The index of suspicion for endobronchial tuberculosis when the chest X-ray is normal.

Sir, In contrast to the absence of cough at the time of presentation with complications of endobronchial tuberculosis, 1 a chronic 'barking' or 'hacking' cough may be a notable feature of endobronchial tuberculosis, 2–4 present in 61.1% of 121 patients in one study. 2 In that study, 24.8% of the patients had radiographic evidence of loss of lung volume, 58.7% had parenchymal infiltration and 8.3% had a cavitating lesion. Furthermore, as many as 8.3% had clear lung fields. 2 Given the fact that chest radiography was normal in as many as 8.3% of the 121 patients 2 there should be a high index of suspicion for this diagnosis, despite a normal chest X-ray, when the patient gives a history of chronic 'barking' or 'hacking' cough which goes on for months and for months without any response to anti-tussive or other medications. 2–4 The index of suspicion should remain high even when the patient with hacking cough of several months duration seems to be in a low-risk category for Mycobacterium tuberculosis infection, on the basis of absence of alternative symptoms of tuberculosis, such as weight loss, fever or night sweats. 3 In the particular instance of the patient in that report, even ethnicity (Caucasian) and country of domicile (United States of America) did not mitigate against the eventual diagnosis of M. tuberculosis. 3 Delay in making the diagnosis increases the risk of transmitting M. tuberculosis infection to the patient's contacts. In one such instance the risk was high because the patient was a schoolteacher with sputum which was smear positive for acid-fast bacilli. As a result as many as 80 of her contacts subsequently required prophylaxis against M. tuberculosis. A young man with sudden ''white out'' of right hemithorax on chest radiograph.ray negative endo-bronchial tuberculosis with persistent irritating cough that resulted in unpredicted mass infection (article in Japanese: abstract in English). Response: Endobronchial tuberculosis: always a diagnostic challenge Sir, We thank Dr. Jolobe for his interest in our reported case who developed acute lung collapse due to bronchostenosis as a sequela of undiagnosed endo-bronchial tuberculosis (EBTB). 1 As Dr. Jolobe pointed out, EBTB presenting in the absence of radiologic TB lesions is often a great diagnostic challenge. The diagnosis is often delayed and some of these patients might be misdiagnosed as having asthma because of the similarity in symptomatol-ogy. 2,3 Although being well described in textbooks, 4 the so-called characteristic 'barking' …