Tennis racket sign in pulmonary tuberculosis: A case report
ABSTRACT
We report a case of ‘tennis racket sign’ in the chest radiograph of a patient with pulmonary tuberculosis (PTB). This graphic but relatively unknown sign helped us pinpoint the diagnosis. Our patient, a 24-year-old male migrant worker, presented with a five-month history of a racking cough with expectoration of blood-streaked sputum. No antecedent fever existed, but he had a concomitant loss of appetite and weight. He was seen in three different primary care facilities, and three chest radiographs were performed. These radiographs were reported as normal, with no overt evidence of pulmonary infection. Antibiotics were not useful. We believed that the history and our finding of scattered, fine crepitations in both upper zones of the lungs warranted a repeat chest radiograph. This demonstrated shadowing that we recognised as the tennis racket sign. We told the patient that the radiological shadow pointed to the diagnosis of PTB. We were able to convince the patient and his employer that the bacteriological presence of Mycobacterium tuberculosis needed to be confirmed by sputum acid-fast bacillus (AFB) smear and culture. Sputum AFB smears on three different days were positive. Because of financial constraints, the patient requested referral to the government Chest Clinic (Klinik Dada) for treatment. This case report highlights a good learning point for the primary care physician evaluating a chronic cough with a chest radiograph. A ‘normal-looking’ chest radiograph does not rule out PTB. PTB may manifest radiographic patterns we are not familiar with; the tennis racket sign is a good case in point.