Evaluation of infection control parameters according to the 1994 Centers for Disease Control and Prevention Tuberculosis guidelines: a 2-year experience.

BACKGROUND

Because of classification as a high-risk institution for potential Mycobacterium tuberculosis exposure and an employee purified protein derivative conversion rate of 2.7%, a large university-affiliated county hospital enhanced administrative and engineering controls, as recommended by its tuberculosis task force in early 1994.

METHODS

For 1994 and 1995 the medical records of all patients with culture-confirmed M. tuberculosis were reviewed according to the 1994 Centers for Disease Control and Prevention guidelines for case surveillance and risk assessment (infection control parameters). The chi 2-test was used to compare 1994 and 1995 infection control parameters for statistical significance (p < or = 0.05).

RESULTS

In 1994 and 1995 there were 253 patients with tuberculosis, 85% of whom (214/253) had pulmonary-site tuberculosis. The "representative" patient with pulmonary tuberculosis was profiled, along with institution-specific surveillance data on diagnostics, medication regimens, and airborne isolation practices. Between 1994 and 1995 there was a trend toward increased numbers of homeless patients with tuberculosis, from 8.2% to 17% (p = 0.07). Decreases in the numbers of HIV seropositive patients with tuberculosis from 35% in 1994 to 24% in 1995 (p = 0.2) and of jailed patients with tuberculosis from 9.8% to 5% (p = 0.5) were not significant. Drug-resistance patterns increased from 13% to 24%, with borderline significance (p = 0.06). The employee purified protein derivative testing compliance rate increased from 49% in 1994 to 74% in 1995, with the purified protein derivative conversion rate also increasing from 2.7% to 3.5%.

CONCLUSION

The infection control parameter data were beneficial in identification of institution-specific risk factors for our population with tuberculosis. Although labor-intensive, the annual tuberculosis reports supported requests for administrative and engineering controls; however, efficacy of the 1994 tuberculosis control plan was difficult to assess from purified protein derivative conversion rates alone, because the testing compliance rate also increased.