Clinical Symptoms of AIDS

Chapter 8 This chapter outlines the different types of immune system alterations, specifically hypersensitivity reactions and deficiencies in immunity. Hypersensitivity reactions can be categorized by the immunologic mechanism causing the disease and the source of the antigen being attacked by the immune system. There are four main types of hypersensitivity reactions: type I (IgE-mediated reactions), type II (tissue-specific reactions), type III (immune complex-mediated reactions), and type IV (cell-mediated reactions). Clinical Symptoms of AIDS Severe weight loss and anorexia Kaposi sarcoma lesions Perianal lesions of herpes simplex infection Deterioration of vision from cytomegalovirus retinitis leading to blindness Treatment and prevention of AIDS HIV/AIDS treatment guidelines are published by the National Institutes of Health (NIH) Approved AIDS medications are classified by mechanism of action Current treatment regimen is a combination of drugs called antiretroviral therapy (ART) Specific regimens are adapted based on various parameters Limitations of drug therapy for AIDS Drug therapy is not curative because HIV incorporates into the genetic material of the host Drug administration may need to continue for the lifetime of the individual HIV may persist in organs where antiviral drugs are not as effective, such as the central nervous system (CNS) Did You Know? Iblaizumab-Uiyk and Multidrug-Resistant HIV-1 Ibalizumab-uiyk (Trogarzo) has been approved for treatment of multidrug-resistant HIV Ibalizumab is a drug that blocks HIV-1 entry into CD4+ T cells while preserving normal immunologic function It is the first CD4-directed postattachment HIV-1 inhibitor and the first humanized monoclonal antibody for the treatment of HIV/AIDS In clinical trials, it has demonstrated anti-HIV-1 activity without causing immunosuppression Immune reconstitution inflammatory syndrome (IRIS) Occurs when the immune system recovers after HIV treatment Results in overwhelming inflammatory response Pulmonary IRIS associated with opportunistic infections like Mycobacterium tuberculosis Long-term toxicity of ART drugs Increased risk for cardiovascular disease, metabolic disorders, and organ failure Some individuals fail to fully reconstitute their immune system or develop chronic immune activation Chronic immune activation exacerbates clinical disease Transmission of HIV from mother to child Risk reduced with ART during pregnancy Diagnosis in young children can be difficult due to the presence of maternal antibodies Testing for antibodies against HIV can be performed until 18 months Neurologic involvement in HIV infection in babies and children More aggressive than in adults HIV encephalopathy occurs and is part of AIDS diagnosis in children Symptoms include developmental delays, motor deficits, brain growth impairment Treatment for HIV infection in infants and children Treatment must begin at the time of diagnosis Criteria for treatment similar to older children Development of recurrent or unusual infections in immunodeficiency Recurrent or unusual infections are the clinical hallmark of immunodeficiency Immunodeficiency weakens the immune system's ability to fight off infections Common infections in defects in cell-mediated immune response vs humoral immune response Defects in cell-mediated immune response: These individuals are more susceptible to infections caused by intracellular pathogens, such as tuberculosis and fungal infections Defects in humoral immune response: These individuals are more prone to infections caused by extracellular pathogens, such as bacterial and viral infections How HIV causes immune suppression HIV attacks and destroys CD4 T cells, which are crucial for the immune system's ability to respond to infections As a result, the immune system becomes weakened and is unable to effectively fight off opportunistic infections