AIDS Dr. Meg-angela Christi Amores

AIDS Etiologic agent: – HIV (Human Immunodeficiency Virus) – 2 types: HIV 1 and HIV 2 – Most common cause: HIV 1

Replication and CD-4 involvement

Classification categorizes persons on the basis of clinical conditions associated with HIV infection and CD4+ T lymphocyte counts

Classification Category A – Asymptomatic HIV infection – Persistent generalized lymphadenopathy – Acute (primary) HIV infection with accompanying illness or history of acute HIV infection

Category B – Bacillary angiomatosis Candidiasis, – oropharyngeal (thrush) – Candidiasis, vulvovaginal; persistent, frequent, or poorly responsive to therapy – Cervical dysplasia – Constitutional symptoms – Hairy leukoplakia – oral Herpes zoster (shingles), involving at least two distinct episodes or more than one dermatome – Idiopathic thrombocytopenic purpura – Listeriosis – Pelvic inflammatory disease, particularly if complicated by tuboovarian abscess – Peripheral neuropathy

Category C: Conditions listed in the AIDS surveillance case definition.

The definition of AIDS is complex Not focus on whether or not patient fulfills strict definition View HIV disease as a spectrum

Transmission transmitted by both homosexual and heterosexual contact; by blood and blood products; and by infected mothers to infants either intrapartum, perinatally, or via breast milk

Sexual Transmission HIV infection is predominantly a sexually transmitted disease (STD) worldwide Mostly male to male contact in US But heterosexual is more common in developing countries male circumcision is associated with a lower risk of HIV infection among men

Sexual Transmission concentrate in the seminal fluid, esp. in genital inflammatory states such as urethritis and epididymitis, conditions closely associated with other STD cervical smears and vaginal fluid strong association of HIV transmission with receptive anal intercourse More male to female than female to male

Other sexual issues Oral sex is a much less efficient mode of transmission of HIV than is receptive anal intercourse association of alcohol consumption and illicit drug use with unsafe sexual behavior leads to an increased risk of sexual transmission of HIV

Transmission by blood and blood products receive HIV-tainted blood transfusions transplanted tissue sharing injection paraphernalia such as needles, syringes, the water in which drugs are mixed Do not require IV (intravenous pucture), even SC and IM can transmit

Occupational Transmission: Health workers small, but definite, occupational risk 600,000–800,000 health care workers are stuck with needles in the US risk of HIV transmission following skin puncture from a needle or a sharp object that was contaminated with blood from a person with documented HIV infection is ~0.3% and after a mucous membrane exposure it is 0.09%

Maternal-Fetal/Infant Transmission during pregnancy, during delivery, or by breast-feeding HIV can be transmitted to the fetus as early as the first and second trimester most commonly in the perinatal period risk of HIV infection via breast-feeding is highest in the early months of breast-feeding

Clinical Manifestations Acute HIV Syndrome – 3–6 weeks after primary infection – fever, skin rash, pharyngitis, and myalgia – usually persist for one to several weeks and gradually subside

Clinical Manifestations The Asymptomatic Stage—Clinical Latency – median time for untreated patients is ~10 years – active virus replication is ongoing and progressive – Ave. rate of CD4+ T cell decline is ~50/uL per year – <200/uL – level at which risk for opportunistic infections is high

Clinical Manifestations Symptomatic Disease – can appear at any time – diagnosis of AIDS is made in anyone with HIV infection and a CD4+ T cell count <200/uL – anyone with HIV infection who develops one of the HIV-associated diseases considered to be indicative of a severe defect in cell-mediated immunity

AIDS - symptomatic Pneumocystis jiroveci – pneumonia MTB Toxoplasmosis – Varicella Cryptococcus neoformans – cryptococcosis Histoplasma capsulatum

Management ELISA - standard blood screening test Antibodies to HIV generally appear in the circulation 2–12 weeks following infection most commonly used confirmatory test is the Western blot Monitoring: CD4+ T Cell Counts Indicator of the immediate state of immunologic competence of the patient

Management Combination antiretroviral therapy (ART), or highly active antiretroviral therapy (HAART), is the cornerstone of management of patients Reverse Transcriptase Inhibitors (Ziduvudine) Protease Inhibitors (Saquinavir) Entry Inhibitors Suppression of HIV replication is an important component in prolonging life