We previously described characteristics associated with pulmonary disease in patients with NTM isolated from respiratory specimens.1 The present study was intended to determine what characteristics may influence physicians to initiate treatment in patients with NTM pulmonary disease.
We reviewed the records of the 126 adults in our institution with at least one respiratory culture positive for NTM between January 1998 and June 2002. We identified 27 HIV-negative patients who met criteria for pulmonary NTM disease based on the 1997 ATS statement.2 Statistical analysis was performed using Fisher’s exact test.
Of the 27 patients, 19 (70%) were offered treatment. Multiple positive sputum AFB smears were associated with a greater likelihood of being offered treatment. Infiltrate without cavity or nodule was associated with decision not to treat. There was a nonsignificant trend toward treatment of cavitary disease. (Table 1Characteristics of Patients With NTM Pulmonary Disease Offered Treatment (n=27)Offered Treatment (n=19)Not Offered Treatment (n=8)p Value2 or more AFB + smears1210.03Infiltrate alone560.03Cavity1010.09Nodules831.0)CONCLUSIONS: The 1997 ATS statement suggests criteria to diagnose NTM pulmonary disease. We found that only 70% of patients who met the ATS criteria were offered treatment.Cavitary disease and high microbial burden appear to influence physicians to treat whereas patients with infiltrates alone are often not offered treatment despite meeting ATS criteria for disease.
Further studies are needed to determine the outcomes of patients with NTM pulmonary disease who are not treated. If these patients fare well, it may indicate that the presence of infiltrate without nodules or cavities should not be used in making the diagnosis. It also might indicate that zero or one positive smear may not indicate the need for treatment even with three positive cultures.
G. Tatem, None.