Lack of evidence to support policy development for management of contacts of multidrug-resistant tuberculosis patients: two systematic reviews

BACKGROUND: Existing international guidelines provide different recommendations for the management of contacts of multidrug-resistant tuberculosis (MDR-TB) patients. OBJECTIVE: To conduct two systematic reviews with the aim of identifying chemoprophylactic approaches that are effective in contacts of MDR-TB patients to assist in policy making. DESIGN: We systematically searched the Medline, Embase, Central, LILACS, TRIP and BIOSIS Preview databases for studies on the effectiveness of anti-tuberculosis drugs in preventing active TB in persons at risk of developing MDR-TB. This was done as an update of a systematic review from 2006 using the same methodology. In addition, we searched for studies including persons at risk of developing TB after exposure to non-MDR-TB patients who were treated with anti-tuberculosis drugs other than isoniazid or rifampicin. RESULTS: Of 1195 references assessed in the update, one additional study could be included. As the initial review included two studies, the total number of included studies equals three. One study reported no contacts who developed TB, whether or not they received prophylaxis. The other two studies showed non-significant risk differences of 4% (95%CI -3 to 12), and 5% (95%CI -2 to 11), both in favour of chemoprophylaxis. For the additional review, 2480 references were assessed, but none could be included. CONCLUSION: The attention given to MDR-TB in recent years has not resulted in publications on preventive treatment for contacts of MDR-TB patients. The available evidence is not sufficient to support or reject preventive treatment. Furthermore, the combined available evidence is of very low quality.