958 HIV: The Initial Physician-Patient Encounter Mayo Clin Proc, September 2002, Vol 77 Table 1. Indications for HIV Screening* High-risk behaviors Mu

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1 Mayo Clin Proc, September 2002, Vol 77 HIV: The Initial Physician-Patient Encounter 957 Concise Review for Clinicians Human Immunodeficiency Virus: The Initial Physician-Patient Encounter MARY J. KASTEN, MD Human immunodeficiency virus (HIV) infection is increasingly becoming a disease managed by HIV specialists. However, all primary care physicians have an important role that can affect the epidemic in the United States. These physicians must be able to appropriately identify patients at risk, screen for and diagnose HIV, provide counsel, and refer those who are infected to specialists. The primary care physician will often continue to provide medical care in collaboration with an HIV specialist. The patient will receive optimal care when the primary care physician is knowledgeable regarding HIV and the evaluation of the newly diagnosed patient. Through appropriate screening, evaluation, diagnosis, and counseling, the pri- mary care physician will not only improve the care of the individual patient but also potentially decrease the spread of HIV. This article answers some of the questions that primary care physicians are likely to have when evaluating an adult with newly diagnosed HIV infection. Mayo Clin Proc. 2002;77: AIDS = acquired immunodeficiency syndrome; CMV = cytomegalovirus; EIA = enzyme immunoassay; ELISA = enzyme-linked immunosorbent assay; HAART = highly active antiretroviral therapy; HIV = human immunodeficiency virus; PCP = Pneumocystis carinii pneumonia; PPD = purified protein derivative The treatment of patients diagnosed as having human immunodeficiency virus (HIV) disease is complex and constantly changing. Increasingly, specialists are treating patients with HIV. Primary care physicians may also be experts in the care of the HIV-infected patient, but even physicians without HIV expertise have important responsibilities regarding the HIV epidemic and the HIV-infected patient: they are still responsible for counseling patients on preventing infection; they need to recognize the many presentations of HIV so they can give appropriate care and counseling; and they need to be familiar with the basics of HIV management to care for patients who do not have access to, or are uninterested in, specialty care. Primary care physicians with little or no specialty training in HIV disease often have the initial encounter with an adult with HIV. This article uses an illustrative case to address the questions frequently raised when a patient with previously undiagnosed HIV is identified and requires subsequent evaluation. ILLUSTRATIVE CASE Dr W is seeing Ms T, a 35-year-old woman, for a routine examination and for a renewal of her oral contraceptive. She reports being generally well but did have an episode of herpes zoster (shingles) that From the Division of General Internal Medicine and Division of Infectious Diseases and Internal Medicine, Mayo Clinic, Rochester, Minn. A question-and-answer section appears at the end of this article. Individual reprints of this article are not available. Address correspondence to Mary J. Kasten, MD, Division of General Internal Medicine, Mayo Clinic, 200 First St SW, Rochester, MN was treated with acyclovir last month by a physician in the urgent care center. She is no longer experiencing pain. She denies being concerned about HIV infection and reports being in a monogamous relationship with her fiancé. Further questioning reveals that Ms T has had 5 sexual partners, and 1 shortterm relationship was with a man who had a history of intravenous drug use. She has never had an HIV test. Dr W is aware that Ms T s history of multiple sexual partners and her sexual relationship with a partner who was at high risk of being HIV infected through his intravenous drug use places Ms T at increased risk of being infected with HIV. Dr W also notes that Ms T s history of shingles before age 50 years is unusual, but shingles is a common early manifestation of cellular immunosuppression in patients with HIV. He is concerned that Ms T may be HIV infected and decides to offer her screening. WHICH PATIENTS SHOULD BE SCREENED FOR HIV? Identifying at-risk patients and screening as appropriate are the most important aspects of HIV care that non HIV specialists can provide. Unfortunately, studies have shown that physicians often miss opportunities for screening, and thus many patients remain undiagnosed for years. 1,2 During these years, the HIV-positive patient is at risk of unknowingly infecting others and of developing illnesses that may be prevented with appropriate care. Physicians need to know that HIV is not an unusual illness and is frequently overlooked unless specifically considered. All patients need to be questioned regarding high-risk behaviors. All patients with the risk factors or history noted in Table 1 Mayo Clin Proc. 2002;77: Mayo Foundation for Medical Education and Research

2 958 HIV: The Initial Physician-Patient Encounter Mayo Clin Proc, September 2002, Vol 77 Table 1. Indications for HIV Screening* High-risk behaviors Multiple sexual partners History of giving or obtaining sex for drugs or money History of anal intercourse History of sex with an intravenous drug user, person at risk for HIV, or person with known HIV infection History of a sexually transmitted disease History of intravenous drug use History of having received blood or blood products before 1985 Clinical signs/clues Desires HIV screening Active tuberculosis Herpes zoster in a healthy person <50 y New severe psoriasis or other new unexplained severe skin disorder History of hepatitis B or C Cervical cancer or HPV infection Thrush not related to recent antibiotic use Unexplained cachexia or weight loss Diffuse lymphadenopathy Unexplained thrombocytopenia, leukopenia, or anemia Unusual or prolonged unexplained viral-like illness (consider acute HIV) History of an opportunistic or unusual infection in an otherwise healthy individual Prolonged unexplained illness despite evaluation *HIV = human immunodeficiency virus; HPV = human papillomavirus. need to be screened for HIV infection. When HIV is clinically suspected, physicians should not be dissuaded from obtaining consent and testing for HIV, even if high-risk behavior was not reported by the patient. By having a low threshold to screen for HIV and to provide education regarding HIV transmission, primary care physicians can substantially affect the epidemic. Usually, any patient who asks for an HIV test should be screened. Patients are often unwilling to admit to a risk factor for HIV, yet they want to be tested. This request provides an opportunity to educate the patient on how HIV is transmitted and how the risk of transmission can be decreased. If a patient denies risk factors, he or she can be informed that the risk of HIV appears to be extremely low but that a screening test is reasonable if they remain concerned. Patients with positive test results frequently later admit to risk factors that they previously denied. Physicians should obtain informed consent before testing for HIV. Written consent is not required in Minnesota but is a legal requirement in some states. Dr W discusses his concerns with Ms T, and she agrees to be tested for HIV. WHAT TEST SHOULD BE ORDERED TO SCREEN FOR HIV? Patients who are being initially screened for chronic HIV infection should have an enzyme-linked immunosorbent assay or enzyme immunoassay (ELISA or EIA) antibody test. Serum-, saliva-, and urine-based tests are available. Physicians must remember that, since these are antibody tests, they can be false negative early in the illness but are usually positive 6 months after infection. Patients need to be educated regarding the limitations of the ELISA or EIA antibody test and instructed that they should be rechecked in 6 months if they have had a recent potential exposure and the test results were negative. The specificity of the serum ELISA or EIA is higher than 99.5% with most tests. 3 However, false-positive results can occur, and all positive results must be confirmed with a highly specific test. Both the HIV Western blot and HIV indirect immunofluorescence assay are approved for confirmatory testing. Most US institutions use the standard serum ELISA and Western blot tests. The Western blot can be done with the use of serum or saliva. The specificity of the Western blot, which is most commonly used in the United States, is close to 100% under controlled settings but depends on the skill and experience of the laboratory personnel. 4-6 Indeterminate Western blot test results may indicate an evolving antibody response in recently infected patients, but in low-risk patients, it usually represents the presence of nonspecific antibodies. Repeated Western blot testing and consultation with a physician knowledgeable about HIV testing is recommended when the result is indeterminate. Home HIV tests and rapid HIV tests using either a colorimetric assay or an EIA-based test have sensitivities and specificities similar to the standard serum ELISA and should be confirmed with a more specific test, such as the Western blot. 7 Blood banks use a third-generation ELISA that is less specific and more sensitive than the standard serum ELISA and therefore generates more false-positive results. This test can detect HIV antibodies earlier than the standard ELISA or EIA test but must also be confirmed with a more specific test. 8,9 Diagnosing acute HIV infection is even more challenging than diagnosing chronic HIV infection. The presentation of acute HIV is nonspecific and similar to a number of other viral infections. The most common signs and symptoms of acute HIV infection include fever, weight loss, sore throat, rash, myalgia, lymphadenopathy, and oral ulcers. 10 A diagnosis of acute HIV infection requires a negative ELISA or EIA antibody test or an indeterminate Western blot test, along with either a positive P24 antigen or a positive viral load. Viral load testing measures the number of HIV particles in plasma, usually by determining the quantity of plasma HIV-RNA. A recent study determined the P24 antigen to be 100% specific but only 88% sensitive, while the viral load was 100% sensitive and 88% specific for acute symptomatic HIV. 11 Of note, in this study, all false-positive viral loads were less than 2000 copies/ml, and all true-

3 Mayo Clin Proc, September 2002, Vol 77 HIV: The Initial Physician-Patient Encounter 959 positive viral loads for acute infection were higher than 100,000 copies/ml. Without a high index of suspicion, many cases of acute HIV will be missed. Ms T is tested and both HIV ELISA and Western blot tests are positive. Dr W does not relay such important information by telephone and appropriately arranges a follow-up appointment to discuss the test results with Ms T. HOW DOES A PHYSICIAN DISCUSS A POSITIVE HIV TEST RESULT WITH THE PATIENT? The physician needs to be prepared for a positive result and have the time and knowledge at this visit to support and counsel the patient appropriately. Relaying the diagnosis of HIV infection is often more difficult than sharing a diagnosis of cancer or other serious medical news with a patient because of the stigma associated with HIV infection. The patient may be reluctant to tell friends and family, who would usually provide support in difficult times, about the diagnosis. The physician must balance honesty with realistic optimism and hope during this discussion. The truth that our understanding of HIV, the prognosis, and treatment are all undergoing rapid advances can be emphasized. The physician can also guide the patient, if needed, to organizations that provide emotional support and social workers or nurses who may be able to help the patient through this particularly stressful time. The physician needs to know what resources are available for patients who urgently need help with food, housing, financial, or emotional issues. The physician cannot provide all this care but must be prepared to make appropriate referrals. The patient s knowledge regarding HIV needs to be assessed, and more importantly, the patient needs to be educated on how HIV is transmitted and how to prevent further spread of the illness. Ideally, much of this discussion can occur during the visit when the decision is made to test for HIV. Even when the patient denies particular risk factors, the physician should provide education on the use of condoms and sterile needles. Time should be set aside during future visits to review information regarding transmission and to educate the patient further about the disease, once the patient has emotionally recovered from the shock of the diagnosis. Patients may have acute problems that require additional thought and treatment once the diagnosis of HIV is known. Perhaps what previously looked like atypical pneumonia in a young adult who would probably respond to a macrolide is now thought to be Pneumocystis carinii pneumonia (PCP). The HIV diagnosis, especially once the CD4 cell count is known, may change or broaden the differential diagnosis for many acute and chronic problems. Ms T asks Dr W if he will continue to be her physician. Dr W reassures her that he will continue to act as her primary physician but explains that she will also need evaluation by an HIV specialist since Dr W has little HIV expertise. Dr W asks a colleague what additional history, examination, and laboratory studies would be important to obtain in this newly diagnosed patient. WHAT BASELINE HISTORY IS IMPORTANT TO OBTAIN IN A NEWLY DIAGNOSED HIV-INFECTED PATIENT? Once the patient has acknowledged the diagnosis, a baseline history should be obtained. Although much of this history is usually not obtained at the appointment when the diagnosis is relayed, it is important to obtain the history soon if the physician plans to provide ongoing care. The baseline history should include a general medical history, information on any unusual illnesses in the past that in retrospect may now be thought to be HIV related, family history, social history, medications, allergies, and a complete review of systems. Previous sexually transmitted illnesses, hepatitis, history of tuberculosis, exposure to tuberculosis, results of previous purified protein derivative (PPD) tuberculin tests, and history of infections should be noted. This information may be useful in prioritizing a differential diagnosis when the patient presents with new symptoms, signs, or laboratory abnormalities. Immunization history should be documented. Sexual and reproductive history, as well as current contraception/condom use (and attitude toward use) are also important parts of the history that might, in other settings, be ignored. The patient needs to be counseled that sexual partners must be screened for HIV. Travel to areas of endemic infection (eg, the southwestern United States, where coccidioidomycosis is most often seen), occupational history, hobbies, pets, and lifestyle can all provide clues to future potential infection risk. This information can be invaluable in the future when the patient presents with an unknown illness. It is helpful to document this information shortly after the initial diagnosis and to have it easily accessible for follow-up visits. The patient s risk behavior should be ascertained. The patient s need and willingness to change such behavior should also be addressed. The patient s substance abuse, past and present, should be reviewed. The willingness of the patient to address active substance abuse should be noted; if willing, the patient should be referred to appropriate professionals. Substance abuse and difficulty complying with antiretroviral treatment are often linked. Patients and physicians need to be aware of this issue.

4 960 HIV: The Initial Physician-Patient Encounter Mayo Clin Proc, September 2002, Vol 77 Table 2. Conditions Indicative of AIDS* Candidiasis of esophagus, trachea, bronchi, or lungs Cervical cancer, invasive Coccidioidomycosis, extrapulmonary Cryptococcosis, extrapulmonary Cryptosporidiosis with diarrhea lasting >1 mo Cytomegalovirus of any organ other than liver, spleen, or lymph nodes Herpes simplex with mucocutaneous ulcer lasting >1 mo or bronchitis, pneumonitis, esophagitis Histoplasmosis, extrapulmonary HIV-associated wasting Isosporiasis with diarrhea lasting >1 mo Kaposi sarcoma Lymphoma of the brain Lymphoma, non-hodgkin of B-cell or unknown immunologic phenotype and histology showing small, noncleaved lymphoma or immunoblastic sarcoma Mycobacterium avium complex or M kansasii, disseminated Nocardiosis Pneumocystis carinii pneumonia Pneumonia, recurrent bacterial ( 2 episodes in 12 mo) Progressive multifocal leukoencephalopathy Salmonella septicemia (nontyphoid), recurrent Strongyloidiasis, extraintestinal Toxoplasmosis of internal organ Tuberculosis *Adapted from the Centers for Disease Control and Prevention. 12 AIDS = acquired immunodeficiency syndrome; HIV = human immunodeficiency virus. WHAT PHYSICAL EXAMINATION FINDINGS ARE ESPECIALLY IMPORTANT IN THE PATIENT WITH NEWLY DIAGNOSED HIV? All patients with newly diagnosed HIV should have a complete physical examination that establishes a baseline, and this is an opportunity for the physician to look for evidence of HIV-related conditions. The list of possible physical findings that may suggest an HIV-related condition is extensive. The physician should give particular care to the skin examination by looking for evidence of Kaposi sarcoma, unusual nodules, ulcers, or other lesions suggestive of an infection, and for more ordinary skin diseases such as psoriasis and seborrheic dermatitis that have the potential to become exacerbated as immunosuppression progresses. The patient s mouth should be examined meticulously because HIV-related conditions including Kaposi sarcoma may be seen, thrush is common, and dental hygiene needs to be assessed. A careful search for lymphadenopathy, splenomegaly, abnormal breathing sounds, and a cardiac rub are all important during the initial examination. A baseline neurologic examination, including a mental status examination, should be performed and documented. Women should undergo gynecologic examinations, including a Papanicolaou test, screening for gonorrhea and chlamydia, and inspection for ulcers and other genital lesions. A rectal examination should be performed. The oral cavity and/or rectum need to be screened for sexually transmitted diseases if the patient has engaged in oral sex and/or receptive anal sex, respectively. Urethral specimens should be tested for chlamydia in asymptomatic men who have engaged in insertive sex. An anal Papanicolaou test should be considered for patients with a history of receptive anal sex. Additional evaluation is needed for patients with urologic or gynecologic symptoms. WHAT LABORATORY TESTS SHOULD BE ORDERED FOR THE ASYMPTOMATIC PATIENT WITH NEWLY DIAGNOSED HIV? Physicians beliefs vary regarding which tests besides a viral load and CD4 cell count are important to obtain as a baseline. Reasonable baseline testing includes a complete blood cell count with differential, creatinine level, liver function tests, lipid values, and glucose level. Hepatitis serologies, syphilis serology, Toxoplasma IgG, and cytomegalovirus (CMV) IgG for women and heterosexual men should be checked. Men who have had multiple male sexual partners are uniformly positive for CMV, and a CMV IgG is not necessary in this setting. Patients with CD4 cell counts lower than 50 cells/mm 3 should be referred to an ophthalmologist who has experience screening for retinal opportunistic infections, particularly CMV. A PPD test should be obtained unless the patient has previously had a positive test result. Dr W orders the previously mentioned tests and asks Ms T to return in a week for additional evaluation. He obtains a thorough history and performs a complete physical examination. He notes that the results of Ms T s blood tests are normal except that her CD4 cell count is 420 cells/mm 3 and her viral load is 25,000 copies/ml. Her CMV IgG and Toxoplasma IgG results are positive, but her other serologic and PPD results are negative. Dr W reassures Ms T that, although her immune system is not normal, development of acquired immunodeficiency syndrome (AIDS) and the illnesses associated with AIDS is not an immediate concern. HOW DOES THE PHYSICIAN ASSESS THE PROGNOSIS AND THE RISK OF AIDS DEVELOPING IN A PATIENT NEWLY DIAGNOSED WITH HIV? Many patients are confused about the difference between HIV infection and AIDS. A patient has AIDS when both an HIV infection and an AIDS-defining illness are present (Table 2) or when the CD4 cell count is lower than 200 cells/mm 3. The average duration of HIV infection before an untreated patient develops AIDS is about 10 years but can vary greatly. The viral load and CD4 cell count together can be very helpful in assessing a patient s prognosis. The CD4 cell count in chronic infections reflects fairly well the level of cell-mediated immune function and the progression of the disease, while the viral load

5 Mayo Clin Proc, September 2002, Vol 77 HIV: The Initial Physician-Patient Encounter 961 reflects how quickly the disease is progressing. During acute infection, both CD4 cell counts and viral loads show rapid changes that are unrelated to long-term prognosis. Table 3 illustrates how these tests can be used together in a chronic infection to estimate a patient s risk of developing AIDS over the next decade. Information regarding the likely timing of initial infection and trends in the CD4 cell count can also help assess how rapidly the illness is progressing. Ms T asks what medications or vaccines she should take to stay healthy. WHAT IMMUNIZATIONS ARE APPROPRIATE FOR A PATIENT WITH NEWLY DIAGNOSED HIV? Patients who have a reasonable CD4 cell count and are otherwise generally healthy should respond well to immunizations. They should have their immunization history reviewed, and all routine immunizations such as tetanus should be updated. Such patients should be given the pneumococcal vaccine and, if serologically negative, be immunized against hepatitis B. All patients who are infected with hepatitis B or C, have other underlying liver disease, or are at risk of hepatitis A because of their work or travel should be immunized against hepatitis A. The measles, mumps, and rubella vaccine is a live combination virus vaccine that has been given safely to many HIV-infected children, 14 but it and other live-virus vaccines, including varicella, should be deferred in an HIV-positive adult until the individual s situation (risk vs potential benefit) can be reviewed by an expert. Delaying immunizations in patients with low CD4 cell counts may be best if highly active antiretroviral therapy (HAART) is likely to be given in the near future. HAART may minimize the effect, if any, of the vaccine on stimulating HIV replication and may in time improve the immune response. Patients who will be deferring treatment for a prolonged period should be immunized, even if severely immunosuppressed. WHEN ARE PROPHYLACTIC MEDICATIONS NEEDED TO PREVENT OPPORTUNISTIC INFECTIONS? Prophylaxis against opportunistic infections is an area in which the primary care physician with minimal knowledge of HIV can often substantially affect a patient s health. Early in the HIV epidemic, patients were expected to develop opportunistic infections. However, even before HAART, a considerable impact had been made on the incidence of several opportunistic infections for which effective prophylaxis is available. Pneumocystis carinii pneumonia prophylaxis is indicated if the patient has a CD4 cell count lower than 200 cells/mm 3, has oral candidiasis, or has had an unexplained fever for more than 2 weeks. Prophylaxis against toxoplasmosis is necessary if Table 3. Risk of Development of an AIDS-Defining Illness* Risk of devloping AIDS Baseline Baseline CD4 (%) viral load cell count Within Within (copies/ml) (/mm 3 ) 3 y 9 y <500 < > ,001-30, > >30, > *Data from Mellors et al. 13 AIDS = acquired immunodeficiency syndrome. Viral load in this study was quantified with a sensitive branched-dna assay (Chiron Corp, Emeryville, Calif). In this study, AIDS was defined according to the 1987 Centers for Disease Control and Prevention definition and does not include asymptomatic individuals with CD4 cell counts <200 cells/mm 3. the patient s Toxoplasma IgG antibody results are positive and the CD4 cell count is lower than 100 cells/mm 3. This can usually be accomplished with trimethoprim-sulfamethoxazole, which is also given for PCP prevention. Mycobacterium avium-intracellulare prophylaxis is indicated if the CD4 cell count is lower than 50 cells/mm 3. Azithromycin given weekly is the most common regimen for Mycobacterium avium-intracellulare prophylaxis because it is simple and usually well tolerated. Prophylaxis against tuberculosis, usually with isoniazid, should be given if the PPD induration is larger than 5 mm with no history of previous treatment, if the patient has a history of a positive PPD without treatment, or if the patient has a known exposure to an active case. Additional recommendations regarding how HIV-infected patients can decrease their risk of acquiring other infections are detailed in the 1999 US Public Health Service and Infectious Diseases Society of America guidelines for the prevention of opportunistic infections in persons infected with human immunodeficiency virus. 15 Dr W recommends a pneumococcal vaccine, a routine tetanus booster, and the hepatitis B series. He tells Ms T and her fiancé that in the future, Ms T may need medication to prevent other infections, but currently they are not needed. Her fiancé questions the need for urgent referral to an HIV expert for anti-hiv medications. HOW URGENT IS ANTIRETROVIRAL THERAPY FOR PATIENTS WITH NEWLY DIAGNOSED HIV? Initiation of antiretroviral therapy in the asymptomatic patient is rarely urgent. The only exception is the patient with acute HIV in whom the immune system may be preserved. Such patients should be referred as quickly as possible to an HIV expert and considered for enrollment in a study.

6 962 HIV: The Initial Physician-Patient Encounter Mayo Clin Proc, September 2002, Vol 77 Patients who are symptomatic with an HIV-related condition should be referred to an HIV expert for consideration of treatment. Expert opinion varies regarding what CD4 cell count warrants antiretroviral therapy in an asymptomatic patient. The physician trying to decide whether to start antiretroviral therapy should also consider the patient s values and lifestyle. HIV treatment naïve patients who are immunologically and virologically stable can usually be observed for some time, and initiation of HAART with its possible toxicities can be delayed. The physician needs to remember that the initial therapy chosen is the patient s best chance at long-term success. Patients often need to be reassured that they will do better if therapy decisions are delayed until they have had time to adjust to their illness and are ready to make the commitment to therapy that longterm success demands. Dr W agrees that a referral is reasonable but reassures both Ms T and her fiancé that urgent treatment of the virus is unnecessary and that she has likely been infected and asymptomatic for years. He explains to them that the HIV expert may even recommend delaying treatment for some time. He offers HIV testing to her fiancé and again discusses the importance of condoms to help prevent transmission of HIV to her fiancé and to decrease Ms T s risk of acquiring other sexually transmitted illnesses. SUMMARY HIV is an illness that makes great demands of primary care physicians. An excellent resource containing a wealth of HIV information and useful links appropriate for both generalists and experts in HIV care is the University of California San Francisco s Web site ( Primary care physicians must be knowledgeable regarding diagnosis of both acute and chronic HIV and must know how to counsel patients once the diagnosis is made. The physician must be prepared to provide ongoing care, usually in conjunction with an HIV specialist. The first discussion of the HIV diagnosis is often one of the most important and memorable encounters with physicians that a patient will ever experience. When knowledge and compassion are included in this initial discussion, the patient often has an easier time accepting the diagnosis and is provided with information that will help prevent the further spread of HIV. Through appropriate counseling and care, primary care physicians have an opportunity to do a great service to the entire community in helping decrease the spread of HIV. REFERENCES 1. Freedberg KA, Samet JH. Think HIV: why physicians should lower their threshold for HIV testing. Arch Intern Med. 1999;159: Porter K, Wall PG, Evans BG. Factors associated with lack of awareness of HIV infection before diagnosis of AIDS. BMJ. 1993; 307: Centers for Disease Control and Prevention. Update: serologic testing for HIV-1 antibody United States, 1988 and MMWR Morb Mortal Wkly Rep. 1990;39: Gerber AR, Valdiserri RO, Johnson CA, Schwartz RE, Hancock JS, Hearn TL. Quality of laboratory performance in testing for human immunodeficiency virus type 1 antibody: variables associated in multivariate analyses. Arch Pathol Lab Med. 1991;115: Polesky HF, Hanson MR. Human immunodeficiency virus type 1 proficiency testing: the American Association of Blood Banks/ College of American Pathologists Program. Arch Pathol Lab Med. 1990;114: Centers for Disease Control and Prevention. Interpretation and use of the Western blot assay for serodiagnosis of human immunodeficiency virus type 1 infections. MMWR Morb Mortal Wkly Rep. 1989;38(suppl 7): Malone JD, Smith ES, Sheffield J, et al. Comparative evaluation of six rapid serological tests for HIV-1 antibody. J Acquir Immune Defic Syndr. 1993;6: Busch MP, Satten GA. Time course of viremia and antibody seroconversion following human immunodeficiency virus exposure. Am J Med. 1997;102(5B): Zaaijer HL, v Exel-Oehlers P, Kraaijeveld T, Altena E, Lelie PN. Early detection of antibodies to HIV-1 by third-generation assays. Lancet. 1992;340: Schacker T, Collier AC, Hughes J, Shea T, Corey L. Clinical and epidemiologic features of primary HIV infection [published correction appears in Ann Intern Med. 1997;126:174]. Ann Intern Med. 1996;125: Daar ES, Little S, Pitt J, et al, Los Angeles County Primary HIV Infection Recruitment Network. Diagnosis of primary HIV-1 infection. Ann Intern Med. 2001;134: Centers for Disease Control and Prevention Revised classification system for HIV infection and expanded surveillance case definition for AIDS among adolescents and adults. MMWR Recomm Rep. 1992;41(RR-17): Mellors JW, Munoz A, Giorgi JV, et al. Plasma viral load and CD4 + lymphocytes as prognostic markers of HIV-1 infection. Ann Intern Med. 1997;126: McLaughlin M, Thomas P, Onorato I, et al. Live virus vaccines in human immunodeficiency virus-infected children: a retrospective survey. Pediatrics. 1988;82: US Public Health Service (USPHS) and Infectious Diseases Society of America (IDSA) USPHS and IDSA guidelines for the prevention of opportunistic infections in persons infected with human immunodeficiency virus. MMWR Recomm Rep. 1999; 48(RR-10):1-59, Questions About Diagnosis and Initial Evaluation of a Patient With HIV 1. A 37-year-old homosexual man who has a history of multiple partners is now in a monogamous relationship, feels well, and desires HIV testing. Which one of the following laboratory tests is the most appropriate screen for HIV? a. HIV ELISA and CD4 cell count b. HIV ELISA, followed by HIV Western blot antibody test if positive c. HIV ELISA, followed by a viral load test if positive d. HIV ELISA and either viral load test or P24 antigen e. Viral load test and CD4 cell count

7 Mayo Clin Proc, September 2002, Vol 77 HIV: The Initial Physician-Patient Encounter A 24-year-old woman presents with fever, fatigue, headache, sore throat, and enlarged tender cervical and axillary lymph nodes. She denies being at risk for HIV. Her current partner, however, did use intravenous drugs in the past. She has not been using condoms. Her HIV ELISA antibody test is negative. Which one of the following tests would be the most sensitive for diagnosing acute HIV in this situation? a. Western blot HIV antibody test b. P24 antigen c. CD4 cell count d. HIV viral load e. A repeat HIV ELISA antibody test 3. Which one of the following statements regarding HIV infection and laboratory testing is false? a. With chronic HIV infection, the CD4 cell count is a reasonable surrogate marker for the progression of the disease and the degree of immunosuppression b. With acute HIV infection, the CD4 cell counts and viral loads show rapid changes that are unrelated to long-term prognosis c. With chronic HIV infection, the viral load is the best marker for the degree of immunosuppression d. With chronic HIV infection, the CD4 cell count and viral load when used together are very useful in estimating prognosis without treatment e. With chronic HIV infection, the viral load indicates how fast the disease is likely to progress 4. Which one of the following statements regarding the management of HIV infection is false? a. Prophylaxis against toxoplasmosis and PCP can be accomplished with trimethoprimsulfamethoxazole alone b. Prophylaxis against tuberculosis should be given if the PPD induration is >5 mm and the patient has no history of treatment c. Varicella vaccine should be offered to all HIVinfected patients who have no history of chickenpox d. A pneumococcal vaccine and the hepatitis B series should be considered for all HIV-positive patients e. A PCP prophylaxis is indicated if the CD4 cell count is <200 cells/mm 3 5. Which one of the following statements regarding the initial evaluation of patients with HIV is false? a. A complete history and physical examination of the newly diagnosed HIV patient establishes a baseline and can be a helpful reference when the patient presents with an acute problem b. Substance abuse and difficulties with medication compliance are often linked in patients with HIV c. A baseline gynecologic examination should include not only a Papanicolaou test but also screening for gonorrhea and chlamydia and an inspection for genital lesions d. One of the most important responsibilities primary care physicians have with respect to patients with HIV is to provide appropriate screening and pretest and posttest counseling e. Antiretroviral medication should be started at the time of the initial HIV evaluation for most patients Correct answers: 1. b, 2. d, 3. c, 4. c, 5. e