Human immuno deficiency virus-HIV microbiology

Hiv in detail

2. What is HIV?
•Human:Infecting human beings
•Immunodeficiency:Decrease or weakness in
the body’s ability to fight off infections and
illnesses
•Virus:A pathogen having the ability to
replicate only inside a living cell
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Structure of HIV
3
Envelope
Core p24
RNA
Reverse
Transcriptase
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4. What is AIDS?
Acquired: To come into possession of something
new
Immune Deficiency:Decrease or weakness in the
body’s ability to fight off infections and illnesses
Syndrome:A group of signs and symptoms that
occur together and characterize a particular
abnormality
4
AIDS is the final stage of the disease caused
by infection with a type of virus called HIV.
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HIV vs. AIDS
HIV is the virus that causes AIDS
Not everyone who is infected with HIV has
AIDS
Everyone with AIDS is infected with HIV
AIDS is result of the progression of HIV
Infection
Anyone infected with HIV, although healthy,
can still transmit the virus to another person
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6. HIV is a fragile virus
HIV can only be transmitted under specific
conditions that allow contact with infected
body fluids : blood ,semen, vaginal secretions,
and breast milk
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7. HIV infected individuals can transmit HIV to
others with in a few days after getting
infected , after that the ability to transmit
infection is life long
Transmission of HIV depends on the duration
and frequency of contact, volume of fluid,
virulence and concentration of the organism
and host immune status
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8. Large amount of HIV can be found in the
blood during the firs 6 month of infection and
again during the last stages of disease
HIV is not spread casually
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9. The virus cannot be transmitted through
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10. HIV is transmitted through
Sexual intercourse with
infected person
Contact with blood and
blood products
Perinatal transmission
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11. PATHOPHYSIOLOGY
Viruses are intracellular parasites
HIV belongs to a group of viruses known as
retroviruses
Retroviruses carry genetic material in the
form of ribonucleic acid (RNA) rather than
DNA
HIV consist of a viral core containing the viral
RNA ,surrounded by an envelope consisting
of protruding glycoprotein
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13. All viruses target specific cells
HIV target cells with CD4 receptors which are
expressed on the surface of T lymphocytes,
monocytes, dendritic cells and brain
microglia
Mature T cells are composed of two major
subpopulations that are defined by the cell
surface receptors of CD4 and CD8
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14. The HIV life cycle is complex and
consist of the following steps
UNCOATING
DNA SYNTHESIS
INTEGRATION
TRANSCRIPTION BUDDING
TRANSLATION CLEVAGE
ATTACHMENT
HOST CELL
DESTRUCTION
,NEWLY FORMED HIV
RELEASED IN THE
BLOOD CAN INFECT
OTHER CELLS
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15. ATTACHMENT
In this first step, the
GP120 and GP41
glycoprotein's of HIV
bind with the hosts
uninfected CD4+
receptors and
chemokine co-receptors
Which results in fusion of
HIV with the CD4+ T cell
membrane
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16. UNCOATING
Only the contents of
HIV’s viral core (two
single stranded viral
RNA and three viral
enzymes ::::reverse
transcriptors,
integrase, and
protease )are
emptied into the
CD4+Tcells
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17. DNA SYNTHESIS
HIV changes its
genetic material from
RNA to DNA through
the action of reverse
transcriptase
Resulting in double
stranded DNA that
carries instruction for
viral replication
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18. INTEGRATION
New viral DNA enters the nucleus of the
CD4+T cells
And through the action of the integrace id
blended with the DNA of the CD4+T cells
Which results in permanent life long
infection
Prior to this uninfected person is only
exposed to ,not infected with HIV.with this
step HIV infection is permanent
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20. TRANSCRIPTION
When the CD4+T
cells is activated the
double stranded DNA
forms single stranded
messenger RNA
(mRNA),which builds
new viruses
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21. TRANSLATION
The mRNA creates
chain of new proteins
and
enzymes(polyproteins)
that contain the
component needed in
the construction of new
virus
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22. CLEAVAGE
The HIV enzyme
protease cuts the
polyprotein chains
into the individual
proteins that make
up the new virus
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23. BUDDING
New proteins and viral RNA migrate to the
membrane of the infected CD4+T cells
Exit from the cells and start the process all
over
HIV replication and budding occurs which can
destroy the host cells .newly formed HIV
released into the blood can infect other
CD4+T cells
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25. 7/9/2024

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27. CLINICAL MANIFESTATION AND
COMPLICATIONS
ACUTE INFECTION
Development of HIV specific antibodies is
frequently accompanied by a flu like
syndrome of
fever,
swollen lymph glands
sore throat,
head ache
malaise
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29. nausea muscle and joint pain
diarrhea and diffuse rash
These symptoms called acute HIV infection
generally occur 1 to 3 weeks after the initial
infection and last for 1-2 weeks although
some symptoms may persist for more than
months
During this period high viral load is noted and
CD4Tcell count fall temporarily
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31. CHRONIC HIV INFECTION
EARLY CHRONIC INFECTION
The median interval between untreated HIV
infection and a diagnosis of AIDS is about 11
years
This phase is asymptomatic phase
Although fatigue, head ache, low grade fever,
night sweats, persistent generalized
lymphadenopathy can occur
During this period the patient may not be
aware of that they are infected
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32. INTERMEDIATE CHRONIC INFECTION
Symptoms become more worse at this point
Persistent fever
Frequent drenching night sweat
Chronic diarrhea
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33. 33
Recurrent head ache
Fatigue
Localized infection
lymphadenopathy
Nervous system manifestation
The most common infection occur
during this time is ; Candida,
varicella zoster virus
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34. LATE CHRONIC INFECTION
OR AIDS
HIV related immune
disorders
Development of
opportunistic infection
Variety of malignancies,
wasting and dementia
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38. 7/9/2024
SYSTEM VISE FEATURES
RESPIRATORY
Shortness of breath
Dyspnea
Cough
Chestpain
Pneumocystis
pneumonia
Tuberculosis
GASTROINTESTINAL
Loss of appetite
Nausea
Vomiting
Oral or esophageal
candidiasis
Chronic diarrhea
Profound weight loss
Fluid and electrolyte
imbalance
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39. 7/9/2024
ONCOLOGIC
Kaposi's sarcoma
Lymphoma
Invasive cervical
cancer
NEUROLOGIC
Cognitive changes
Disturbed motor,
visual,attention,
executive functions
Preripherla
neuropathy
HIV Encephalopathy
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40. DIAGNOSTIC STUDIES
Main problem in diagnosis is during the time
of window period
Laboratory assessment of CDt4+T cells count:
normal count is 800-1200cells/µl
Decreased WBC count
Low neutrophils
Low platelet count
Altered liver function test
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41. The CD4countnormal
range is
500to1500cell/mm^3. If a
patient is left untreated,
levels can drop below
200cells/mm^3, which is
one indication for the
diagnosis ofAIDS.

42. Highly sensitive enzyme immune assay : done
to detect serum antibodies that bind to HIV
antigen on test plates
WESTERN BLOT ASSAY is used to confirm
seropositivity when the EIA result is positive
Rapid test kit (Oraquick)
Viral load test measures plasma HIV RNA
levels
HIV culture or plasma culture is also used to
detect HIV virus
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43. TEST FINDINGS
EIA-( ENZYME
LINKED IMMUNO
SORBANT ASSAY)-
OR, ELIZA
Antibodies are detected, resulting in
positive results and marking the end of the
window period
Western blotDetect antibodies to HIV and used to
confirm EIA
Viral load Measures HIV RNA in plasma
CD4/ CD8 These are markers found on lymphocytes.
HIV kills CD4+ cells, which results in a
significantly impaired immune system,
Oraquick In home HIV test-oral swab test
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44. COLLABORATIVE CARE
Collaborative care focuses on
Monitoring HIV disease progression and
immune function
Initiating and monitoring ART
Preventing the development of opportunistic
infection
Decreasing the complication
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45. ANTIRETROVIRAL THERAPY
ART is the combination of several
antiretroviral medicines used to slow the rate
at which HIV makes copies of itself(multiples)
in the body.
A combination of 3 or more medicines is
more effective than using just one medicine
to treat HIV
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46. GOAL
Reduce HIV-associated morbidity and
prolong the duration and quality of survival
Restore and preserve immunologic functions
Maximally and durably suppress plasma HIV
viral load
Prevent HIV transmission
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47. Nucleoside
reverse
transcriptase
inhibitors
nucleotide
reverse
transcriptase
inhibitors
Nonnucleoside
reverse
transcriptase
inhibitors
Protease
inhibitor
Combination
entry
inhibitors/
fusion
inhibitors
Combination
therapy
Zidovudine
Didanosine
Stavudine
Lamivudine
Abacavir
Emtricitabine
Combivir
Trizivir
Tenofovir
Truvada
•Nevirapine
•Delavirdine
•Efavirenz
•Saquinavir
•Indinavir
•Ritonavir
•Nelfinavir
•Amprenavir
•Kaletra
•EnfuvirtideAtripla
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48. Nucleoside reverse transcriptase
inhibitors
NRTIs block
reverse
transcriptase thus
conversion of RNA
to DNA is stopped.
Thus it prevents
replication
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49. Nucleotide reverse transcriptase
inhibitors
It interfere with the
HIV life cycle in the
same way as NRTIs
Blocks reverse
transcription.
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50. Nonnucleoside reverse transcriptase
inhibitors
It bind to and block HIV reverse transcriptase.
Thus prevents conversion of RNA into DNA
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51. Protease inhibitors
HIV protease inhibitors are peptide-like
chemicals that competitively inhibit the
action of the virus aspartyl protease.
It prevents protreolytic cleavage of HIV Gag
and polyproteins that include essential
structural and enzymatic components of the
virus.
This prevents conversion of HIV particles into
their mature infectious form.
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52. Fusion inhibitors
It blocks the HIV
envelop from
merging with
the host CD4
cell
membrane(fusi
on).
This prevents
HIV from
entering the
CD4 cell.
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53. Integrase strand transfer inhibitors
Block integrase –
an HIV enzyme
HIV uses
integrase to
insert its viral
DNA into the
DNA of host CD4
cell.
Blocking this
prevents HIV
replication
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54. Other modalities
Treatment of opportunistic infection
Prevention of opportunistic infection
Antidiarrheal therapy
Chemotherapy
Antidepressant therapy
Nutritional therapy
Complementary and alternative modalities
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55. Treatment of opportunistic infections
Pneumocystis pneumonia-TMP-SMZ is the
treatment of choice
Can be given as out patient therapy and is
highly effective among patients with mild to
moderate PCP
Adjunctive corticosteroids should be started
within 72hrs
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Mycobacterium avium complex-Azithromycin
(zithromax) or Clarithromycin are given as
prophylactic agent.
Or Rifabutin can also be given
Cryptococcal meningitis –
IV Amphotericin B with or without oral
Flucytosine or Fluconazole
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57. Cytomegalovirus retinitis –
Oral valganciclovir
Iv ganciclovir
Iv foscarnet
Iv cidofovir
Other infections –
Oral acyclovir, famciclovir, valcyclovir and
ketoconazole
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58. Prevention of opportunistic infection
TMP-SMZ is an antibacterial agent used to
treat various infections
TMP-SMZ is
TMP-TRIMETHOPRIM,
SMZ-SULFAMETHOXAZOLE
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59. Antidiarrheal therapy
In HIV/AIDS it is not unusual for this to recur
and become a chronic problem.
Therapy with Octreotide acetate (sandostatin)
a synthetic analogue of somatostatin is
effective to manage chronic severe diarrhea
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60. Chemotherapy
Kaposi’s sarcoma: (KS) is a type of cancer that
can form masses in the skin, lymph nodes, or
other organs. The skin lesions are usually
purple in color. They can occur singularly, in a
limited area, or be widespread. It may worsen
either gradually or quickly.
radiation therapy is effective as a palliative
measure to relieve localized pain due to
tumors
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61. Interferons-an antiviral and
antitumor effects –
alpha-interferone have
shown tumor regression
and improvement in
immune system function

62. Lymphoma:
Combination chemotherapy and radiation
therapy regimens may produce an initial
response but it is usually short-lived
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63. Antidepressant therapy
Psychotherapy integrated with
pharmacotherapy is used.
Antidepressants like imipramine,
desipramine, and fluoxetine may be used.
A psycho stimulant-methylphenidate may be
used in low dose in patients with
neuropsychiatric impairment.
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64. Nutrition therapy
Nutrition therapy should be part of the
overall management plan and should be
tailored to meet the nutritional needs of the
patient, whether oral diet , enetral tube
feeding, or parenteral nutritional support.
The goal is to maintain ideal weight and when
necessary to increase weight.
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65. Appetite stimulant have been found
successful in increasing appetite.
Megestrol acetate, a synthetic oral
progestrone preparation is used, increase
body weight by restoring body fat.
Oral supplement may be used when the diet
is deficient in calories and proteins.
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66. Oral supplement should be free of lactose
and high in calories and easily digestible
protein, low in fat, palatable, inexpensive and
tolerated without causing diarrhea
Parenteral nutrition is the final option
because of its prohibitive cost and associated
risks, including possible infection.
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67. Complementary and alternative
modalities
Combined with traditional therapy, CAM may
improve the patient’s overall wellbeing.
Four categories:
Spiritual or psychological therapy
Nutritional therapy
Drug and biologic therapy
Treatment with physical forces and devices –
acupuncture, acupressure, massage therapy,
reflexology, therapeutic touch and yoga.
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68. Supportive care
Nutritional support
Manage skin breakdown
Pain management
Relaxation and guided imagery
Respiratory therapy
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69. COMPLICATIONS
Opportunistic infection
Respiratory failure
Wasting syndrome
Side effects of medication
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70. Nursing management
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71. Assessment
Nutritional status
Skin integrity
Respiratory status
Neurologic status
Fluid and electrolyte balance
Knowledge level
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72. Interventions
Promote skin integrity
Promote usual bowel pattern
Prevent infection
Improve activity tolerance
Maintain coherent thought processes
Improve airway clearance
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73. Relieve pain and discomfort
Improve nutritional status
Decreasing the sense of isolation
Coping with grief
Improving knowledge of HIV
Monitor and manage potential complications
Promote home and community based care
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74. 7/9/2024

75. Preventive education
Reproductive education
Standard precautions
Post exposure prophylaxis
Vaccination
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