline

o Decrease of estrogen in women thins the vaginal tissue and

increases susceptibility to any STD

26% new cases are womeno Poorer outcome with shorter survival than men

72% of new infections are in the racial and ethnic minorties in theUS

o Fear/lack of faith in health care system

o Poverty/limited access to drugs

Health Promotion/ Maintenance

Education

HIV is preventableo Teach modes of transmission

Sexual transmissiono ABCs of safer sex

o Virus concentrates in blood and seminal fluid

Gendero More easily transmitted to mucous membranes or nonintact

skin

o More easily transmitted from infected male to uninfected female

Sexual Actso Anal intercourse is the riskiest route

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Viral Loado Higher the load, greater the risk of infection

Other Modes of Transmission

Parenteral Transmissiono Sharing of needles, syringes, and other drug paraphernalia

Clean with water and bleach

Needle exchange program

o Donated blood screening

Perinatal Transmissiono Risk of 25% in women not using drug therapy

o 8% risk in women using drug therapy

Transmission and Health Care Workers

Needle stick or sharpes injuries are the main means ofoccupation-related HIV infection for health care workers

Best prevention for health care workers is the consistent use ofStandard Precautions is recommended by CDC and required

by joint commission

Testing

All sexually active people should know their HIV statuso Pre/posttest counseling

Assessment

Historyo Age

o Gender

o Occupation

o Living situation

o Blood transfusions between 1978-85

o Sexual practices/STDs

Opportunistic Infectionso Protozoal infections

PCP- most common opportunistic infections in HIV patients

Toxoplasmosis encephalitis- acquired through contact with

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contaminated cat feces or by ingesting infected, undercooked meat

Crytosporidiosis- manifestations range from a mild diarrhea to a

severe wasting with electrolyte imbalance

o Fungal Infections

Candida albicans- part of the natural flora of the intestinal tract,

occurs because the weakened immune system can no longer control

fungal growth

Cryptococcosis- debilitating memingitis and is sometimes a

widely spread infection in AIDS patients

Histoplamosis- begins as a respiratory infection and progresses

to a wide spread infection in the AIDS patient

o Bacterial Infections

Mycobacterium avium complex (MAC)- most common bacterial

infection in AIDS patients, infects the respiratory or GI tract, is a

systemic infection

Tuberculosis- anergy- inability to mount an immune response to

the antigen when having a TB test done

o Viral infections

Cytomegalovirus- can infect many sites in a person with AIDS

including the eye, respiratory and GI tracts, and the CNS

Herpes simplex virus (HSV)- manifestations are more widespread

and of longer duration among AIDS patients

Varicella-zoster virus (VZV)- usually not a new infection for

people with AIDS

Malignancies

Kaposis sarcoma- most common AIDS-related malignancyo Small, purplish brown, raised lesions that are usually not painful

or itchy

o Diagnosed by a biopsy and histologic examination of the lesion

Hodgkins/non-Hodgkins lymphomaInvasive cervical cancerEndocrine Changes

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Gonadal dysfunctiono Men have low testosterone levels

o Women often have irregular menstrual cycles

o Both have decrease in body muscle mass and a change in libido

Adrenal dysfunctiono Adrenal insufficiency resulting in

o Fatigue

o Weight loss

o Nausea

o Vomiting

o Low BP

o Electrolyte disturbances

Pancreatic changesOther Affected Systems

AIDS dementia complex (ADC)o 70% of people with AIDS

o Result of infection of the CNS by HIV

o Causes cognitive, motor, and behavioral impairments

AIDS wasting syndromeo May be a result of altered metabolism from cancer or infection

o Persistent and sometimes extreme weight loss, the patient may

appear quite emaciated

Skin changeso Dry, itchy, irritated skin and many types of rashes

Laboratory Assessment

Leukocyte countso Patients are usually leukopenic, with a WBC count of less than

3500 cells/mm3 and lymphopenic

Antibody tests- measure the patients response to the viruso Antibodies usually made in 3 wweks-3months

o ELISA or Western blot analysis

o Viral Load testing

Quantitative RNA assays

Monitor therapy effectiveness

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Other lab testso Blood chemistries

o CBC with diff

o LFTs

Testing stoolChest xraysPlanning/Implementation

Risk for infection

o Drug cocktail

HAART- Highly active antiretroviral therapy. Important to ensure

that these drugs are not missed, delayed, or administered in lower

than prescribed doses it he inpatient setting.

Nucleoside Analog Reverse Transcription Inhibitors (NARTIs)-have similar structure to the four nucleoside bases of DNA,

they compete with the actual nucleotide for placement in the

DNA. Thus they suppress production of reverse transcriptase

and inhibit viral DNA synthesis and replication

EX.

Combivir

Stavudine

Zidovudine

Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs)- inhibitsynthesis of reverse transcriptase, suppress viral replication

obut do not kill the virus

EX.

Etravirine

Nevirapine

Protease Inhibitors- block HIV protease enzyme, preventing viralreplication and relrease of viral particles. Make the protrease

enzzyume work on the drug rather than ton the initial large

protein

EX.

Fosamprenavir

Darunavir

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Kaletra

Fusion Inhibitors- block the fusion of HIV with a host cell byblocking the ability of gp41 to fuse with the host cell.

Infection of new cells does not occur

Entry Inhibitors- prevent infection by blocking the CCR5 receptoron CD4+ Tcells, prevent cellular infection with HIV

Integrase Inhibitors- prevent infection by inhibiting the enzymeintegrase, viral proteins are not made and viral replication in

inhibited

Community-Based Care

Home care managemento Assess status and ability to perform ADLs

o Assess available resources

o Help family make arrangements for careif needed

Health Teachingo Modes of transmission and prevention

o Infection control measures

o Diet teaching

o Social strategies

Psychosocial Prepo Support and strategies for social stigma and rejection

Health Care Resourceso Community outreach

o Respite care

o Referral services

o Mental health/behavioral health

o Support groups

Evaluation/Outcomes

Adherence to prescribed drug therapy regimenSafe sex practicesRemain free from OIsAdequate respiratory functionAcceptable level of comfortAdequate weight

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Maintain skin integrityRemain orientedMaintain self-esteemMaintain support system