Faculty Bibliography

SETTING: A large public hospital in New York City. OBJECTIVE: To determine the prevalence of tuberculosis infection and disease in a cohort of indigent persons in New York. DESIGN: Persons seeking social services at any of five community-based organizations in New York City were screened for tuberculosis infection using tuberculin skin testing and a symptom questionnaire. Skin test or symptom positive persons were referred to the Bellevue Hospital Chest Clinic for a chest radiograph and medical evaluation. After this evaluation, patients were classified into a diagnostic category (e.g. tuberculosis infection, tuberculosis disease, no evidence of tuberculosis infection or disease). RESULTS: Of 651 persons screened, 591 (91%) completed the initial evaluation. The tuberculosis infection prevalence for the entire cohort was 41% (95% Confidence Interval [CI], 37% to 45%). Risk factors for infection included residence in a congregate setting, drug use, and birth outside the United States. Human immunodeficiency virus (HIV) infection was not a risk factor for infection. Eleven cases of active tuberculosis were also detected (disease prevalence of 1.7%, 95% CI, 0.85% to 3%). Most of the patients with active tuberculosis had documented HIV infection or clear risk factors for HIV. CONCLUSION: We conclude that tuberculosis infection and disease remain common in populations characterized by poor housing conditions, drug use, and HIV infection. Linking a major medical provider with community-based organizations is an effective means to provide highly targeted screening services to a population at serious risk for disease acquisition and transmission

OBJECTIVE:To compare literature-based estimates of the cost-effectiveness ratios of strategies for secondary prophylaxis of Pneumocystis carinii pneumonia (PCP) in AIDS patients with estimates obtained using data from a recent comparative clinical trial. DESIGN/METHODS:A decision-analytic Markov model with data on drug efficacy and toxicity from both the medical literature and a national randomized clinical trial. Drug costs were from average wholesale prices. Discounted life expectancy, total direct medical costs, and cost-effectiveness were projected in dollars per year of life saved (YLS). SETTING/METHODS:Hypothetical for the literature-based model, then the clinical trial results from the multicenter AIDS Clinical Trials Group (ACTG Protocol 021). PATIENT POPULATION/METHODS:Patients with AIDS and a prior episode of PCP. INTERVENTIONS/METHODS:Strategies included no prophylaxis, TMP-SMX (160/800 mg) daily, or aerosolized pentamidine (300 mg) monthly. Patients experiencing major toxic reactions to either medication would cross over to the other agent. MAIN RESULTS/RESULTS:In the literature-based model no prophylaxis was associated with a projected life expectancy of 1.430 years, and total direct cost of $42,080. TMP-SMX increased life expectancy to 2.051 years and cost to $42,300; for aerosolized pentamidine life expectancy was 2.066 years and cost $43,960. TMP-SMX had an incremental cost-effectiveness ratio of $350 per YLS compared with no prophylaxis; the incremental ratio for aerosolized pentamidine was $2,950 per YLS when compared with no prophylaxis, but rose to $110,880 per YLS compared with TMP-SMX. When data from ACTG clinical trial 021 were utilized in the model, the incremental cost-effectiveness ratio for TMP-SMX compared with no prophylaxis was $720 per YLS; aerosolized pentamidine was not cost-effective, and was "dominated" by TMP-SMX because it was associated with higher costs and shorter life expectancy. CONCLUSIONS:Literature-based cost-effectiveness models are useful in developing health policy before clinical trials are completed. Clinical trial results, when available, can be used to validate and revise these models. For secondary PCP prophylaxis in AIDS patients, TMP-SMX is substantially more cost-effective than aerosolized pentamidine.

Infants are reported to be devoid of memory T cells at birth but acquired them with time. A cross-sectional study of peripheral blood mononuclear cells from HIV-infected and uninfected infants and children that bear the CD4R0 antigen was undertaken to describe the development of memory T cells. Linear regression lines derived from the data revealed increasing percentages of memory CD4 and CD8 cells in the uninfected children. Memory CD4 cells in the infected children were detected at a frequency equal to or greater than that seen in uninfected children until 6 months of age but subsequently declined with age. In contrast, memory CD8 cells were found to be significantly increased in HIV-infected children early in life with a rate of increase similar to that seen in the uninfected population. This increase in memory CD8 cells may facilitate the early diagnosis of HIV infection

Cryptosporidial infection causes severe diarrheal disease in patients with AIDS. Fourteen patients with AIDS and symptomatic cryptosporidiosis were treated with a specific bovine dialyzable leukocyte extract (immune DLE) prepared from lymph node lymphocytes of calves immunized with cryptosporidia or a nonspecific (nonimmune) DLE prepared from nonimmunized calves. Six of 7 patients given immune DLE gained weight and had a decrease in bowel movement frequency, with eradication of oocysts from stool in 5 patients. Six of 7 patients given nonimmune DLE showed no decrease in bowel movement and 4, no clearing of oocytes from stool; 5 continued to lose weight. Subsequently, 5 of these 7 were treated with immune DLE; 4 had a decrease in bowel movement frequency and significant weight gain, with eradication of oocytes from stool in 2 patients. Immune DLE produces sustained symptomatic improvement in patients with AIDS and active cryptosporidiosis, but lack of an appropriate cryptosporidial antigen allows only postulation that an augmentation of cellular immunity to Cryptosporidium parvum induced by immune DLE resulted in the microbiologic and clinical improvement observed

To limit nosocomial spread of respiratory syncytial virus (RSV) infection, a longitudinal intervention trial was instituted. Nasal secretions or washes were screened for RSV antigen by enzyme-linked immunosorbent assay, and patients were assigned to an RSV-infected or an RSV-uninfected cohort. The baseline (preintervention) rate of 7.17 nosocomial cases of RSV per 1000 patient-days of care was used for comparison. Despite continued infections in the community after screening was initiated, there were no cases of RSV infection in 1880 patient-days of care for 3 months (p = 0.039). During the fourth month, an RSV-infected child was erroneously assigned to the RSV-uninfected cohort, and three nosocomial cases occurred--5.33/1000 patient-days of care (p = 0.286). Overall, there were three nosocomial RSV infections in 2443 patient-days of care in the 1987 season after screening was introduced--1.23/1000 patient-days of care (p = 0.026). In the subsequent RSV season, there was one nosocomial case--0.461/1000 patient-days of care for 3 months (p = 0.0074). During the same period, nosocomial cases of RSV were observed in the pediatric and neonatal intensive care units, where assignment to a cohort was not possible. We conclude that entry into a cohort at the time of admission, on the basis of prospective RSV screening by enzyme-linked immunosorbent assay, effectively reduces nosocomial transmission of RSV

Although listeriosis is an uncommon infection in patients with human immunodeficiency virus (HIV) infection, the frequency of listeriosis in New York City has increased because of the increase in the number of HIV-infected patients. The medical records of 30 patients admitted to three medical centers in New York City from 1981 to 1988 with infections due to Listeria monocytogenes were reviewed. Six patients had AIDS, one was seropositive and asymptomatic, and four had risk factors for HIV infection. While the annual number of cases of listeriosis in patients without risk factors for HIV infection was constant, 9 of the 11 patients with AIDS or with risk factors for HIV infection presented with listeriosis between 1985 and 1988, the last half of the survey period. These patients were male homosexuals or intravenous drug abusers, and all but one were black or Hispanic. Manifestations of listeriosis in patients with AIDS or with risk factors for HIV infection included bacteremia without apparent source in seven, meningitis in three, and endocarditis in one, syndromes that were similar to those in patients without risk factors for HIV infection. Ten of 11 patients were treated with penicillin or ampicillin, and 7 were also given an aminoglycoside. All patients responded well to therapy and no relapses were observed. Physicians should include antibiotics effective against L. monocytogenes when treating AIDS patients with meningitis of unknown origin and consider the diagnosis of listeriosis in patients with sepsis of unknown origin