PubMed HealthSearch

Biomedical subjects

K G Castro

Publications and source records attributed to K G Castro.

At least 19 recordsLinked to original sources

Transmission of Mycobacterium tuberculosis from tuberculosis patients with HIV infection or AIDS.

Contacts exposed to tuberculosis patients with acquired immunodeficiency syndrome (AIDS) or human immunodeficiency virus (HIV) infection were compared with contacts of HIV-negative patients for evidence of Mycobacterium tuberculosis transmission, based on a review of records of tuberculin skin tests administered during routine health department follow-up investigations in Miami/Dade County, Florida, from 1985 through 1989. After an adjusted analysis designed to balance background prevalence, tuberculin positivity was 42.0% in 2,158 contacts of HIV-negative patients compared with 28.6% and 31.3% in 363 contacts of HIV-infected patients and 732 contacts of AIDS patients, respectively. Similar results were observed in a subset of 5- to 14-year-old contacts of United States-born black or white tuberculosis patients chosen to minimize the possibility of false-negative tuberculin tests in contacts due to undiagnosed HIV infection. Analysis of contacts as sets showed a more than expected number of sets with none or all contacts infected, but this did not differ by HIV/AIDS group. In this study, tuberculosis patients with AIDS or HIV infection were less infectious to their contacts and, in this community, exposed fewer contacts than HIV-negative tuberculosis patients.

AIDS-Related Opportunistic Infections

Transmission of multidrug-resistant Mycobacterium tuberculosis during a long airplane flight.

BACKGROUND: In April 1994, a passenger with infectious multi-drug resistant tuberculosis traveled on commercial-airline flights from Honolulu to Chicago and from Chicago to Baltimore and returned one month later. We sought to determine whether she had infected any of her contacts on this extensive trip. METHODS: Passengers and crew were identified from airline records and were notified of their exposure, asked to complete a questionnaire, and screened by tuberculin skin tests. RESULTS: Of the 925 people on the airplanes, 802 (86.7 percent) responded. All 11 contacts with positive tuberculin skin tests who were on the April flights and 2 of 3 contacts with positive tests who were on the Baltimore-to-Chicago flight in May had other risk factors for tuberculosis. More contacts on the final, 8.75-hour flight from Chicago to Honolulu had positive skin tests than those on the other three flights (6 percent, as compared with 2.3, 3.8, and 2.8 percent). Of 15 contacts with positive tests on the May flight from Chicago to Honolulu, 6 (4 with skin-test conversion) had no other risk factors; all 6 had sat in the same section of the plane as the index patient (P=0.001). Passengers seated within two rows of the index patient were more likely to have positive tuberculin skin tests than those in the rest of the section (4 of 13, or 30.8 percent, vs. 2 of 55, or 3.6 percent; rate ratio, 8.5; 95 percent confidence interval, 1.7 to 41.3; P=0.01). CONCLUSIONS: The transmission of Mycobacterium tuberculosis that we describe aboard a commercial aircraft involved a highly infectious passenger, a long flight, and close proximity of contacts to the index patient.

Adult

Tuberculosis surveillance in the United States: case definitions used by state health departments.

Health departments in all 53 reporting areas in the United States were asked to submit the case definition they used for tuberculosis surveillance. Sixteen areas used the 1990 case definition; two areas sent 1977 guidelines; and 34 areas sent other definitions. Case reports sent to the Centers for Disease Control and Prevention (CDC) in 1992 were analyzed; 4% of cases did not meet the 1990 definition. Tuberculosis case reporting criteria are not uniformly applied in the United States. CDC, in collaboration with state and local health officials, is evaluating the current definition and will implement uniform national criteria for tuberculosis surveillance.

Adolescent

How important is race/ethnicity as an indicator of risk for specific AIDS-defining conditions?

In order to examine differences in the prevalence of AIDS-defining conditions by race/ethnicity, we analyzed U.S. surveillance data for 203,470 adolescents and adults diagnosed with AIDS from 1988 through 1992. A number of AIDS-indicator conditions were more common among certain racial/ethnic groups. The prevalence of extrapulmonary tuberculosis was higher among blacks, Hispanics, Asians/Pacific Islanders, and American Indians/Alaskan Natives than among whites. The prevalence of isosporiasis and toxoplasmosis was higher among Hispanics than among blacks or whites. Furthermore, the likelihood of being diagnosed with extrapulmonary tuberculosis (TB), toxoplasmosis, or isosporiasis was generally higher among foreign-born than among U.S.-born persons of all racial/ethnic groups. The prevalence of all malignancies was higher among whites than among blacks or Hispanics. However, the magnitude of prevalence differences by race/ethnicity was reduced when we controlled for other demographic and exposure risk categories. Although race/ethnicity was significantly associated with the prevalence of a number of conditions, the relative frequency and patterns of AIDS-indicator conditions in different populations are probably most influenced by differences in (1) underlying prevalence or exposure to various etiologic agents causing these conditions, (2) diagnosis and reporting of conditions, and (3) access to care and therapy for HIV-related conditions.

Acquired Immunodeficiency Syndrome

Tuberculosis as an opportunistic disease in persons infected with human immunodeficiency virus.

Tuberculosis, a bacterial disease caused by the Mycobacterium tuberculosis complex, is becoming an increasingly common opportunistic disease in persons infected with the human immunodeficiency virus (HIV). M. tuberculosis is transmitted from person-to-person by airborne droplet nuclei. Persons who are exposed to these droplet nuclei in poorly ventilated environments are at risk of becoming infected with M. tuberculosis. HIV infection is probably the most significant risk factor associated with progression from latent M. tuberculosis infection to active disease. Thus, HIV-infected persons should avoid exposure to M. tuberculosis, they should be screened for evidence of latent infection with the tuberculin skin test, and they should be offered preventive therapy. Because many severely immunosuppressed anergic HIV-infected persons have been found to have an increased risk of developing active tuberculosis, decisions to use preventive therapy should be individualized on the basis of the local prevalence of tuberculosis and drug-resistance patterns. Persons with active tuberculosis should receive at least 6 months of treatment with recommended regimens, preferably with directly observed therapy, to ensure adequate bacteriologic response, completion of therapy, and cure. Chronic suppressive therapy after completion of therapy is currently not recommended.

AIDS-Related Opportunistic Infections

The changing face of tuberculosis.

Tuberculosis (TB) remains an important public health problem worldwide, resulting in a estimated 8 to 10 million new cases and 2 to 3 million deaths each year. Between 1953 and 1985, the number of TB cases in the US declined by an average of 6% per year. However, since 1985, TB has been increasing in the US. Approximately 64,000 additional cases of the disease have been reported beyond the number expected had the rate of decline observed from 1980 to 1984 continued from 1985 through 1993. Increases in the number of TB cases have been significant in racial and ethnic minorities, in persons born outside the US, and in children less than 15 years of age. Infection with the human immunodeficiency virus (HIV) has also been recognized as a major risk factor for the development of active TB in persons with latent Mycobacterium tuberculosis infection. The unusual radiographic findings and the increased likelihood of extrapulmonary TB in HIV-infected persons make diagnosis of the disease problematic. Lastly, concomitant with the resurgence of TB has been the emergence of drug resistance. All of these factors make successful control of TB in the US difficult.

AIDS-Related Opportunistic Infections

Women at a sexually transmitted disease clinic who reported same-sex contact: their HIV seroprevalence and risk behaviors.

OBJECTIVES: This study compares characteristics, behaviors, and human immunodeficiency virus (HIV) infection in women who reported same-sex contact and women who had sex only with men. METHODS: Participants were patients attending a New York City sexually transmitted disease clinic. Structured questionnaires were administered by interviewers. RESULTS: Overall, 9% (135/1518) of women reported same-sex contact; among these, 93% also reported contact with men. Women reporting same-sex contact were more likely than exclusively heterosexual women to be HIV seropositive (17% vs 11%; odds ratio [OR] = 1.7, 95% confidence interval [CI] = 1.0, 2.6), to exchange sex for money/drugs (48% vs 12%, OR = 6.7, 95% CI = 4.6, 9.8), to inject drugs (31% vs 7%, OR = 6.3, 95% CI = 4.1, 9.5), and to use crack cocaine (37% vs 15%, OR = 3.3, 95% CI = 2.2, 4.8). HIV in women reporting same-sex contact was associated with history of syphilis (OR = 8.8), sex for crack (OR = 5.7), and injection drug use (OR = 4.5). CONCLUSIONS: In this study, women who reported same-sex contact were predominantly bisexual. They had more HIV risk behaviors and were more often HIV seropositive than women who had sex only with men. Among these bisexual women, heterosexual contact and injection drug use were the most likely sources of HIV. There was no evidence of female-to-female transmission.

Adult

Effect of HIV infection and tuberculosis on hospitalizations and cost of care for young adults in the United States, 1985 to 1990.

OBJECTIVE: To evaluate the effect of human immunodeficiency virus (HIV) infection and tuberculosis on hospitalizations and the cost of care. DESIGN: National Hospital Discharge Survey, a nationally representative survey of discharges from U.S. nonfederal short-stay hospitals, and statewide billing information. PATIENTS: Patients 15 to 44 years of age with a listed diagnosis of HIV infection (n = 418,200) or active tuberculosis (n = 77,700) during 1985-1990. RESULTS: During 1985-1990, hospitalizations related to HIV infection increased sixfold, from 18 to 102 per 100,000 persons; during 1988-1990, hospitalizations related to tuberculosis increased twofold, from 8 to 16 per 100,000 persons. The prevalence of tuberculosis among HIV-infected patients increased from 2.4% in 1985-1988 to 5.1% in 1989-1990 (P = 0.003). The prevalence of HIV infection among patients with tuberculosis increased from 11% in 1985-1988 to 28% in 1989 to 39% in 1990 (P < 0.001). Infection with HIV was more prevalent among patients with extrapulmonary tuberculosis (31%) than among those with pulmonary tuberculosis (18%) (P = 0.01). An increase in the duration of hospital stay was associated with both tuberculosis and HIV infection. From 1985 to 1990, inpatient care costs increased 7.7-fold and 3.2-fold for HIV and tuberculosis hospitalizations, respectively. During this period, HIV and tuberculosis hospitalizations resulted in 5,793,000 and 1,107,900 days of care, respectively, with an estimated direct cost of $5.7 to $7.4 billion and $0.89 to $1.07 billion, respectively. Estimated national costs of inpatient care for HIV infection or tuberculosis or both totaled $6.4 to $8.1 billion, 5% of which was for patients with both HIV infection and tuberculosis. CONCLUSIONS: This is the first study to use a nationally representative sample of hospitals, combined with cost data, to estimate hospitalizations and their costs for HIV and tuberculosis care. Our findings suggest that the convergence of the HIV and tuberculosis epidemics has had an increasing effect on morbidity and the cost of care among young adults in the United States. The increasing prevalence of comorbidity of HIV infection and tuberculosis in inpatients underscores the need for strict infection control of tuberculosis on the part of hospitals, increased attention to prevention, and early identification and treatment of HIV infection, and tuberculosis to reduce morbidity, hospitalizations, and the cost of care.

Adolescent

Transmission of Mycobacterium tuberculosis associated with air travel.

OBJECTIVE: To investigate potential transmission of Mycobacterium tuberculosis in aircraft from a crew member with tuberculosis. DESIGN: Retrospective cohort study and survey. SETTING: A large US airline carrier. PARTICIPANTS: A total of 212 crew members and 59 passengers who were exposed to a crew member with tuberculosis during a potentially infectious period (May through October 1992). Comparison volunteer sample of 247 unexposed crew members. MAIN OUTCOME MEASURES: Positive tuberculin skin test (TST) result or tuberculosis. RESULTS: Rates of positive TST results were higher among foreign-born persons in all study groups. Among US-born comparisons and contacts, rates of positive TST results did not differ between comparisons and contacts exposed from May through July (5.3% vs 5.9%, respectively). However, contacts exposed from August through October had significantly higher rates of positive TST results than did contacts exposed from May through July (30% vs 5.8%, respectively; P < .001); two had documented TST conversions between September 1992 and February 1993. The risk of infection increased with increasing hours of exposure to the index case. Four (6.7%) of 59 frequent flyers were TST-positive; all flew in October. CONCLUSIONS: Data support the conclusion that M tuberculosis was transmitted from an infectious crew member to other crew members on an aircraft. Because of the clustering of TST-positive frequent flyers in October when the index patient was most infectious, transmission of M tuberculosis to passengers cannot be excluded.

Air Pollution, Indoor

Purified protein derivative tuberculin and delayed-type hypersensitivity skin testing in migrant farm workers at risk for tuberculosis and HIV coinfection.

OBJECTIVE: To assess the joint use of purified protein derivative (PPD) and delayed-type hypersensitivity (DTH) antigens in screening individuals of unknown HIV serostatus for tuberculosis (TB) preventive therapy eligibility. DESIGN: Population-based survey. METHODS: A group of migrant farm workers were screened for HIV and skin-tested with PPD, tetanus toxoid (TET), Candida albicans (CAN) and mumps (MUM) antigens by the Mantoux method. Anergy was defined as a < or = 2 mm reaction to all four antigens. Eligibility for preventive therapy was defined as a reaction of > or = 5 mm to PPD among HIV-seropositive individuals, > or = 10 mm among HIV-seronegatives, or anergy. RESULTS: A total of 253 out of 271 individuals had sufficient data for analysis. Of these, 15 (5%) were HIV-seropositive; 183 (75%), 175 (72%) and 157 (65%) reacted to TET, CAN, and MUM, respectively, and 113 (47%) were eligible for preventive therapy [108 (44%) PPD-positive, five (2%) anergic]. Use of PPD alone was 95% sensitive for detecting preventive therapy eligibility; PPD plus one DTH antigen was more sensitive (99%) but less specific (range, 69-85%); PPD plus two DTH antigens was most specific (CAN + MUM, 84%; TET + MUM, 93%; and TET + CAN, 100%). CONCLUSIONS: In this population with 5% HIV seroprevalence, testing for anergy did not significantly increase the detection of preventive therapy eligibility. The use of two DTH antigens is very sensitive and specific. These results support the recommendation of joint PPD and anergy testing for the screening of HIV-seropositive individuals. Our data also suggest, however, that for individuals whose HIV serostatus is unknown, anergy testing should be considered as a screening tool only if the prevalence of anergy is expected to exceed the prevalence of PPD positivity.

Adolescent

HIV infection and AIDS in Latin America. Epidemiologic features and clinical manifestations.

This article updates the epidemiologic situation of HIV and AIDS infection and summarizes the most common clinical manifestations in Latin American countries. As of December 1992, a total of 59,723 AIDS cases had been reported to the Pan American Health Organization from Mexico, Central America, South America, and the Latin Caribbean. The number of deaths totaled 24,500, or 41% of the reported cases. HIV transmission patterns and clinical manifestations vary by region. The most common opportunistic illnesses in Latin America and their symptoms, including gastrointestinal, pulmonary, and dermatologic complications are discussed.

Acquired Immunodeficiency Syndrome