Over diagnosis of smear negative pulmonary tuberculosis in patients with allergic bronchopulmonary aspergillosis: A study from high tuberculosis burden country

<b>Objective:</b> Allergic Bronchopulmonary Aspergillosis (ABPA) patients usually have chronic persistent symptoms if remain undiagnosed. In country like Pakistan where Tuberculosis (TB) is endemic these patients misdiagnosed as smear negative TB and received antituberculous treatment (ATT) empirically. The aim of the study is to determine the frequency such patients with ABPA. <b>Methods:</b> A retrospective study was conducted on ABPA patients presented at outpatient pulmonary clinic of Aga Khan University Hospital, Karachi, Pakistan from January 2017 to December 2018. All patients were rule out for active TB by AFB smear c/s and Xpert MTB/Rif. <b>Result:</b> A total 167 patients of ABPA were included,91(54.5%) were female (mean age 41.9 ± 13.0 years) and 71(42.5%) patients had recieved ATT in past. Out of these 71 patients, 63(88.7%) patients had received empiric ATT as smear –ve TB. Among 63 patients, 52 (82.5%) patient had received ATT once, 8(12.6%) twice and 3(4.7%) patients had received ATT thrice. Only 7(4.2%) patients were aware of ABPA before presenting to clinic. Out of 167, 27(16.16%) patients developed long term complications and 17(62.96%) patients were in smear –ve TB treatment group. Recurrent hemoptysis was developed in 7, chronic respiratory failure in 6, chronic pulmonary aspergillosis in 5 and corpulmonale in 5 patients. <b>Conclusion:</b> Patient with ABPA frequently received empiric ATT as smear –ve TB in high TB burden country. This results in over diagnosis of TB and unnecessary use of global resource. Moreover dealy in diagnosis leads to long term complications. Awareness regarding ABPA is required in high TB burden countries.