False-positive tuberculin skin tests in a state prison system.

OBJECTIVE: To assess the existence and extent of false-positive tuberculin skin test (TST) results in a regularly tested population subsequent to switching to a different skin testing product. METHOD: Over 9300 state prison inmates were tuberculin skin tested as part of a routine annual testing program. A shortage of Tubersol caused the prison system to purchase and test with Aplisol. Prison health services staff reported an apparent increase in skin test positivity using Aplisol compared to Tubersol. Record reviews were conducted in 34 prisons where inmates read as positive (> or = 5 mm) were retested with Tubersol. RESULTS: Among 368 inmates recorded as positive (> or = 5 mm) with Aplisol who were retested with Tubersol, 150 (40.8%) were read as negative (0-4 mm). CONCLUSION: The tuberculin skin test is a valuable tool in evaluating patients for TB infection. However, variations in planting and reading the test, and in the consistency between lots and manufacturers, can contribute to errors in determining an individual's infection status. The entire clinical and epidemiological picture for each patient must always be evaluated using the TST as a tool, and not an indisputable answer.

Tuberculosis control in the New York State Department of Correctional Services: a case management approach.

In the New York State Department of Correctional Services (DOCS), the incidence of tuberculosis (TB) increased from 43 per 100,000 persons in 1985 to 225 per 100,000 in 1991. To combat this increase in cases, the NYSDOCS enhanced its collaborative efforts with the New York State Department of Health and the Division of Parole, developing a comprehensive TB control program. This control program focuses on prevention and containment of disease. Policies and directives were developed on the basis of epidemiologic principles, which include surveillance and detection. To assist the NYSDOCS in the implementation of the TB control program statewide, a team of infection control nurses was established in July 1992. A case management approach was used, and TB registry was developed. Each case of active and suspected TB was monitored closely to ensure appropriate containment, identification, and treatment measures. Transfers within the state system also were monitored to promote continuity. Discharge planning coordination with the DOCS, Division of Parole, and Department of Health is facilitated by the infection control nurses. Directly observed preventive therapy and directly observed therapy is used for inmates. Staff and inmates are provided education that addresses mandatory annual skin testing, diagnosis, containment procedures, disease process, and treatment modes. Implementation of this comprehensive TB control program in NYSDOCS has strongly contributed to reducing the incidence of TB. In 1997, the incidence rate was 61 TB cases per 100,000 persons--a 73% decrease since 1991. The conversion rate for staff and inmates has steadily declined since 1993. No new outbreaks have occurred in NYSDOCS since 1993.