AIDS (Acquired Immunodeficiency Syndrome) Transmission of HIV Clinical features and Course of HIV infection

AIDS is an advanced stage of HIV infection with symp­toms and opportunistic infections, with the CD4 cell count below 200 cells / IJL. Most AIDS patients are typical progressors and have a median survival time of 10 years. Some AIDS pa­tients may have no symptoms for up to 7 years.

 

AIDS (Acquired Immunodeficiency Syndrome)

AIDS (Acquired Immunodeficiency Syndrome)

• It was first reported in 1981 in US and is now a world­wide epidemic. It is caused by human immunodefi­ciency virus (HIV).
• The HIV attacks the immune system of the body lead­ing to a multitude of serious infections and cancers.
• An HIV positive individual is a patient who is in­fected with HIV but is asymptomatic.
• AIDS is an advanced stage of HIV infection with symp­toms and opportunistic infections, with the CD4 cell count below 200 cells / IJL.
• Most AIDS patients are typical progressors and have a median survival time of 10 years. Some AIDS pa­tients may have no symptoms for up to 7 years.
• Antiretroviral therapy has reduced the morbidity and mortality of HIV infection.

human immunodefi­ciency virus (HIV)

 

Persons at increased risk of HIV infection

Persons at increased risk of HIV infection

• · Injection drug users
• · Recipients of blood products
• · People with multiple sex partners
• · Patients of sexually transmitted diseases
• · Commercial sex workers and their partners
• · Gay men – People who have sex with persons of same sex
• · Sexual partners of persons with AIDS
• · Travelers, who visit areas of increased preva­lence and are indiscrete
• · Health care workers.

Transmission of HIV

Transmission of HIV infection

• 1. Sexual contact.
• 2. Transfusion of infected blood and blood products.
• 3. Mother to child – HIV is transmitted from infected mother to child during pregnancy, during deliv­ery, or after birth through breast- feeding.
• 4. Contact with infected instruments and body flu­ids – needle-sharing among drug users, acupunc­ture, tattooing, occupational exposure, medical procedures, contact with body fluids.
• Insects which feed on human blood cannot spread HIV.

Body fluids which transmit HIV infection

• · Semen
• · Vaginal secretions
• · Cerebrospinal fluid
• · Pleural fluid
• · Peritoneal fluid
• · Pericardial fluid
• · Amniotic fluid.

Clinical features and Course of HIV infectionPrimary HIV

Clinical features and Course of HIV infection Primary HIV

• There are non-specific, flu-like symptoms.
• Fever
• Lethargy
• Sore throat
• Malaise
• Rash Lymphadenopathy Arthralgias
• Myalgias Headache-Men i ng itis.
• Symptoms occur within 2 to 6 weeks after virus en­ters the body. Symptoms usually resolve in 2 to 3 weeks.

Clinical features and Course of HIV infectionPrimary HIV

From 2 to 6 weeks the person is very infectious and the virus is present in large quantities in genital flu­ids.

• Severe symptoms occur after 10 years or more in adults.
• The virus multiplies and kills the cells of the immune system especially CD4 T lymphocytes resulting in a decreasing number of CD4 cells.
• There is immunodeficiency and increased suscepti­bility to opportunistic infections and cancers.
• HIV infects the CNS, testes and other organs.

The virus remains latent in CD4 cells, hence it is not possible to eradicate HIV.

As immune function deteriorates, death becomes cer­tain.

HIV virus remains latent in CD4 cell

Opportunistic infections in HIV

• · Tuberculosis
• · Oropharyngeal candidiasis
• · Diarrhoea due to :
• Salmonella Shigella – Campylobacter
• – Clostridium difficile
• – Giardia
• – Amoeba
• – Isospora belli
• · Strongyloides
• · Cytomegalovirus
• – Herpes simplex j Varicella zoster virus
• – Bacterial pneumonia
• – Cryptococcal meningitis
• – Toxoplasmosis
• – Pneumonia due to Pneumocystis carinii
• – Mycobacterium avium complex infections
• – Cytomegalovirus retinitis
• – Kaposi’s sarcoma
• – Non-Hodgkin’s lymphoma

Opportunistic infections in HIV

hiv Investigations

Investigations HIV infection

• · ELISA +ve test is found within 3 months of getting the infection.
• · HIV infection is diagnosed on the basis of 3 ELISA tests.
• · AIDS is diagnosed on the basis of 2 ELISA rapid tests using different antigens.
• · Western Blot is used for confirmation of indeter­minate ELISA results.
• · Polymerase chain reaction (PCR) assays – Pres­ence of HIV DNA is diagnostic.
• · Rapid oral HIV test.

Indications for HIV screening

Indications for HIV screening

• · All individuals at high risk
• · Pregnant women
• · Donors of blood, semen, organs
• · All hospitalized patients where HIV prevalence
• rate is more than 1 per 1000
• · Patients of STD (sexually transmitted diseases)
• · Recurrent genital infections
• · Generalized lymphadenopathy
• · Recurrent herpes simplex or zoster
• · Tuberculosis
• · Unexplained weight loss or fever
• · Chronic diarrhea and Encephalopathy
• · Opportunistic infections.

Treatment HIV infection

• Antiretrovirals – these inhibit the viral replica­tion
• Treatment of opportunistic infections Psychosocial support. Antiretroviral therapy:
• Antiretroviral therapy should be started when CD4 count goes below 350 to 200 cells jlJL or HIV RNA is above 55,000 copiesjml.
• If CD4 counts are not available, total lympho­cyte count may be used.
• All symptomatic patients must be given antiretroviral therapy.
• Antiretroviral therapy must be continued indefi­nitely, with regular monitoring.

Highly active antiretroviral therapy (HAART) :

• HAART is a triple or 4 drug antiretroviral regime to suppress HIV replication for a long time.
• This leads to increased CD4 count and reduction in HIV RNA.

HIV IN WOMEN

HIV IN WOMEN

• Maternal HIV transmission can occur to the fetus dur­ing labour and delivery or after birth via breast feed­ing.
• HIV transmission is common during late pregnancy, labour and delivery.
• Maternal transmission of HIV occurs if there is low CD4 count, first-born twins, high viral loads.

OCCUPATIONAL EXPOSURE

• Nurses, lab technicians, doctors, residents, paramedicals, medical students are at increased risk.
• Pricks on the skin can result in AIDS more than mu­cous membrane exposure.
• Direct contact with blood and body fluids during sur­gery or diagnostic procedures must be avoided.

POST EXPOSURE PROPHYLAXIS

• PEP means treatment of a person after exposure, with antiretroviral therapy.
• PEP should be started within 1-2 hours of exposure
• to prevent HIV infection. –
• – It should be started as early as possible after expo­sure.
• PEP consists of 28 days of :
• IZidovudine 300 mg BD + Lamivudine 150 mg BD OR
• tavudine 30 mg BD + Lamivudine 150 mg BD
• An expanded regimen consists of Indinavir 800 mg 8 hrly added to the above regime.

HIV AND TUBERCULOSIS

HIV AND TUBERCULOSIS

• AIDS patients are very prone to tuberculosis espe­cially MDR TB – Multidrug resistant tuberculosis. There is drug interaction between antiretrovirals and Rifampicin, hence special regimens have been de­vised.

Other infections

• Infections with Salmonella, Shigella, Campylobacter and even atypical and low virulence pathogens are very common in AIDS patients.

Other measures for longer life in HIV patients

• · Regular health checkup and monitoring
• · Avoid uncooked food
• · Use filtered water only
• · Well-balanced diet
• · Regular exercises
• · Personal hygiene
• · Avoid pets
• · Quit smoking, alcohol, drugs
• · Avoid stress
• · Plenty of sleep and rest.