HSC4711 Test III Study Guide Chapter 13 HIV Infection and AIDS Human immunodeficiency virus HIV is the virus which causes AIDS acquired immunodeficiency syndrome Without treatment AIDS kills nearly all of its victims Approximately 65 million people around the world have been infected with HIV since the epidemic began o Nearly 1 of the world s population o About 30 million are affected o 21 of HIV infected Americans are unaware of their condition What is HIV Infection Chronic disease that progressively damages the body s immune system making an otherwise healthy person less able to resist a variety of infections and disorders o HIV attacks and invades T cells CD4 monocytes macrophages and other essential elements of the immune system o HIV enters a human cell and converts its own genes into human cells o Inserts this DNA into chromosomes of host cell o The viral DNA takes over the CD4 cell and replicates destroys the immune functions of CD4 cell People with AIDS are vulnerable to a number of opportunistic secondary infections an infection caused when organisms take the opportunity presented by a primary initial infection to multiply and cause a new different infection The asymptomatic period showing no signs or symptoms of a disease also called the latency phase may last from 2 to 20 years o During this time the virus progressively infects and destroys the cells of the immune system People infected with HIV can transmit the disease to others even if they are symptom free Transmitting the Virus HIV lives only within cells and body fluids not outside the body HIV is transmitted by blood and blood products semen vaginal and cervical secretions and breast milk Three primary means of transmission o From specific kinds of sexual contact o From direct exposure to infected blood o From an HIV infected woman to her fetus during pregnancy or child birth or to her infant during breastfeeding Populations of Special Concern for HIV Infection Most common means of exposure o Sexual activity between men o Drug injection o Heterosexual contact African American women and Latinos make up an increasingly large proportion African American men and women are vastly overrepresented among people of all U S AIDS cases newly diagnosed with AIDS HIV in the United States is increasingly becoming a disease that effects minorities women and the poor Symptoms of HIV Infection Within a few days or weeks on average 2 to 4 weeks after exposure to the virus most people will develop symptoms o Persistent swollen lymph nodes lumps rashes sores or other growths on or under the skin or on the mucous membranes of the eyes mouth anus or nasal passages persistent yeast infections unexplained weight loss fever and drenching night sweats dry cough and shortness of breath persistent diarrhea easy bruising and unexplained bleeding profound fatigue memory loss difficulty with balance tremors or seizures changes in vision hearing taste or smell difficulty swallowing changes in mood and other psychological symptoms and persistent or recurrent pain Pneumocystitis carinii pneumonia is the most common infection seen in people with HIV Kaposi sarcoma a rare form of cancer is commonly seen among infected men Symptoms take months or years to develop but as immune system weakens variety of symptoms develop o Difficult to treat yeast infections in women o Tuberculosis Diagnosing HIV Infection Most common tests check for the presence of antibodies to the virus o HIV antibody tests used for screening accurate and inexpensive o ELISA standard test a blood test that detects the presence of antibodies to HIV if it is positive a second test is done o Western blot or immunoflourescence assay is done to confirm results More accurate and expensive test used to confirm positive results from an ELISA test If HIV positive the next step is to determine the disease s severity to plan appropriate treatment o The immune systems status can be gauged by measuring CD4 T cells every few months more advance number will drop Treatment Antiviral drugs in current use to combat HIV fall into several categories based on how they block HIV replication o Reverse transcriptase inhibitors including AZT zidovudine inhibits enzyme which HIV uses to integrate its genetic material into human cells o Protease inhibitors target the enzyme HIV uses to create a protein coat for each new copy of itself o Entry inhibitors block HIV from entering and infecting cells o HAART can reduce HIV in the blood to undetectable levels o Post exposure Prophylaxis PEP involves 28 days of HAART which should begin within 72 of exposure Chlamydia Most common bacterial STD in the U S Can cause sterility in men and women o In women it can lead to pelvic inflammatory disease infertility and ectopic pregnancy o In men chlamydia is the most common cause of epididymitis inflammation of sperm carrying ducts and causes half of all cases of urethritis inflammation of the urethra Symptoms Women most are asymptomatic some notice increased vaginal discharge burning with urination pain or bleeding with intercourse and lower abdominal pain Men painful urination a slightly watery discharge from penis pain in testicles or lower abdomen Symptoms in both men and women can begin within 5 days of infection However most people experience few or no symptoms increasing the likelihood that they will inadvertently spread the infection to their partners Diagnosis and treatment Laboratory tests on a simple urine sample or a small amount of fluid from the urethra or cervix Once diagnosed infected person and partner are given antibiotics Gonorrhea Can cause PID in women and epididymitis urethritis in men It can also cause arthritis rashes eye infections A woman who is infected during pregnancy is at risk for preterm delivery and for having a baby with life threatening gonorrheal infection of blood or joints An infant passing through the birth canal of an infected mother may contract gonococcal conjunctivitis an infection in the eyes that can cause blindness if not treated Being infected with gonorrhea increases the likelihood that HIV will be transmitted Symptoms o Can infect throat or rectum through oral or anal sex Men symptoms are due to urethritis which causes urinary discomfort and a thick yellow white discharge from the penis The lips of urethral opening might become inflamed and swollen In some cases the lymph glands in the groin become enlarged and swollen Half of men have minor or no symptoms Women usually