03 07 2013 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 Nearly only 1 of the world s population About 33 million are infected 21 of HIV infected Americans are unaware of their condition Aids remains the primary cause of death in Africa What Is HIV Infection Chronic disease that progressively damages the body s immune system that progressively damages the body s immune system HIV attacks and invades CD4 T cells and other essential elements of the immune system HIV enters a human cell and converts It own genetic into the human cells Inserts this DNA into chromosomes of host cell The viral DNA takes over the CD4 cell and replicates destroys the immune functions of CD4 cell Unlike the virus the immune system cannot make new cells indefinitely The destruction of the immune system is signaled by the loss of CD4 T cells People with AIDS are vulnerable to a number of opportunistic secondary infections The first weeks after being infected with HIV are called the primary infection phase The asymptomatic period also called the latency phase may last from 2 20 years 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 translation and breast milk Three primary means of transmission From specific kinds of sexual contact Direct exposure to infected blood And from the HIV infected woman to her fetus during pregnancy or childbirth or to her infant during breastfeeding During Vaginal intercourse male to female transmission is more likely to occur than female to male transmission The presence of lesions blisters or inflammation from other STDs in the genital anal or oral areas makes it two to nine times easier for the virus to be passed Populations of Special Concern for HIV Infection Most common means of exposure Sexual activity between men Injection drug Heterosexual contact African American women and Latinos make up an increasingly large proportion of all U S AIDS cases African American men and women are vastly overrepresented among people newly diagnosed with AIDS Increasingly a disease that effects minorities women and the poor Symptoms of HIV Infection Within a few days or weeks on average 2 4 weeks after exposure to the virus Symptoms Flu like symptoms HIV RNA assay directly measures the amount of virus in the body Pneumocystis pneumonia a fungal infection is the most common infection seen in people with HIV Kaposi s 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 Difficult to treat yeast infections in women Tuberculosis Diagnosing HIV Infection Most common tests check for the presence of antibodies to the virus HIV antibody tests used only for screening They are accurate and relatively inexpensive ELISA standard test If this test comes back positive then a second test needs to be done either a Western blot or immunofluorescence assay to confirm the results If HIV positive the next step is to determine the disease s severity to plan appropriate treatment how by measuring CD4 T cells every few months Treatment no known cure for HIV but medications can significantly alter the course of the disease and extend life Antiviral drugs Reverse transcriptase inhibitors AZT zidovudine Inhibits the integration of HIV virus into human cells Protease inhibitors target the enzyme HIV uses to create a protein coat for each viral copy Entry inhibitors block HIV from entering and infecting cells HAART can reduce HIV in the blood to undetectable level Post exposure Prophylaxis PEP involves 28 days of HAART which should begin within 72 hours of exposure Chlamydia Most common bacterial STD in the U S Can cause sterility in men and women In women they bear the greater burden it can lead to pelvic inflammatory disease infertility and also ectopic pregnancy 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 Usually asymptomatic in women some have vaginal discharge burning with urination pain or bleeding with intercourse and lower abdominal pain In men painful urination watery discharge from penis and pain around testicles and lower abdomen Symptoms in both men and women can begin within 5 days of infection Diagnosis and treatment Laboratory tests on a 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 arthritis rashes eye infections PID epididymitis urethritis and gonococcal conjunctivitis an infection in the eyes that can cause blindness if not treated or gonorrheal infection of blood or joints in infants of infected mothers Being infected with gonorrhea increases the likelihood that HIV will be transmitted Can infect throat or rectum through oral or anal sex Symptoms Males incubation period for gonorrhea is brief but generally 2 7 days Thick yellow white discharge and painful urination in men lips of urethral opening might become inflamed and swollen enlargement of lymph nodes 1 2 of men have minor or no symptoms Usually asymptomatic in women may have painful urination increased vaginal discharge and severe menstrual cramp Diagnosis and treatment Microscopic exam of discharge can diagnose infection Oral antibiotics can cure the disease Growing number of drug resistant strains of gonorrhea is a major concern only 1 class of antibiotics remains consistently effective cephalosporin Pelvic Inflammatory Disease PID Occurs when initial infection by gonorrhea or Chlamydia travels upwards into reproductive organs Often serious enough to require hospitalization and surgery 25 of affected women have long term problems such as ectopic pregnancy chronic pelvic pain and recurrent infections Leading cause of infertility in young women risk factors Sex with multiple partners smoking and women who have IUD contraceptive Symptoms Women can be asymptomatic Long and painful periods discharge spotting abdominal pain fever chills nausea and vomiting Diagnosis and treatment Diagnosis made on basis of symptoms physical examination Ultrasound and laboratory tests