Objectives
To describe the early symptoms of pulmonary tuberculosis (TB) when the chest radiograph
(CXR) is normal.
Setting
Centralized, provincial TB control program.
Subjects
Twenty-five patients with culture-positive pulmonary TB and a normal CXR were identified
from a review of 518 consecutive patients with culture-positive pulmonary TB in the
province of Saskatchewan from January 1, 1988 to March 31, 1997. Patients with abnormal
CXRs at the time of diagnosis were excluded from the analysis.
Results
Twenty-three of the 25 patients (92%) were symptomatic at the time of diagnosis, with
cough/sputum (76%) being reported most commonly. Eleven patients were identified because
of contact tracing from cases of infectious pulmonary TB, while the other 14 patients
were identified because of an investigation of symptoms. Twenty-four patients (96%)
exhibited one or more symptoms of cough for > 1 month, fever for > 1 week, or skin-test
conversion after contact with infectious TB. The sputum smear of only one patient
was positive. Two patients were pregnant at the time of diagnosis, one patient was
HIV-positive, and one patient demonstrated isoniazid-resistant organisms on sensitivity
testing. Five patients were diagnosed as having primary TB associated with Mantoux
skin-test conversion. The incidence of culture-positive pulmonary TB with a normal
chest radiograph was < 1% in the period from 1988 to 1989 and steadily increased to
10% in the period from 1996 to 1997.
Conclusions
Culture-positive pulmonary TB with a normal CXR is not uncommon, and the incidence
of this presentation is increasing. Patients with this presentation of TB are typically
symptomatic and/or are detected by contact tracing to infectious cases of pulmonary
TB. The results suggest that patients presenting with a cough for > 1 month, with
a fever for > 1 week, or with documented skin-test conversion < 2 years after known
exposure to infectious TB should have sputum submitted for a
Mycobacterium tuberculosis smear and culture despite a normal CXR.
Key words
Abbreviations:
CXR ( chestradiograph), TB ( tuberculosis)To read this article in full you will need to make a payment
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Article Info
Publication History
Accepted:
August 18,
1998
Received:
February 18,
1998
Identification
Copyright
© 1999 The American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.
