ACQUIRED IMMUNODEFICIENCY SYNDROME

presented by :

Deepti Awasthi

CONTENTS• Introduction• History• Epidemiology• HIV Virus• Routes of

transmission• Pathogenesis

• Clinical signs and manifestations

• Oral manifestations

• Lab diagnosis• Prophylaxis• Treatment• Universal

precautions• References

INTRODUCTION

• Since, the initial recognition of AIDS in the US in 1981,tremendous advances have taken place in the understanding of this dreaded disease in the last decade as regards its epidemiology, etiology, immunology, pathogenesis, clinical features & morphologic changes in various tissue and organs of the body.

• .• 1st DEC - world AIDS day by the WHO.

EPIDEMIOLOGY

• Acc. To WHO, in nov 2003

40 million - infected worldwide

5 million – newly infected

3 million – died

2.2 million children - <15 yr • In india,

2nd largest after south africa

In 2003, 5 million infected

Status of HIV epidemic in India

High Prevalent states

Maharashtra

Manipur

Andhra

Pradesh

Nagaland Tamil

Nadu Karnataka

HISTORY

• In monkeys – for over 100,000 years• In 1956 – in central africa : “ gay fever ”• In 1981 – first indication came from new

york & los angeles• In 1983 – Luc Montagnier & colleagues

from pasteur institute ,paris , isolated a retrovirus – LAV

• In 1984 – Robert gallo & colleagues , USA : HTLV- III

• In 1985, serological tests available for anti-HIV antibodies.

• In 1986, international committee decided on the generic name - HIV

• In india –

1st case reported in chennai

HIV virus

• Lentivirus subgroup, family retroviridae.• 2 forms :

HIV-1 : US & central africa

HIV-2 : west africa & india

The genome – 3 str. Genes : gag, pol, env.

ROUTES OF TRANSMISSION

• 1. SEXUAL CONTACT

- 75% of all cases

- male to male & male to female is more potent route than female to male.

• 2. PARENTERAL

- 25%

1) I.V. Drug abusers

2) hemophiliacs

3) blood recipients

• 3. PERINATAL• Vertical transmission • Several risk factors:

- pre term delivery

- low maternal antenatal CD4 count

- illicit drugs during pregnancy.

- elective cesarean delivery – by 87% +

ZVT in the mother & infant.

• Besides blood ,HIV has been isolated from no. of body fluids & tissues :

semen, vaginal secretions , cervical secretions, breast milk, CSF, synovial, pleural, peritoneal, pericardial & amniotic fluid.

• Salivary protein – secretory leucocyte PI

anti –HIV activity

NO

SHAKING

HANDS

SHARING

HOUSE HOLD

FACILITIES

MOSQUITOES,

BUGS,INSECTSB

ITE

HUGGING

• STERILIZATION & DISINFECTION

• HEAT : Virus is very fragile & can be eliminated easily by hot water at 56% for 30 mins.

• CHEMICALS : NaOCl – 0.1%

Ethanol – 70%

Formaldehyde – 5%

Glutaraldehyde – 2%

H2O2 – 0.3%

PATHOGENESIS Interaction of gp120 of HIV to CD4+T cell

internalisation of virion

uncoating of virion

reverse transcriptase

proviral DNA

unintegrated, integrated

Activated CD4+T cell inactivated CD4+T cell

budding,syncytia LATENT PHASE

CYTOPATHIC PHASE

Quantitative depletion qualitative failure to respond

• HIV infection of nervous system :

• Out of non-lymphoid organ involvement, HIV inf of nervous system is the most serious.

• Some presenting features include :

acute aseptic meningitis

subacute encephalitis

vacuolar myelopathy

peripheral neuropathy

STAGES

1) ACUTE HIV INFECTION

• 3-6 wks – 50% persons experience low grade fever, malaise, headache, lymphadenopathy. Resolves within wks

• Tests for HIV antibodies are –ve at onset & becomes +ve during its course- “SEROCONVERSION ILLNESS” .

• P 24 antigen

2) ASYMPTOMATIC OR LATENT INFECTION

• All persons pass through this phase which may last upto several years.

• +ve HIV antibody tests • This period of clinical latency , does not

mean microbiological latency as virus replication goes on throughout.

• The CD4+T cell count decreases

< 200 = clinical AIDS sets in

3) PERSISTENT GENERALIZED

LYMPHADENOPATHY

4) AIDS RELATED COMPLEX (ARC)

• Includes various constitutional symptom : unexplained fever > 1mth weight loss > 10% chronic diarrhoea > 1mth• Oppurtunistic infections

• 5) AIDS

• End stage disease• Irreversible breakdown of immune

defence mechanism• Progressive oppurtunistic infection &

malignancies.

OPPURTUNISTIC INFECTIONS & MALIGNANCIES

• MALIGNANCIES:• Kaposi sarcoma• Lymphoma• BCC• Melanoma

• VIRAL

CMV HERPES SIMPLEX

• BACTERIAL

• TB• Salmonellosis• Campylobacter inf• Nocardia & actinomycetes• Legionellosis

• PARASITIC

• PNEUMOCYSTITIS

CARINII PNEUMONIA

• TOXOPLASMOSIS

• MYCOTIC

• Candidiasis• Cryptococcosis• Aspergillosis• Histoplasmosis

ORAL LESIONS in child

PAROTID SWELLINGS ORAL CANDIDIASIS

HAIRY LEUKOPLAKIA HERPETIC LESIONS

DELAYED TOOTH ERUPTION

ADVANCED HIV/AIDS DISEASE DEFINITIONS FOR

SURVEILLANCE FOR ADULTS

Any clinical stage 3 or stage 4 disease

or,

where CD4 is available, any clinical stage and CD4 <350/mm3

• Diff. b/w adult & pediatric AIDS:

• Children develop humoral immunodef. early, leading to recurrent bacterial inf.

• Failure to thrive, chronic diarrhoea ,lymphadenopathy, TB – common manifestation.

• Lymphocytic interstitial pneumonia- seen mostly in children.

Testing Options for HIV

LAB DIAGNOSIS OF AIDS

• A. IMMUNOLOGICALTESTS

• Leucopenia• Lymphopenia• Thrombocytopenia• CD4+T cell < 200 / mm3• T4 : T8 is reversed.• Lymph node biopsy

• B. SPECIFIC TESTS :

1. Antigen detection• The major core antigen , P24, earliest

virus marker to appear in blood.• IgM antibodies appear in 4-6 wks,

followed by IgG antibodies.

2. Virus isolation & culture• From peripheral lymphocytes• Viral replication can be detected by-

reverse transcriptase activity

3. POLYMERASE CHAIN REACTION• Most sensitive & specific test• Gold standard for diagnosis in all stages• 2 forms : DNA & RNA

4. ANTIBODY DETECTION• Simplest & most widely employed technique.• 2-8 wks to months for antibodies to appear• Highly infectious• Seronegative infective – “window period”• 2 types : screening & confirmatory tests

• Screening tests – high sensitivity

not highly specific

false + ve results

The most widely used screening test is ELISA.

• Confirmatory tests – WESTERN BLOT.

In this HIV proteins are seperated acc. to their electrophoretic mobility by poly- acramide gel electrophoresis are blotted onto strips of nitrocellulose paper.

PROPHYLAXIS• The prevention aims at –

Health education

Identification of sources

Elimination of high risk activities• No specific vaccine is available.• Several possible strategies have been

explored for vaccine production. These include immunisation with –

a) Modified whole virus

b) Subunits

c)Target cell protection by anti-CD4 antibody

Treatment Options

39

TREATMENT1. Treatment & prophylaxis of infections &

tumours

2. General management

3. Immunorestorative measures-

Administration of IL-2, thymic factors ,leucocyte transfusion & bone marrow transplantation.

4. Specific anti – HIV agents

NRTI • Zidovudine , stavudine , lamivudine

Didanosine , abacavir. NNRTI• Nevirapine, delavirdine PI• Saquinavir , ritonavir , indinavir FI• Enfuvirtide Integrase I• Raltegravir CCR5 antagonist• Maraviroc

PREVENTION• Safer sex methods• Screening of blood donors• Disposable syringes, needles etc• Infected women – advised against

pregnancy• For interruption of perinatal transmission

ZVT 200 mg TID to the women & continued during delivery

decreases rate to < 8 %.

IRIS• When a pt. starts ART, his immune

deficiencies improve. This sometimes results in uncontrolled inflammatory responses. Hence, pt. may show worsening of clinical features or lab parameters inspite of improving CD4 counts & decrease viral load.

• TREATMENT

- Symptomatic - NSAIDS

- severe: prednisolone - life threatening: stop ART

PEP

• ART should be started within the first few hours & no later than 72 hrs .

• HIV testing should be done initially & following 3 & 6 months.

• EXPOSURE

Less severe - 2 drug PEP

more severe - 3 drug PEP

• Biohazard to Dental workers :

• Larger quantity of blood loss• Repeated blood to blood contact• Longer• Length of surgical procedure• Needle prick injuries

UNIVERSAL PRECAUTIONS

• Alert all the time.• Single chair room• Gloves – examination• Dental units covered with water proof

sheets.• Impervious surgical gown, cap & mask. • For procedure – double gloves• Airotor use – avoided

• In suction bottle – 2% glutaraldehyde 30 ml

2% NaOCl 60 ml

• Needles discarded immediately

• Bag containing waste – incineration• Instruments – reautoclaved twice by double

sterilization

Spillage of blood & body fluids , area saturated with 1% NaOCl for 30 mins. Then mopped with an old linen towel.

References :• Ananthanarayan and paniker’s textbook of

microbiology ; 8th ed.• Kliegman, behrman, jenson,stanton. Nelson

textbook of pediatrics ; vol.1• Harsh mohan . Essential pathology ; 3rd ed• Mehta PJ. Practical medicine ;19th ed• Chandra S, chandra S. Textbook of

pedodontics. 2002• Davidson S. principles & practice of

medicine;19th ed.• www.google.com

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