The reliability and validity of the subjective peripheral neuropathy screen.

Painful sensory neuropathy (PSN) is the most common neurological disorder associated with HIV infection and affects up to 30% of HIV-positive individuals. PSN may develop as a consequence of HIV infection or from the toxic effect of the antiretrovirals. Although several tools have been developed to screen for PSN, their validity and reliability has yet to be established among HIV-positive patients. The Subjective Peripheral Neuropathy Screen (SPNS) is a brief self-report tool that is currently being administered in the AIDS Clinical Trials Group. The objective of this study was to establish the psychometric properties of the SPNS screening tool for the correct identification of PSN in HIV-positive individuals. Specifically the goals were to determine the reliability, the validity, and the diagnostic efficiency of the SPNS in the detection of PSN. Data were abstracted on subjects enrolled in an ongoing natural history cohort. The SPNS was administered to a convenience sample of 39 HIV-positive individuals with PSN and 44 HIV-positive controls. Results showed the SPNS to be internally consistent (Cronbach's alpha = .86). SPNS score differences assessed by t-test were significantly different for individual symptoms of parasthesias, numbness, and pain of the lower extremities, and for severity measures (the Clinical Severity Grade, and the Average Severity Score) between the HIV-positive groups (p < .05). Using Spearman's rank, significant correlations were demonstrated between the neurological exam and the Clinical Severity Grade and the Average Severity Score, the neurological exam and vibratory quantitative sensory testing (QST) only, and the severity measures and vibratory QST only. Sensitivity and specificity analysis demonstrated that numbness of the lower extremities was the symptom with the highest efficiency for correctly classifying PSN. Thus, internal consistency, construct validity, and criterion related validity were confirmed with the SPNS for the correct classification of PSN in HIV-positive individuals.

The two cultures and the health care revolution. Commerce and professionalism in medical care.

The current trend toward the invasion of commerce into medical care, an arena formerly under the exclusive purview of physicians, is seen by the authors as an epic clash of cultures between commercial and professional traditions in the United States. Both have contributed to US society for centuries; both have much to offer in strengthening medical care and reducing costs. At the same time, this invasion by commercialism of an arena formerly governed by professionalism poses severe hazards to the care of the sick and the welfare of communities: the health of the public and the public health. Some of these hazards are briefly listed and reviewed, together with a brief outline of standards that might be established nationally to abate these hazards. A national agency in the private sector is proposed, the National Council on Medical Care, to set standards and provide an approval mechanism that would then be the basis for state enforcement through licensing. Two models for such an initiative are outlined, one based on the National Academy of Sciences as the initiating force, and the other on an initiative provided by a consortium of national charitable foundations interested in health policy. In both cases, wide support from the national foundations would be essential. In the case of the academy model, some government funds might also be available without loss of the freedom of a private-sector initiative. Some operational options for such a national council, its membership, and the conduct of its affairs are briefly outlined as a basis for further discussion.

Dementia in AIDS patients: incidence and risk factors. Multicenter AIDS Cohort Study.

We determined incidence and future projections of dementia after AIDS onset in 492 homosexual men with AIDS in the Baltimore/Los Angeles sites of the Multicenter AIDS Cohort Study, 64 of whom developed dementia. We studied various risk factors for dementia, including demographic and clinical features, medical history, markers of immune status before AIDS, and zidovudine use. During the first 2 years after AIDS, HIV dementia developed at an annual rate of 7%. Overall, 15% of the cohort followed through death developed dementia. The median survival after dementia was 6.0 months. Using a proportional hazards model, risk factors for more rapid development of dementia were lower hemoglobin (relative hazard, 0.59 per additional 2 g/dl; p = 0.0005) and body mass index (relative hazard, 0.64 per additional 5 kg/m2; p = 0.05) 1 to 6 months before AIDS, more constitutional symptoms 7 to 12 months before AIDS (relative hazard, 1.68 per additional symptom, p = 0.005), and older age at AIDS onset (relative hazard, 1.60 per decade older; p = 0.009). In a multivariate model, pre-AIDS hemoglobin remained the most significant predictor of dementia. There were no significant risks defined from demographic characteristics, specific AIDS-defining illnesses, zidovudine use before AIDS, or CD4+ lymphocyte count before AIDS. We project that 12 months after the first AIDS diagnosis, 7.1% of survivors will have dementia. The observed association between anemia, low weight, constitutional symptoms, and dementia suggests a role for cytokines inducing both systemic and neurologic disease.

Regional brain atrophy in HIV-1 infection: association with specific neuropsychological test performance.

Quantified magnetic resonance imaging (MRI) was related to neuropsychological (NP) test scores in an asymptomatic HIV-1 seropositive group, a non-demented AIDS/ARC group, a group of subjects with HIV-1 dementia, and a seronegative control group. The MRIs were quantified using three planimetric measures of brain structure: the bicaudate ratio (a measure of caudate region atrophy), the bifrontal ratio (a measure of frontal region atrophy), and the ventricle to brain ratio (a measure of overall cerebral atrophy). Cognitive performance was assessed with standard NP tests. Significant correlations between the MRI ratios and many of the NP tests were observed. Of the tests grooved pegboard, part B of the trail making test, the verbal fluency test, and the digit span forward were associated with MRI abnormalities. The bicaudate ratio was most closely associated with the NP tests. These findings indicate that ventricular enlargement, especially in the region of the caudate, is closely related to poor NP test performance in HIV-1 infection.

Patterns of cerebral atrophy in HIV-1-infected individuals: results of a quantitative MRI analysis.

Cerebral atrophy is a common radiologic manifestation of HIV dementia. To evaluate the relationship between cognitive impairment and cerebral atrophy, adjusting for age and immune status, we used standardized planimetry to measure the ventricle-brain ratio (VBR) and the bifrontal (BFR) and bicaudate (BCR) ratios, three measures of cerebral atrophy. We analyzed cranial MRIs of 23 HIV-1-seronegative controls (SN) and 116 HIV-1-infected individuals. Of the HIV-1-seropositive individuals, 37 had HIV dementia (DM group), 40 had neurologic or neuropsychological abnormalities insufficient for HIV dementia (NP+ group), and 39 were neurologically normal (NML group). We performed comparisons using analysis of covariance with correction for multiple comparisons. Both the VBR, a general measure of overall cerebral atrophy, and the BCR, a measure of atrophy in the region of the caudate nucleus, are significantly associated with dementia. The association is stronger for BCR enlargement than for VBR enlargement, suggesting that selective caudate region atrophy is associated with HIV dementia. These results indicate that overall cerebral atrophy and prominent caudate region atrophy are important radiographic features of HIV dementia.

Intrathecal synthesis of anti-HIV IgG: correlation with increasing duration of HIV-1 infection.

We determined intrathecal synthesis (ITS) of anti-HIV-1 immunoglobulin in 62 CSF samples from 51 HIV-1 seropositive homosexual men using an ELISA technique with paired serum and CSF samples diluted to a concentration of IgG of 10 micrograms/ml. All subjects were neurologically normal and none was taking zidovudine. We estimated duration of HIV-1 infection from semiannual serologic testing during the 3-year period before CSF analysis and detected ITS of anti-HIV-1 immunoglobulin in 2 of 12 (17%) of those with less than 18 months of HIV-1 seropositivity, in 3 of 21 (14%) with 19 to 36 months, and in 13 of 29 (45%) with greater than 36 months of HIV-1 seropositivity (p = 0.037). There was a trend toward an inverse relationship between level of ITS and the peripheral blood T-helper lymphocyte count. This study demonstrates that increasing ITS of anti-HIV-1 IgG is related to duration of HIV-1 infection and suggests an inverse correlation with systemic immune status. The detection of ITS of anti-HIV-1 immunoglobulin is not necessarily a marker of clinically overt neurologic involvement.

Low prevalence of neurological and neuropsychological abnormalities in otherwise healthy HIV-1-infected individuals: results from the multicenter AIDS Cohort Study.

Accurate description of the prevalence of neurological impairment in healthy individuals who are infected with human immunodeficiency virus type 1 (HIV-1) has relevance for public health policy, for employment issues, and for planning future health needs. Within the Multicenter AIDS Cohort Study, we determined the cross-sectional prevalence of neurological abnormalities in 270 HIV-1 seropositive homosexual and bisexual men in Centers for Disease Control Groups II and III, using a control group of 193 HIV-1 seronegative homosexual men. Utilizing a neurological and neuropsychological screening battery, we found no differences in the prevalence of neuropsychiatric symptoms or in neuropsychological performance. One hundred nineteen subjects with abnormalities on screening tests completed additional neuropsychological testing and had neurological examinations. The majority had normal results and the frequency of neurological abnormalities and impaired neuropsychological performance was not significantly increased among HIV-1 seropositive subjects. Most of the abnormalities could be attributed to causes other than HIV-1. One subject had mild HIV-1-related dementia, yielding a prevalence of 3.7:1,000 (95% confidence interval: 0.19-23.7:1,000). Magnetic resonance imaging demonstrated sulcal prominence and focal areas of high signal intensity in white matter in 63% of HIV-1 seropositive subjects and 48% of uninfected control subjects. Abnormalities in cerebrospinal fluid were noted in 23 (85%) of 27 HIV-1-infected individuals. Our studies indicate that the prevalence of dementia and other HIV-1-related neurological disorders is very low among healthy HIV-1 seropositive homosexual men. The confounding effects of factors such as substance abuse or preexisting medical conditions must be considered in the neurological evaluation of such patients.

Human immunodeficiency virus and the nervous system.

In conclusion, there are a number of neurological manifestations of HIV infection, affecting both the central and peripheral nervous systems. Involvement of the CNS may occur very early in the course of infection and manifest itself as an acute aseptic meningitis. HIV encephalopathy is currently the most commonly diagnosed neurologic disorder associated with HIV and may in fact occur as a direct result of HIV infection in the brain. In years to come, HIV encephalopathy may assume epidemic proportions. Thus, nurses and other health care workers will have to be well versed in the major symptoms as well as the subtleties associated with this disease. Any drugs effective in treating these neurologic disorders must be capable of crossing the blood-brain barrier. AZT is currently being evaluated in the treatment of HIV encephalopathy. Only carefully designed prospective studies will define the natural history of neurologic disorders seen with HIV infection, as well as drugs effective in their treatment.

Flow cytometric quantitation of T cell phenotypes in cerebrospinal fluid and peripheral blood of homosexual men with and without antibodies to human immunodeficiency virus, type I.

Two-color flow cytometry was used to analyze T cell subsets (total (CD3), helper-inducer (CD4), and suppressor-cytotoxic (CD8] in paired specimens of cerebrospinal fluid (CSF) and peripheral blood of 66 homosexual men, including 62 with antibodies to human immunodeficiency virus, type 1 (HIV-1). With the exception of one traumatic specimen, all of the CSF specimens, 52 of which had less than or equal to 5 lymphocytes/mm3, were evaluated fully, with the number of lymphocytes counted for each antibody ranging from 200 to 2933 (mean = 1129). Proportions of CD3, CD4, and CD8 lymphocytes in CSF were very highly correlated with the proportions of these cells in the peripheral blood (r = 0.87, 0.96, and 0.94, respectively), as was the CD4/CD8 ratio (r = 0.98). These strong correlations were present in each of seven subgroups of study subjects defined on the basis of detailed neurologic examination, neuropsychological testing, and the presence or absence of antibodies to HIV-1. In the population studied, T cell phenotypes in CSF as analyzed by two-color flow cytometry were largely determined by the corresponding proportions in the peripheral blood.

Neurological manifestations of acquired immunodeficiency syndrome.

This article provides an overview of the range of neurological manifestations that have been described in association with human immunodeficiency virus (HIV) infection. The transmission of acquired immunodeficiency syndrome (AIDS) and the precautions personnel must take when having contact with patients with AIDS are briefly reviewed. The nursing approach to the neurologically impaired victim of HIV infection is discussed.