Human Immunodeficiency Virus Infection

A retrovirus—human immunodeficiency virus (HIV) type 1—is the primary causative agent of acquired immunodeficiency syndrome (AIDS). The natural history of AIDS begins with infection by the HIV retrovirus, which is detectable only by laboratory tests, and ends with the severely immunocompromised, terminal stage of this disease. Depending on individual variations and the presence of cofactors that influence progression, the time elapsed from acute HIV infection to the appearance of symptoms (mild to severe) to the diagnosis of AIDS and, eventually, to death varies greatly. Transmission of HIV occurs by contact with infected blood or body fluids and is associated with identifiable high-risk behaviors.

Causes

HIV is transmitted by direct inoculation during intimate sexual contact, especially with the mucosal trauma of receptive anal intercourse; transfusion of contaminated blood or blood products (a risk diminished by routine testing of all blood products); sharing of contaminated needles; and transplacental or postpartum transmission from infected mother to fetus (by cervical or blood contact at delivery and in breast milk).

HIV is not transmitted by casual household or social contact. The average time between exposure to the virus and the diagnosis of AIDS is 8 to 10 years, but shorter and longer incubation times have been recorded. Most people develop antibodies within 6 to 8 weeks of contracting the virus.

Complications

Complications from AIDS include immunodeficiency, which may cause opportunistic infections and unusual cancers; autoimmunity, which may lead to lymphoid interstitial pneumonia, arthritis, hypergammaglobulinemia, and production of autoimmune antibodies; and neurologic dysfunction, which results in AIDS dementia complex, HIV encephalopathy, and peripheral neuropathies.

Assessment Findings

HIV infection manifests itself in many ways. The infected person usually experiences a mononucleosis-like syndrome, which may be attributed to flu or other virus and then may remain asymptomatic for years. In this latent stage, the only sign of HIV infection is laboratory evidence of seroconversion.

When signs and symptoms appear, they may present as persistent generalized adenopathy, nonspecific signs and symptoms (weight loss, fatigue, night sweats, and fevers), neurologic symptoms resulting from HIV encephalopathy, or opportunistic infection or cancer.

Only gold members can continue reading. Log In or Register to continue