Monitoring preventive therapy patients for liver disease as well as compliance.

An apparently increasing incidence of isoniazid-associated hepatitis concurrent with interest in the problem has led to the universal teaching that patients on isoniazid preventive therapy must be carefully monitored for liver disease. This teaching has been reinforced and endorsed in a recent report of the tuberculosis advisory committee and special consultants to the director of the Center for Disease Control; this report, in turn, led to an American Thoracic Society statement concluding that the use of isoniazid with appropriate safeguards must be based on a comparison of the benefit of preventive therapy with the risk of hepatic injury and, therefore, should be used when necessary, under careful control and follow-up. In New York City, with increasing use of the tuberculin skin test leading to increased numbers of patients receiving this treatment in nurse-operated clinics, a new control form and protocol were designed. These insure that all individuals on preventive therapy are carefully monitored for liver disease as well as compliance in taking the drug. This system also insures the safeguards alluded to, as well as increasing concern and awareness among the health professionals in prescribing the treatment.