infectious diseases
Human Immunodeficiency Virus (HIV) Infection
Prognosis for HIV Infection
Risk of AIDS, death, or both is predicted by the CD4 count in the short term Plasma HIV RNA level in the longer term 50/mcL. However, with effective treatment, the HIV RNA level decreases to undetectable levels, CD4 counts often increase dramatically, and risk of illness and death falls but remains higher than that for age-matched populations not infected with HIV ( Prognosis references ). Hence, prompt diagnosis of HIV before the disease is too advanced and immediate initiation of HIV treatment are essential to prognosis. Another, less well-understood prognostic factor is the level of immune activation as determined by evaluating the expression of activation markers on CD4 and CD8 lymphocytes. Activation, which may be caused by leakage of bacteria across the HIV-damaged colonic mucosa, is a strong prognostic predictor but is not used clinically because this test is not widely available and antiretroviral therapy changes the prognosis, making this test less important. A subgroup of people infected with HIV (termed long-term nonprogressors) remains asymptomatic with high CD4 counts and low HIV levels in the blood without antiretroviral treatment. These people usually have vigorous cellular and humoral immune responses to their infecting HIV strain as measured by assays in vitro. The specificity of this effective response is shown by the following: When these people acquire a superinfection with a second strain of HIV to which their immune response is not as effective, they convert to a more typical pattern of progression. Thus, their unusually effective response to the first strain does not apply to the second strain. These cases provide a rationale for counseling people infected with HIV that they still need to avoid exposure to possible HIV superinfection through unsafe sex or needle sharing. Cure of HIV infection has not been thought possible, and thus lifelong drug treatment is considered necessary. Patients living with HIV infection should be urged to take their antiretroviral drugs consistently. An instance of a possible functional cure was widely reported in an infant with transient eradication of replication-competent HIV after about 15 months of antiretroviral therapy ( Prognosis references ). However, HIV replication subsequently resumed ( Although antiretroviral therapy has dramatically increased life expectancy for patients with AIDS, many patients still deteriorate and die. Death may result from the following: Inability to take ART consistently, resulting in progressive immunosuppression Occurrence of untreatable opportunistic infections and cancers Liver failure due to hepatitis B or C Accelerated aging and age-related disorders Non-AIDS–related cancers that occur at a higher rate in patients with otherwise well-controlled HIV infection Death is rarely sudden; thus, patients usually have time to make plans. Nonetheless, patients should record their plans for health care early, with clear instructions for end-of-life care. Other legal documents, including Durable power of attorney for health care and wills, should be in place. As patients near the The Dying Patient , clinicians may need to prescribe drugs to relieve pain, anorexia, agitation, and other distressing symptoms. The profound weight loss in many people during the last stages of AIDS makes good skin care difficult. The comprehensive support provided by hospice programs helps many patients because hospice providers are unusually skilled at symptom management, and they support caregivers and patient autonomy. 