Introduction Occurrence of NTM infections is increasing worldwide. Symptoms and radiological signs of NTM are similar to those of pulmonary tuberculosis (TB). When the TB diagnosis is based on AFB detection only, eventual NTM diseases can erroneously be treated as TB. The aim of this study is to identify pulmonary NTM notified as TB.

Methodology A database was constructed with NTM records during the 2008–2009 period. The records were compared with TB notifications in the SPS information system during the 2006–2010 period, using RecLink III. This software implements various file processing routines, specially the association with probabilistic record linkage.

Results During the 2008–2009 period, 6754 micobacterial cultures of pulmonary origin were performed, 4895 (72.5%) of which were identified as Mycobacterium tuberculosis Complex and 1259 (18.6%) as NTM. Among NTM patients, 449 were notified as TB, with 301 (26%) being considered as matching pairs. In 2009, the treatment outcomes revealed that 38.5% obtained TB cure and 15.4% had diagnosis change. In 2008, 56.8% obtained cure and 27.1% had diagnosis change. The most frequent NTM were Mycobacterium kansasi, Mycobacterium avium and Mycobacterium fortuitum.

Conclusions The data demonstrate that many patients notified and treated as TB had really NTM disease. Evidences support the urgent need of fast diagnosis and adequate information flow for accurate treatment.