Primary Pulmonary Tuberculosis: An Uncommon Presentation

Figure 1

Figure 2

1. Cough, fever, and malaiseA 53-year-old man has hadmalaise, intermittent cough, and occasionalfever and night sweats for 2weeks. He has also lost some weightduring this time but denies hemoptysisand sputum production; he hasnot traveled abroad recently. His onlysignificant medical condition is hypertension,which is well controlled withmedication.

Temperature is 37.2^oC (99^oF);heart rate, 88 beats per minute; respirationrate, 18 breaths per minute; andblood pressure, 135/84 mm Hg. Resultsof cardiac, abdominal, and neurologicexaminations are normal. Breathsounds are decreased in the middleand lower lobes of the right lung.

You order frontal and lateral uprightradiographs of the chest. Whatabnormalities are evident on thesefilms, and how will you proceed todetermine their cause?

1. Cough, fever, and malaise:

Thefrontal (

A

) and lateral (

B

) radiographsreveal ill-defined opacities inthe middle and upper lobes of theright lung (

A and B, white arrows

)and thickening in the right apex (

A,yellow arrow

).You order a CT scan of thechest. An axial image at the level ofthe middle third of the left ventricleshows an opacity in the superior segmentof the right lower lobe (

C,arrow

). An axial image at the level ofthe pulmonary outflow tract shows ill-defined opacities inboth the superior segment of the right lower lobe and theright middle lobe (

D, arrows

).Soft tissue windows from just below the level of theaortic arch reveal a lymph node with a low-density center(a necrotic lymph node) posterior to the trachea, slightlyabove the carina (

E, arrow

). Soft tissue windows at thelevel of the thoracic inlet confirm the pleural thickening inthe right apex (

F, arrow

).Based on the findings of a necrotic lymph node andmultifocal air-space opacity, tuberculosis and fungal diseaseare included in the differential diagnosis. Sputumsamples are positive for

Mycobacterium tuberculosis, andprimary pulmonary tuberculosis

is diagnosed.A presentation such as this man's typically occurs inchildren, but it has also been seen in previously unexposedadults. The vast majority of patients have no symptoms.Radiographic features of primary pulmonary tuberculosisinclude:

• Areas of ill-defined air-space opacity, as seen here.
• Cavitation (in a minority of patients).
• Pleural effusions, which more commonly occur in adults.

On CT, the adenopathy associated with tuberculosisappears as a low-density center of necrosis, as in thisman.

Outcome of this case.

The patient received multidrugtherapy. At 6-month follow-up, he was doing well andsputum samples were negative.

2. Right-sided chest pain after a car accident

A 32-year-old man is brought to the emergency department after anothervehicle hit the right side of the car in which he was a passenger. He hassignificant pain, particularly on the right side of his chest. Medical history isnoncontributory.This man is in moderate respiratory distress, but his condition is stable;his blood pressure, heart rate, and oxygen saturation have been normal sincethe accident. Results of a neurologic examination are normal; there are novisible injuries to the head or neck. Heart, abdomen, and extremities are alsonormal. A large hematoma is present on the right side of the chest. Palpationof the right side of the chest reveals crepitus and significant pain in the posterioraspect. Breath sounds are significantly reduced at the right lung base. Theright posterior hemithorax exhibits paradoxical mobility compared with theother segments of the chest.A supine radiograph of the chest is obtained. What does this film revealabout the extent of the patient's injuries, and what further investigation iswarranted?

2. Right-sided chest pain after a car accident:

The radiograph(

A

) reveals diffuse opacity throughout the righthemithorax, posterior rib fractures (

yellow arrows

), andright lateral subcutaneous gas (

white arrow

). The mediastinumis unremarkable. You order a CT scan of thechest to further evaluate these findings.Lung windows at the level of the pulmonary outflowtract (

B

) and at the level of the left ventricle (

C

) show alarge area of parenchymal opacity. Given the history oftrauma and the adjacent rib fractures, this finding is mostconsistent with lung contusion. There is also a small pleuraleffusion (

black arrows

), which likely represents hemothorax,and evidence of subcutaneous gas (

yellowarrows

), which suggests pneumothorax.The fifth, sixth, and seventh ribs are each fractured posteriorly in 2 places (some of the fracturesare not readily visible on the chest radiograph because of the overlying parenchymal lungopacity). These findings--coupled with the paradoxical motion of this portion of the chest--establishthe diagnosis of

flail segment,

which is almost always associated with contusion.The CT images also show a 5% anterior

pneumothorax

(

B and C, white arrows

), which wasnot visible on the conventional chest radiograph; it is best seen in

B.

If you suspect pneumothoraxbased on clinical findings, a tangential beam radiograph in the upright or decubitus position canhelp confirm the diagnosis. In this patient, the rib fracturesand crepitus prompted a diligent search for pneumothorax;because the decision had been made to obtaina CT scan, a tangential beam radiograph was not ordered.A chest tube was placed to manage the pneumothoraxand drain the hemothorax. The pulmonary contusionincreased in severity during the next 48 hours and resolvedwithin 72 hours of its peak.

Outcome of this case.

A follow-up upright chest radiograph(

D

) was obtained on day 4, after the chest tubewas withdrawn. The parenchymal lung opacity had diminishedsignificantly. The rib fractures were more easily seen(

arrows

), which confirmed the diagnosis of flail segment.The patient was discharged on day 6 without sequelae.