Rates and risk factors for discontinuation of rifampicin

All patients with culture-confirmed, rifampin-susceptible Mycobacterium tuberculosis diagnosed during a 20-month period in New York City, who were started on a rifampin-containing regimen and received > or =60 days of treatment.

To identify rates of and reasons for rifampin discontinuation.

Retrospective case-control study using surveillance data and medical record reviews. Discontinuation due to thrombocytopenia, creatinine >2.0 mg/dl, bilirubin >2.0 mg/dl or severe reactions (generalized rash, persistent drug fever, or severe interference with methadone metabolism) were defined as appropriate for discontinuation of rifampin. All other reactions were classified as inappropriate.

Of 3,520 patients, rifampin was discontinued in 68 (1.9%); of these, 57% had rifampin discontinued unnecessarily. Treatment by an inexperienced provider (adjusted odds ratio [ORadj] 4.0; 95% confidence interval [CI] 1.9-8.5), race (ORadj 3.1; 95%CI 1.4-6.9), history of previous treatment (ORadj 4.8; 95%CI 1.9-12.5), and history of methadone drug treatment (ORadj 12.6; 95%CI 5.3-29.9) were all associated with inappropriate rifampin discontinuation.

True intolerance was rare, even among those patients infected with the human immunodeficiency virus. Most patients with minor reactions can successfully complete treatment with rifampin, particularly if managed by a physician experienced in the treatment of tuberculosis.