Life Care Planning for the HIV/AIDS Patient – Classification (I)
It has been nearly 30 years since the first case of what would be called acquired immunodeficiency syndrome (AIDS) was described (CDC, 1981). The Centers for Disease Control and Prevention (CDC) began reporting an unusually high incidence of an uncommon pneumonia, Pneumocystis carinii (PCP), now named Pneumocystis jiroveci, but still referred to as PCP (Stringer et al., 2002). A rare cancer, Kaposi’s sarcoma, was also being seen in the same population, young gay men in San Francisco, New York, and other cities. Thus, AIDS was initially considered a male, homosexual disease that spared heterosexual males, females, and children. Then the number of new cases began increasing rapidly among persons with hemophilia A and other recipients of blood transfusions. A third distinct population of victims emerged from the intravenous drug users’ (IDUs’) community. Prognosis at that time was imminent death, the cause and prevention of which were unknown. Because AIDS was appearing in diverse populations, an infectious agent was suspected as the cause. The mode of transmission seemed to be through sexual contact or blood product exposure (Prusiner, 2002).
By 1983—1984 the pathogen responsible for the progressed disease state of AIDS was identified as human immunodeficiency virus (HIV). Within the next 2 years blood tests became available commercially for diagnosing HIV infection, thus safeguarding the blood supply, allowing the extent of the epidemic and individual infection to be defined and forecast, and eventually the evaluation and monitoring of therapeutic interventions (Montagnier, 2002). The mode of infectious transmission has been delineated as being only via exchange of bodily fluids. Present therapies have extended the life span for the treated HIV patient. Still, neither an absolute cure nor a preventative vaccine (Fauci et al., 2008) has yet been developed and so mortality remains virtually 100%.
Since new infections, at the rate of 6500 per day (Fauci et al., 2008), continue to exceed the number of HIV-related deaths, the population living with HIV infection is burgeoning. UNAIDS estimated that at the end of 2007, 33 million people were living with HIV worldwide (2008).
However, the pandemic is not expected to peak for another 40 to 50 years (Stine, 2008, p. 280). The face of AIDS is changing as the pandemic advances. Heterosexuals now comprise about 95% of all those in the world living with HIV infection (Stine, 2008, p. 175). It follows naturally that “the percentage of women among people living with HIV has remained stable at 50% for several years” (UNAIDS, 2008). In 2007, the portion of the population infected with HIV was comprised of sex workers (60.4%), IDUs (46.1%), and men who have sex with men (MSM) (40.1%) (UNAIDS, 2008). It is now evident that the face of HIV/AIDS is changing from the initial perception that AIDS was a male, homosexual disease to the current reality that HIV is an infection spread by heterosexual contact in the mainstream of society.
Now in the third decade since identification, HIV/AIDS has become a pandemic rivaling the Black Death of the fourteenth century’s bubonic plague. This modern plague is unique among prior bacterial and viral scourges that preferentially afflicted the weak, the very young, and the elderly. AIDS ravages the healthy, young to middle-aged adult population, which is not surprising because HIV is transmitted by exchange of body fluids, primarily during sexual contact. The impact on society is also unique in that this pandemic decimates the workforce and leaves a generation of orphans without a cultural structure to support them.
Epidemiology of HIV/AIDS in the United States
Human immunodeficiency virus type 1 (HIV-1) has been clearly identified as the primary cause of AIDS, which results from the destruction of CD4+ T lymphocytes of the immune system. Another strain of the human retrovirus found primarily in western Africa, HIV-2, also causes AIDS. Unless specifically stated as HIV-2, future references to HIV in this post will be to HIV-1. HIV is classified into clades based on genetic diversity of the strain, and further classified by subtype of clade (Kitchen, 1995). The three clades are lettered M, for Main with subtypes A through K, and the relatively rare O for Outlier, and N for non-M non-O clades primarily found in western Africa (Bartlett & Gallant, 2005; Stine, 2008). Genetic variants have arisen, not because HIV replicates with a higher rate of mutation than is common, but because HIV generates 10 billion virions per day. At this rate, every possible mutation in the HIV genome can be produced every day in every victim. The genetic versatility of HIV permits the virus to become drug resistant and avoid antibody detection by vaccines and disease-screening tests (Johnson, 1998).
Clade M, subtype B, is the most prevalent in the United States, causing 98% of all HIV infections (Weidle et al., 2000). However, another distinguishing characteristic of the modern pandemic is that international travel facilitates communication of the different varieties of HIV to all world regions. The prevalence of strain, clade, and subtype of HIV in every world region can be expected to continue changing over time, making effective treatment regimes, testing protocols, and future vaccines obsolete in record time.
As early as 1983, the U.S. Department of Health and Human Services (DHHS) declared the HIV epidemic to be the nation’s foremost health priority (National Institute of Mental Health, 2000). National vital statistics data are discerning measures of HIV-related mortality and how HIV-related deaths have changed over the course of the HIV epidemic. Currently, HIV is the fifth leading cause of death for Americans between the ages of 25 and 44. This represents a decline in AIDS-related deaths by 70% from the mortality peak in 1995 when HIV was the leading cause of death in this age group (National Center for Health Statistics, 2002; CDC, 2002b). The decline in mortality coincides with the emergence of new HIV therapies in the past two decades. Unfortunately, the rate of new infection has not been similarly reduced. It is estimated that more than 56,000 people in the United States acquire HIV annually. The CDC further reported that an alarming 1.1 million persons were living with HIV by the end of 2006. Perhaps 21% of them were unaware of their infection (2008a, 2008b). These numbers represent a substantial health care burden, loss of work time and resources, and significant case management responsibilities for this population.
The face of the epidemic in the United States in 2006 differed from the world as a whole. The majority of persons who contract HIV infection in the United States are MSM (48%). IDUs represent 19% of those infected, and females who engage in high-risk heterosexual contact account for 18%. In the United States, only 25% of those living with HIV are female. Racial minority communities are disproportionately represented among the infected population, especially blacks, followed by Latinos. Blacks are nearly eight times more likely to become infected than whites, while Latino/Hispanics are almost three times as likely to become infected (CDC, 2008a, 2008b). However, like the global HIV+ population, adults ages 25 to 49 years comprise 70% of those infected in the United States. Historically, pediatric HIV infection is almost entirely due to mother-to-child transmission either before or during birth, or after birth by breastfeeding (CDC, 2002b). This is also true globally.
Transmission of HIV occurs through exchange of body fluids, particularly blood, breast milk, and genital secretions. Risk of transmission is present in sexual encounters, infected needle sticks, blood product and tissue reception, birth, and breastfeeding. Because a vaccine against HIV is not anticipated in the foreseeable future, prevention of new infection cases is limited to behavior modification of high-risk behaviors such as injection drug use and unprotected sexual intercourse and minimizing other risk factors such as genital ulcers, multiple sex partners, and history of sexually transmitted diseases. Postexposure prophylaxis (PEP) is moderately effective in reducing the rate of transmission and generally recommended after a significant intravenous exposure or sexual exposure and to reduce mother-to-child transmission for the fetus of an infected woman who becomes pregnant (Dolin, Masur, & Saag, 2003).
After HIV has been transmitted to a person, there ensues an incubation period of 2 to 3 weeks. The subsequent acute retroviral syndrome lasts 1 to 3 weeks; however, only 50% to 90% of patients are symptomatic in this stage. The range and severity of symptoms in primary HIV infection vary considerably, with an acute mononucleosis-like illness developing in about 40% of patients (Bartlett, 2001). Generally, it is characterized (percent prevalence of symptomology) by fever (96%), adenopathy (swollen lymph nodes, 74%), rash on the body (70%), myalgias (54%), and weight loss (13%). Gastrointestinal disorders include pharyngitis (70%), diarrhea (32%), nausea/vomiting (27%), hepatosplenomegaly (14%), and oropharyngeal candidiasis (thrush, 12%). Neurological symptoms may appear as headache (32%) and other indications such as meningitis, meningoencephalitis, peripheral neuropathy, facial palsy, Guillain-Barre syndrome, brachial neuritis, and cognitive/affective disorders (12%) (Bartlett & Gallant, 2005).
With recovery from the acute retroviral syndrome, an antiviral immune response occurs (seroconversion) and a state of chronic HIV infection is entered that may be clinically asymptomatic, or minimally symptomatic before the development of overt immunodeficiency. This clinical latency period is marked by viral replication within lymphoid tissues and declining numbers of CD4+ lymphocyte cells in the immune system. In an untreated patient, the asymptomatic stage usually continues for 7 to 10 (average of 8) years. However, for reasons that are only beginning to be understood, the disease progresses differently in some people such that slow and rapid progressors to the symptomatic and AIDS stages have been seen clinically. Long-term nonprogressors (LTNPs) comprise about 5% to 10% of the HIV seropositive population and appear not to progress to AIDS status (Stine, 2008, p. 162).
The onset of symptomatic HIV infection may present with any of the previously noted or other conditions indicative of cell-mediated immune deficiency such as, but not limited to, bacillary angiomatosis, pelvic inflammatory disease (PID), idiopathic thrombocytopenic purpura, oral hairy leukoplakia, and herpes zoster involving two episodes or two dermatomes and listeriosis (Bartlett & Gallant, 2005). In addition to these direct effects of viral infection, tumors such as Kaposi’s sarcoma and some rather virulent opportunistic infections (OIs) can appear at this time even though the immune system is only moderately suppressed (e.g., bacterial pneumonia and tuberculosis). Chronic skin conditions such as seborrheic dermatitis, persistent oral or vulvovaginal candidiasis, and herpes simplex may be seen (Powderly, 2001). The immune system is progressively impaired as CD4+ cell counts continue to decline, allowing the clinical expression of an AIDS indicator condition.
In the untreated patient of HIV infection, survival from time of HIV infection is about 10 years. The average time from the diagnosis of an AIDS-defining condition to death is 16 months. For the HIV-positive patient receiving current antiretroviral (ARV) therapy and prophylaxes against OIs, survival and quality of life are appreciably better than those of the untreated HIV patient recounted in this natural history of HIV infection. However, the ARV treatments introduced in the last decade have not been used therapeutically long enough to predict the extended survival they provide (Bartlett, 2001; Masci, 2001; Stine, 2008). It is important to remember that no one ever recovers completely, even though the LTNPs seem not to progress to AIDS. The management of chronic HIV infection is not analogous to the management of chronic pathological, noninfectious conditions such as type II diabetes or hypertension, which do not necessarily result in mortality per se.
The classification, surveillance, and reporting of HIV/AIDS are based on the case definitions for adults and children over the age of 18 months that have been developed by the CDC. The CDC has developed special criteria for infants less than 18 months of age that take into account mother-to-child transmission. The AIDS surveillance case definition was revised in 1985, 1987, and 1993 to incorporate additional illnesses that were found to be associated with HIV infection. The current case definition of AIDS recognizes the following AIDS indicator conditions in adults (CDC, 2008).
AIDS-Defining Conditions (CDC, 2008c)
■ Bacterial infections, multiple or recurrent*
■ Candidiasis of bronchi, trachea, or lungs
■ Candidiasis of esophagus1‘
■ Cervical cancer, invasive*
■ Coccidioidomycosis, disseminated or extrapulmonary
■ Cryptococcosis, extrapulmonary
■ Cryptosporidiosis, chronic intestinal (greater than 1 month’s duration)
■ Cytomegalovirus disease (other than liver, spleen, or nodes), onset at age greater than 1 month
■ Cytomegalovirus retinitis (with loss of vision)1
■ Encephalopathy, HIV related
■ Herpes simplex: chronic ulcers (greater than 1 month’s duration) or bronchitis, pneumonitis, or esophagitis (onset at age older than 1 month)
■ Histoplasmosis, disseminated or extrapulmonary
■ Isosporiasis, chronic intestinal (great than 1 month’s duration)
■ Kaposi sarcoma‘
■ Lymphoid interstitial pneumonia or pulmonary lymphoid hyperplasia complex*1
■ Lymphoma, Burkitt (or equivalent term)
■ Lymphoma, immunoblastic (or equivalent term)
■ Lymphoma, primary, of brain
■ Mycobacterium avium complex or Mycobacterium kansasii, disseminated or extrapulmonary1
■ Mycobacterium tuberculosis of any site, pulmonary,1* disseminated,1 or extrapulmonary1
■ Mycobacterium, other species or unidentified species, disseminated1 or extrapulmonary1
■ Pneumocystis jirovecii pneumonia1
■ Pneumonia, recurrent11
■ Progressive multifocal leukoencephalopathy
■ Salmonella septicemia, recurrent
■ Toxoplasmosis of brain, onset at age older than 1 month1
■ Wasting syndrome attributed to HIV
The 1993 revision (CDC, 1992) added immunologic parameters of CD4+ lymphocyte counts less than 200 cells/mm3 or a CD4+ percentage of total lymphocytes of less than 14% as diagnostic of AIDS for HIV-infected adults and adolescents. By 1993 and 1994 this immunologic criteria, rather than AIDS-defining conditions, resulted in almost half of the AIDS cases reported (Sande & Volberding, 1999). An expansion of the case definition for HIV/AIDS stages the progression of HIV according to the patient’s clinical condition categories (A, B, and C) and CD4+ cell count classes (1, 2, and 3). Because class 3 is an AIDS indicator condition, HIV-positive patients staged as A3 and B3 as well as C1—C3 are defined as having progressed to AIDS (Bartlett, 2001; Bartlett & Gallant, 2005).
Clinical Conditions Categories (CDC, 1992)
- Category A consists of one or more of the conditions listed in the following in an adolescent or adult (greater than or equal to 13 years) with documented HIV infection. Conditions listed in Categories B and C must not have occurred.
- Asymptomatic HIV infection
- Persistent generalized lymphadenopathy
- Acute (primary) HIV infection with accompanying illness or history of acute HIV infection
- Category B consists of symptomatic conditions (not A or C) in an HIV-infected adolescent or adult that are not included among conditions listed in clinical Category C and that meet at least one of the following criteria:
- The conditions are attributed to HIV infection or are indicative of a defect in cell- mediated immunity; or
- The conditions are considered by physicians to have a clinical course or to require management that is complicated by HIV infection. Examples of conditions in clinical Category B include, but are not limited to:
- Bacillary angiomatosis
- Candidiasis, oropharyngeal (thrush)
- Candidiasis, vulvovaginal; persistent, frequent, or poorly responsive to therapy
- Cervical dysplasia (moderate or severe)/cervical carcinoma in situ
- Constitutional symptoms, such as fever (101.3 degrees) or diarrhea lasting greater than 1 month
- Hairy leukoplakia, oral
- Herpes zoster (shingles), involving at least two distinct episodes or more than one dermatome
- Idiopathic thrombocytopenic purpura
- Pelvic inflammatory disease, particularly if complicated by tubo-ovarian abscess
- Peripheral neuropathy
- AIDS indicator condition present (see list of AIDS-defining conditions). Once a Category C condition has occurred, the person will remain in Category C.
CD4 Count Classification (CDC, 1992)
- Greater than or equal to 500 cells/pl
- 200 to 499 cells/pl
- Less than 200 cells/pl
The most recent revision (CDC, 1999) incorporated “the reporting criteria for HIV infection and AIDS into a single case definition.” The definition of HIV infection implemented in 1993 was revised to include HIV screening tests as laboratory evidence of HIV with regard to AIDS- defining conditions for adults, adolescents, or children greater than or equal to 18 months of age. A reportable case of HIV infection must meet at least one of the following criteria:
■ Positive result on a screening test for HIV antibody, for example, repeatedly reactive enzyme immunoassay, followed by a positive result on a confirmatory (sensitive and more specific) test for HIV antibody, for example, Western blot or immunofluorescence antibody test
■ Positive result or report of a detectable quantity on any of the following HIV virologic (nonantibody) tests:
– HIV nucleic acid (DNA or RNA) detection, for example, DNA polymerase chain reaction (PCR) or plasma HIV-1 RNA
– HIV p24 antigen test, including neutralization assay
– HIV isolation (viral culture)
Clinical or Other Criteria
If the previous laboratory criteria are not met, then one of the following must be met:
■ Diagnosis of HIV infection, based on the previous laboratory criteria, that is documented in a medical record by a physician
■ Conditions that meet criteria included in the case definition for AIDS (CDC, 1992)